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Ultrasound imaging of the quadriceps muscle in elderly athletes and untrained men
Abstract
Ultrasound (US) technique was applied to measure the thickness, cross-sectional area (CSA), and internal structure of the quadriceps muscle in 70- to 80-year-old endurance and power athletes and untrained men. Isometric knee extension strength was higher in the power athletes than in the other groups. The mean values for thickness and CSA did not differ between the athletes and the untrained men. The intensity of the intramuscular echo was, however, lower and the echo reflected from the connective tissue septa and bone was higher in the athletes than in the untrained men. Both the CSA and internal structure of the muscle group correlated significantly with muscle strength and number of training kilometers per year. The results suggest that long-term training maintains the muscle architecture and counteracts the age-related replacement of contractile tissue by other tissues such as fat.
... These declines have been shown to have a detrimental effect on the force production capabilities of older adults [2]. Ultrasound (US) measurements of cross-sectional area (CSA) are often used to assess muscle size [3][4][5]. Evidence suggests that the CSA of most muscles in the lower limb is smaller in older compared to younger individuals [6,7]. ...
... Both of these muscles are essential for maintaining postural stability [15,16] and decelerating the limb during walking [11]. Previous studies in older adults have reported conflicting results regarding the correlations between muscle CSA of the quadriceps and physical performance outcomes, with some studies showing a significant correlation [5,8,17] and other studies demonstrating no correlation between these variables [18,19]. Such discrepancies between studies may be due in part to the dif-ferent training backgrounds of the participants that were tested. ...
... Such discrepancies between studies may be due in part to the dif-ferent training backgrounds of the participants that were tested. Also, the performance data used in these studies were limited to knee extension strength and lower-body muscle power [5,8,[17][18][19]. It remains unclear if quadriceps muscle CSA is related to other performance-based outcomes, including those from the timed up-and-go and 6-min walk tests. ...
Aims:
Normalization is a method used to account for body mass in clinical practice and research. It is unclear if this method will improve the correlation between muscle cross-sectional area (CSA) and physical performance. We examined the correlations between quadriceps muscle morphology parameters and physical performance outcomes in older women. Material and methods: Twenty older women participated in this study. Ultrasound imaging was used to measure quadriceps muscle CSA and echo intensity. Muscle CSA was expressed as an absolute value (cm2) and as a relative value normalized to body mass (cm2/kg). Physical performance was assessed from timed up-and-go and 6-min walk tests.
Results:
Relative CSA was significantly related to timed up-and-go scores (r=-0.489, p=0.029) and 6-min walking speed (r=0.606, p=0.005), whereas absolute CSA was not significantly associated with these performances (r=-0.231, p=0.327 and r=0.373, p=0.105). There was a significant correlation between absolute CSA and body mass (r=0.456, p=0.043). There were also significant correlations between echo intensity and timed up-and-go scores (r=0.556, p=0.011) and 6-min walking speed (r=-0.484, p=0.031).
Conclusions:
Our study showed that relative CSA correlated better than absolute CSA with physical performance. These findings support the need to normalize measurements of muscle CSA to body mass in older adults.
... Maximal voluntary contraction (MVC) was measured in 16 studies (Aagaard et al., 2007;Couppe et al., 2014;Korhonen et al., 2006;Korhonen et al., 2012;Marcell et al., 2014;Mikkelsen et al., 2013;Mosole et al., 2014;Pollock et al., 2015;Power et al., 2012;Power et al., 2010b;Sanada et al., 2009;Sipila and Suominen, 1991;Stenroth et al., 2016;Sundstrup et al., 2010;Suominen and Rahkila, 1991;Tarpenning et al., 2004a;Zampieri et al., 2015); 9 studies with 22 study groups were included in a meta-analysis. A meta-analysis was conducted for studies that made direct comparisons with master endurance athletes (Fig. 4); to allow for the greatest number of within-study comparisons to be incorporated into the statistical analysis. ...
... Three studies reported muscle architecture outcomes (Korhonen et al., 2006;Ojanen et al., 2007;Sipila and Suominen, 1991); included in those studies were measurements of muscle thickness (3 studies) and fascicle length (1 study). Of the studies that measured muscle thickness, one study (Korhonen et al., 2006) used the midpoint of the vastus lateralis in young controls 18-33 y (2.61 ± 0.08 cm, n = 16) and master sprinters of 60-69 (2.1 ± 0.09 cm, n = 21) and 70-84 y (1.96 ± 0.08 cm, n = 20). ...
... Another study (Ojanen et al., 2007) summed muscle thickness measurements of the vastus lateralis and vastus intermedius in master throwers of 65 (3.9 ± 0.7 cm, n = 12) and 70 (3.7 ± 0.7 cm, n = 9) years compared with older controls, 60 (3.8 ± 0.4 cm, n = 10) and 75 (3.1 ± 0.2 cm, n = 5), with no differences between the groups. The final study (Sipila and Suominen, 1991) measured muscle thickness of the rectus femoris, finding no difference between master strength/power athletes (2.73 ± 0.37 cm, n = 7), master endurance athletes (2.77 ± 0.39 cm, n = 14) and older controls (2.8 ± 0.56 cm, n = 11). One study (Korhonen et al., 2006) included measurements of vastus lateralis fascicle length which identified no significant differences between the groups of 18-33 year olds (7.91 ± 0.49 cm, n = 16), 60-69 (7.99 ± 0.27 cm, n = 21) and 70-84 (7.38 ± 0.27 cm, n = 20) year old sprint athletes. ...
Introduction:
The extent to which chronic exercise training preserves age-related decrements in physical function, muscle strength, mass and morphology is unclear. Our aim was to conduct a systematic review of the literature to determine to what extent chronically trained master athletes (strength/power and endurance) preserve levels of physical function, muscle strength, muscle mass and morphology in older age, compared with older and younger controls and young trained individuals.
Methods:
The systematic data search included Medline, EMBASE, SPORTDiscus, CINAHL and Web of Science databases.
Inclusion criteria:
i) master athletes mean exercise training duration ≥20 years ii) master athletes mean age of cohort >59 years) iii) at least one measurement of muscle mass/volume/fibre-type morphology and/or strength/physical function.
Results:
Fifty-five eligible studies were identified. Meta-analyses were carried out on maximal aerobic capacity, maximal voluntary contraction and body composition. Master endurance athletes (42.0 ± 6.6 ml kg-1 min-1) exhibited VO2max values comparable with young healthy controls (43.1 ± 6.8 ml kg-1 min-1, P = 0.84), greater than older controls (27.1 ± 4.3 ml.kg-1 min-1, P < 0.01) and master strength/power athletes (26.5 ± 2.3 ml.kg-1.min-1, P < 0.01), and lower than young endurance trained individuals (60.0 ± 5.4 ml kg-1 min-1, P < 0.01). Master strength/power athletes (0.60 (0.28 to 0.93) P < 0.01) and young controls (0.71 (0.06 to 1.36) P < 0.05) were significantly stronger compared with the other groups. Body fat % was greater in master endurance athletes than young endurance trained (-4.44% (-8.44 to -0.43) P < 0.05) but lower compared with older controls (7.11% (5.70 to 8.52) P < 0.01).
Conclusion:
Despite advancing age, this review suggests that chronic exercise training preserves physical function, muscular strength and body fat levels similar to that of young, healthy individuals in an exercise mode-specific manner.
... EI, defined as mean pixel intensity, is expressed in values from 0 (black) to 255 (white). Most studies perform the scan with the participant in the supine positon 5,6,11 and all parameters constant between subjects (including the gain) except for different predetermined depths of image acquisition. 5,6,9,10 Transverse images are obtained, some measuring just the rectus femoris and the vastus intermedius 5,11,12 and others assessing the four components of the femoral quadriceps. ...
... Most studies perform the scan with the participant in the supine positon 5,6,11 and all parameters constant between subjects (including the gain) except for different predetermined depths of image acquisition. 5,6,9,10 Transverse images are obtained, some measuring just the rectus femoris and the vastus intermedius 5,11,12 and others assessing the four components of the femoral quadriceps. 6 There is little research about the relationship between EI and physical parameters in elderly adults. ...
... 6 There is little research about the relationship between EI and physical parameters in elderly adults. Early studies found a link between femoral quadriceps EI and knee extension strength in older adults, 11,12 laying the foundation for the field of EI analysis. In this study, researchers subjectively generated EI values. ...
Objectives:
To investigate whether muscle quality based on echo intensity (EI) is associated with muscle strength (MS) and correlates with risk of frailty in elderly outpatients.
Design:
Cross-sectional, experimental study.
Setting:
Outpatient clinic.
Participants:
Individuals aged 20 to 90 (N = 112). Individuals aged 20 to 59 participated as controls. Those aged 60 and older participated in the experimental group and were subdivided into robust, prefrail, and frail according to the Fried frailty criteria.
Measurements:
EI, muscle thickness (MT), and subcutaneous fat thickness (SFT) of the anterior compartment of the thigh were measured using ultrasound images. MS was quantified using a hand dynamometer. Participants responded to a questionnaire asking about demographic and physical characteristics, frailty criteria, and quality of life.
Results:
There was a significant negative correlation between EI and MS (Women: correlation coefficient (r) = -.522, P < .001; Men: r = -.355, P < .001). A similar trend was found for MT but not SFT. Statistically significant differences were also found between EI values, MT, MS, and quality of life and the different stages of frailty (P < .01).
Conclusions:
Higher levels of EI were associated with lower levels of strength and greater frailty. These results, although needing to be replicated in larger and more-diverse populations, suggest that EI obtained using ultrasound images might be used as noninvasive imaging biomarker of frailty in elderly adults and opens the possibility of accurately testing interventions performed to prevent it.
... However, the MR system is not easily accessible and thus not suitable for large-sample assessments. With this background, QF ACSA has been assessed from the muscle strength or power of individuals [1,[12][13][14][15]. From those studies, the ability to stand up from a chair assessed by a sit-tostand (STS) test has been proposed to be one of the useful indices of skeletal muscle strength [12,[16][17][18][19][20][21]. ...
... These results supported our hypothesis that the STS test score with the upright trunk condition would be a better independent variable to estimate QF ACSA. ACSA can reflect force-generation capacity of skeletal muscles of young [13,[31][32][33]and elderly populations [13, 14, 32]. The previous studies have reported that correlation coefficients between the QF ACSA and knee extension torque in the elderly population ranged from 0.48 to 0.85 [12][13][14]. ...
... ACSA can reflect force-generation capacity of skeletal muscles of young [13,[31][32][33]and elderly populations [13, 14, 32]. The previous studies have reported that correlation coefficients between the QF ACSA and knee extension torque in the elderly population ranged from 0.48 to 0.85 [12][13][14]. The results of the present study indicated that QF ACSA was significantly correlated to knee extension torque (r = 0.70) and leg extension power (r = 0.69) (Fig. 3). ...
Background:
Although the sit-to-stand (STS) test score has been shown to relate to the strength and size of the quadriceps femoris (QF) for elderly population, it is unknown whether this relationship is influenced by a posture (i.e., the trunk being allowed to stoop or not) during the STS test. The present study investigated the relationship between STS test score and QF anatomical cross-sectional area (ACSA) in the middle-aged and elderly population with regard to the difference in the posture during STS test, and aimed to develop an accurate predicting equation of the QF ACSA from the STS test score.
Methods:
105 males (40-81 years) and 113 females (41-79 years) participated in the present study, then the subjects were divided at random as validation and cross-validation groups. Mid-thigh QF ACSA was determined by magnetic resonance imaging. Subjects performed a 10-repeated STS as fast as possible in two conditions: (1) with the trunk being allowed to stoop during the sitting phases, and (2) kept upright throughout the test. A power index of the STS test score was calculated based on an equation obtained in a previous study using the time taken for each test condition, the thigh and shank lengths, and body mass. In the validation group (n = 109), a stepwise multiple linear regression analysis was performed to create a predictive model of the ACSA with sex, age, the STS time, and power for both conditions as independent variables. The formulated predictive equation was examined in the cross-validation group (n = 109).
Results:
In the validation group, a stepwise regression analysis revealed that STS power with upright trunk condition, sex, and age but not with the stooping condition, were selected as variables to predict QF ACSA (R (2) = 0.64, P < 0.001). There was no systematic error for the relationship between predicted and measured values in the cross-validation group.
Conclusions:
These results indicate that STS test score with upright trunk condition is one of the indices of QF muscle size of the middle-aged and elderly population. The estimated predicting equation should be useful in clinical and practical settings for the health promotion.
... The ratio of QFM CSA/ total body weight was also determined. The ultrasound method and its reproducibility with in elderly women, athletes, untrained men and obese adolescents have been described in more detail elsewhere [30][31][32] . It was assumed that increased echo intensity (echogenicity i.e. higher mean grey shade value) of the muscle reflected increased tissue composition heterogeneity i.e. increased fat and connective tissue proportion 30,31 . ...
... The ultrasound method and its reproducibility with in elderly women, athletes, untrained men and obese adolescents have been described in more detail elsewhere [30][31][32] . It was assumed that increased echo intensity (echogenicity i.e. higher mean grey shade value) of the muscle reflected increased tissue composition heterogeneity i.e. increased fat and connective tissue proportion 30,31 . The results of quantitative ultrasound have been shown to correlate with values obtained from computed tomography of muscle cross sectional area and also with muscle composition measurements in elderly trained and untrained women 33 . ...
... Stegen et al. demonstrated that although the weight loss after bariatric surgery reduced dynamic and static muscle strength, they also reported that combined exercise training could prevent the decrease and even result in an increase in strength of most muscle groups 17 . Other studies in normal weight subjects have reported that long-term muscle training can maintain the muscle architecture and replace fat tissue with muscle tissue, in other words reducing the proportion of fat in the muscle tissue 30,31 . ...
Objectives:
To investigate the effects of bariatric surgery-induced weight loss on physical function, the properties of quadriceps femoris muscle (QFM), and the subjective disabilities of the subjects with excessive weight.
Methods:
Thirteen female and three male subjects were studied before and 8.8 months after Roux-en-Y gastric bypass (RYGP) operation. The health-related quality of life (RAND-36) and the self-reported disease-specific joint symptoms (WOMAC) were estimated. The objective physical function was evaluated with sock, repeated sit-to-stand, 6-minute walk, stair ascending and descending and timed up and go tests and the properties of the QFM were measured with ultrasound.
Results:
The average weight loss was 27.3 kg. Objectively measured physical function improved after RYGP operation. Physical functioning, physical role functioning and general health domain scores of the RAND-36 were significantly improved. The stiffness and function scores were lower after RYGP operation in knee OA subjects. The subcutaneous fat thickness and the absolute muscle thickness of QFM decreased, but the ratio of muscle cross sectional area/total body weight did not change. The fat and connective tissue proportion in the QFM muscle were significantly increased.
Conclusions:
The RYPG-surgery-induced weight loss exerts a positive impact on physical function but a negative impact on a muscle structure.
... In addition, aging may also affect other markers of neuromuscular function such as isometric peak torque, rate of torque development, and contractile muscle properties (e.g., electrically evoked peak twitch torque, contraction time, and half-relaxation time (Aagaard et al. 2010). Changes in muscle architecture and quality with aging include a decrease in muscle mass replaced by connective tissue (e.g., fat infiltration into the lean tissue) (Fukumoto et al. 2012;Sipila & Suominen 1993) and a reduction in pennation angle, fascicle length, and muscle thickness (Kubo et al. 2003;Narici et al. 2003). All these changes can compromise the muscle capacity to generate force (Aagaard et al. 2010). ...
... Some studies investigated master endurance athletes including different sports modalities such as cyclists, skiers, and runners, and demonstrated that chronic endurance training might preserve some aspects of neuromuscular function, muscle architecture, and muscle quality (Sipila & Suominen 1993;Tarpenning et al. 2004). However, other studies failed to demonstrate that endurance training preserved age-related neuromuscular alterations (Karamanidis & Arampatzis 2006;Marcell et al. 2014;Power et al. 2016). ...
Problem statement: Changes in the neuromuscular system owing to aging can decrease strength and muscle power. Additionally, muscle architecture and quality are affected by the natural aging process. However, it has been suggested that lifelong physical exercise may attenuate or even prevent age-related decline in physical function. Nevertheless, it is still uncertain to what extent chronic and predominantly aerobic physical training delays age-related decreases in neuromuscular function, architecture, and muscle quality. Purpose: This study was designed to compare the muscle architecture, muscle quality, and neuromuscular function of the knee extensor muscles between middle-aged runners (MR, N = 25; 53.9 ± 2.5 y, 76.5 ± 12.3 kg) and older runners (OR, N = 16; 64.4 ± 3.5 y, 70.5 ± 9.8 kg). Approach: Measures of muscle architecture were: cross-sectional area, pennation angle, fascicle length, and muscle thickness of the vastus lateralis muscle. Echo intensity of the vastus lateralis muscle was used as a marker of muscle quality, while isometric absolute and relative peak torque, rate of torque development, voluntary activation level, peak twitch torque, contraction time, and half-relaxation time of the knee extensor muscles were used as markers of neuromuscular function. Results: The OR group presented lower cross-sectional area, pennation angle, muscle thickness, absolute peak twitch torque, 100-200 ms rate of torque development, and greater echo intensity. There were no other significant differences between OR and MR groups. Conclusions: These findings suggest that though older runners have approximately 20 years of running training, they presented lower values for some markers of muscle architecture and neuromuscular function, as well as lower muscle quality compared to middle-aged runners.
... Hence, we endeavour to explore methods to accurately estimate changes in muscle volume. Previous studies have investigated the use of ultrasonography to measure muscle thickness of the QF at the anterior mid-thigh as an indicator of muscle size (Sipila & Suominen, 1991 Abe et al., 1997 ). However, there is no consensus that the anterior mid-thigh is the best representative region for measuring muscle thickness of the QF. ...
... Several studies have reported the change in muscle size of the QF (e.g. atrophy or hypertrophy) based on changes in muscle thickness using ultrasonography (Sipila & Suominen, 1991 Abe et al., 1997 Abe et al., , 2000 Reid et al., 2004). Muscle thickness at the anterior mid-thigh has been frequently used to estimate muscle size. ...
The present study aimed to determine relationships between intramyocellular lipid and biochemical profiles or muscle strength in elderly (n = 15; mean age, 71 years) and young (n = 15; mean age, 21 years) male and female adults. Levels of intramyocellular lipid in the vastus lateralis and biceps femoris muscles were determined using (1) H-magnetic resonance spectroscopy. Fasting blood samples were collected to measure levels of glucose, insulin, haemoglobin A1c, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, free fatty acid, triglyceride, adiponectin, and high-sensitivity C-reactive protein. Muscle strength was assessed as maximal voluntary contraction during isometric knee extension. Muscle cross-sectional area in the vastus lateralis was measured using magnetic resonance imaging. Specific force (N cm(-2) ) indicating force generation capacity was calculated as muscle strength (N) divided by the muscle cross-sectional area of the vastus lateralis (cm(2) ). The intramyocellular lipid content was similar in both muscles in both groups. The intramyocellular lipid content in the biceps femoris significantly correlated with serum free fatty acid levels (r = 0·62, P<0·05), and that in the vastus lateralis significantly and inversely correlated with specific force (r = -0·58, P<0·05) in the young, but not in the elderly adults. The relationship between the intramyocellular lipid content in the thigh muscles and biochemical profiles, or specific force differed between elderly and young adults. Age-associated changes in morphology, function and metabolic factors apparently influence intramyocellular lipid metabolism in the thigh muscles.
© 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.
... In vivo biomedical imaging methodologies, such as ultrasonography [5][6][7], magnetic resonance imaging (MRI) [8][9][10][11][12][13][14][15] or X-ray computed tomography (CT) [16][17][18], have been applied to muscle imaging. Ultrasonography is in both routine clinical use (for human patients) [6] and preclinical use (for animal models) [7] because of its lower cost, shorter acquisition time and avoidance of ionizing radiation. ...
... In vivo biomedical imaging methodologies, such as ultrasonography [5][6][7], magnetic resonance imaging (MRI) [8][9][10][11][12][13][14][15] or X-ray computed tomography (CT) [16][17][18], have been applied to muscle imaging. Ultrasonography is in both routine clinical use (for human patients) [6] and preclinical use (for animal models) [7] because of its lower cost, shorter acquisition time and avoidance of ionizing radiation. The imaging resolution, however, limits ultrasonography in resolving individual myofibers, which are typically 30 to 50 µm in diameter [4]. ...
We have developed an extremely miniaturized optical coherence tomography (OCT) needle probe (outer diameter 310 µm) with high sensitivity (108 dB) to enable minimally invasive imaging of cellular structure deep within skeletal muscle. Three-dimensional volumetric images were acquired from ex vivo mouse tissue, examining both healthy and pathological dystrophic muscle. Individual myofibers were visualized as striations in the images. Degradation of cellular structure in necrotic regions was seen as a loss of these striations. Tendon and connective tissue were also visualized. The observed structures were validated against co-registered hematoxylin and eosin (H&E) histology sections. These images of internal cellular structure of skeletal muscle acquired with an OCT needle probe demonstrate the potential of this technique to visualize structure at the microscopic level deep in biological tissue in situ.
... Previous studies have investigated the use of ultrasonography to measure muscle thickness of the QF at the anterior mid-thigh as an indicator of muscle size (Sipila & Suominen, 1991Abe et al., 1997). However, there is no consensus that the anterior mid-thigh is the best representative region for measuring muscle thickness of the QF. ...
... Several studies have reported the change in muscle size of the QF (e.g. atrophy or hypertrophy) based on changes in muscle thickness using ultrasonography (Sipila & Suominen, 1991Abe et al., 1997Abe et al., , 2000Reid et al., 2004). Muscle thickness at the anterior mid-thigh has been frequently used to estimate muscle size. ...
The purpose of this study was to establish an accurate estimation of muscle atrophy in the quadriceps femoris (QF) muscle group. Eighteen individuals who underwent meniscectomy participated in the study (nine men and nine women, mean age 44·4 years). Both operated and non-operated thighs were scanned by magnetic resonance imaging to determine the volume and thickness of the QF muscle group. Muscle volume was estimated using eleven axial images, and muscle thickness was measured at the anterior, lateral and medial regions of the proximal, mid- and distal thigh, respectively. A stepwise linear regression analysis was performed to obtain the relationship between the difference in muscle volume and the difference in muscle thickness between operated and non-operated limbs. There was no significant difference in muscle volume of the QF between operated (806·6 ± 220·0 cm(3) ) and non-operated (913·7 ± 241·5 cm(3) ) limbs. Based on the stepwise linear regression analysis, the difference in muscle volume was significantly correlated with the difference in muscle thickness at the anterior proximal thigh and lateral mid-thigh and anterior mid-thigh (R = 0·93, P<0·01). In conclusion, the difference in muscle volume between operated and non-operated limbs can be estimated accurately by measuring muscle thickness of the QF at three sites: the anterior proximal thigh, the lateral mid-thigh and anterior mid-thigh. Muscle thickness can be measured easily using imaging techniques such as ultrasonography. We propose that this method provides an easy and accurate estimate of knee surgery-induced muscle atrophy in clinical medicine.
... There have been a large number of reports of a loss of skeletal muscle mass and force generation capacity as a result of the aging process (Aniansson et al. 1980(Aniansson et al. , 1983Grimby et al. 1984;Faulkner 1988, 1991;Edstrom and Larsson 1987;Jubrias et al. 1997;Lexell et al. 1983Lexell et al. , 1988Sipilä and Suominen 1991;Lamboley et al. 2015). However, it is not yet clear to what extent this reduction in force is due to an intrinsic loss of force generating capacity of the contractile proteins in a particular type of fibre, to the change in the fibre type composition, or to a reduction of the crosssectional area of the muscle. ...
The single freshly skinned muscle fibre technique was used to investigate Ca ²⁺ - and Sr ²⁺ -activation properties of skeletal muscle fibres from elderly women (66–90 years). Muscle biopsies were obtained from the vastus lateralis muscle. Three populations of muscle fibres were identified according to their specific Sr ²⁺ -activation properties: slow-twitch (type I), fast-twitch (type II) and hybrid (type I/II) fibres. All three fibre types were sampled from the biopsies of 66 to 72 years old women, but the muscle biopsies of women older than 80 years yielded only slow-twitch (type I) fibres. The proportion of hybrid fibres in the vastus lateralis muscle of women of circa 70 years of age (24%) was several-fold greater than in the same muscle of adults (< 10%), suggesting that muscle remodelling occurs around this age. There were no differences between the Ca ²⁺ - and Sr ²⁺ -activation properties of slow-twitch fibres from the two groups of elderly women, but there were differences compared with muscle fibres from young adults with respect to sensitivity to Ca ²⁺ , steepness of the activation curves, and characteristics of the fibre-type dependent phenomenon of spontaneous oscillatory contractions (SPOC) (or force oscillations) occurring at submaximal levels of activation. The maximal Ca ²⁺ activated specific force from all the fibres collected from the seven old women use in the present study was significantly lower by 20% than in the same muscle of adults. Taken together these results show there are qualitative and quantitative changes in the activation properties of the contractile apparatus of muscle fibres from the vastus lateralis muscle of women with advancing age, and that these changes need to be considered when explaining observed changes in women’s mobility with aging.
... There have been a large number of reports of a loss of skeletal muscle mass and force generation capacity as a result of the aging process (Aniansson et al., 1980;Aniansson et al., 1983;Grimby et al., 1984;Faulkner, 1988, 1991;Edstrom and Larsson, 1987;Jubrias et al., 1997;Lexell et al., 1983;Lexell et al., 1988;Sipilä andSuominen, 1991 Lamboley et al. 2015). However, it is not yet clear to what extent this reduction in force is due to an intrinsic loss of force generating capacity of the contractile proteins in a particular type of bre, to the change in the bre type composition, or to a reduction of the cross-sectional area of the muscle. ...
The single skinned muscle fibre technique was used to investigate Ca ²⁺ -and Sr ²⁺ -activation properties of skeletal muscle fibres from elderly women (66-90 years). Muscle biopsies were obtained from the vastus lateralis muscle. Three populations of muscle fibres were identified according to their specific Sr ²⁺ -activation properties: slow-twitch (type I), fast-twitch (type II) and hybrid (type I/II) fibres. All three fibre types were sampled from the biopsies of 66 to 72 years old women, but the muscle biopsies of women older than 80 years yielded only slow-twitch (type I) fibres. The proportion of hybrid fibres in the vastus lateralis muscle of women of circa 70 years of age (24%) was several-fold greater than in the same muscle of adults (<10%), suggesting that muscle remodelling occurs around this age. There were no differences between the Ca ²⁺ -and Sr ²⁺ -activation properties of slow-twitch fibres from the two groups of elderly women, but there were differences compared with muscle fibres from adults with respect to sensitivity to Ca ²⁺ , steepness of the activation curves, and characteristics of the fibre-type dependent phenomenon of spontaneous force oscillations occurring at submaximal levels of activation. The maximal Ca ²⁺ activated specific force from all the fibres collected from the seven old women use in the present study was significantly lower by 20% than in the same muscle of adults. Taken together these results show there are qualitative and quantitative changes in the activation properties of the contractile apparatus of muscle fibres from the vastus lateralis muscle of women with advancing age, and that these changes need to be considered when explaining observed changes in women’s mobility with aging.
... Sarcopenic muscles have more connective tissue compared to muscles in non-sarcopenic individuals, 43 and may present as grade 3A on the SEM. Muscle ultrasound in elderly athletes and untrained men has shown that echo intensity is higher in untrained men, 44 corresponding to age-related replacement of contractile tissue by other tissues, such as fat. In contrast, in severe sarcopenia and cachexia, 45 the muscle echo intensity will be even higher, presenting as grade 4A on the SEM. ...
The assessment of soft tissue stiffness is important to evaluate many neuromusculoskeletal conditions. Several tools have been proposed for the assessment of stiffness, but ultrasonography appears to be most practical. The reflection of ultrasound waves as it travels through tissue enables assessment of tissue echogenicity, which is influenced by the characteristics of the sound wave as well as the characteristics of the tissue through which it passes, such as the amount of fat and fibrous tissue. However, tissue stiffness is not directly proportional to its echogenicity. Hence evaluation of echogenicity, as a stand-alone technique, is inadequate to describe its mechanical properties. The aim of this manuscript is to present a method of combining echogenicity evaluation by ultrasound and stiffness evaluation by palpation to better describe the mechanical properties of muscle using a stiffness-echogenicity matrix.
... A recent meta-analysis highlighted research gaps due to most studies having low participant numbers with very few female athletes, limited outcome assessments and unclear demographics (Mckendry et al., 2018). For example, two studies ( Power et al., 2012;Stenroth et al., 2016) showed higher maximal force or power in Masters endurance runners compared with non-athletic old, but several others showed no difference between Masters endurance runners and controls (Aagaard et al., 2007;Michaelis et al., 2008;Mikkelsen et al., 2013;Couppe et al., 2014;Piasecki et al., 2016; or even lower (Sipilä and Suominen, 1991;Sanada et al., 2009) maximal force or power in Masters endurance runners compared with non-athletic old. More recently, Fien et al. (2017) reported high levels of physical function, low body fat, and good health status of Masters athletes, but these characteristics declined with advancing age and because no comparison was made with non-athletic old it is not possible to know if these characteristics were any better than typical healthy old. ...
Masters endurance runners can epitomize healthy aging; being reflective of the physiological processes of aging without the compounded effects of inactivity. The primary aim of the present study was to determine, using cross-sectional data, whether individuals taking up training after the age of 50 years can achieve the same level of athletic performance and musculoskeletal characteristics in their older age as those who trained all of their adult lives. A total of 150 master endurance runners [age 68 (5) years; 111 male, 39 female] were divided into early starters (training all of their adulthood) and late starters (started training after age 50 years). A comparative non-athletic group of 59 healthy older adults [age 73 (4) years; 30 female, 29 male] were additionally included for analysis. Training intensity, age-graded performance (AGP) and musculoskeletal assessments were performed. Results showed that there was no difference between athlete groups for training intensity or age-graded performance, despite the 30-year difference in training history. Body fat percentage and leg lean mass did not differ between athlete groups, but were 17% lower and 12% greater, respectively, in athlete groups compared with controls. Power normalized to body mass did not differ between any groups. Spine BMD was lower in late starters than controls, while early starters did not differ from late starters or controls. Hip BMD did not differ between any of the groups. These findings show that the Masters athletes we studied that started intense endurance running after the age of 50 years had lower body fat and higher leg lean mass compared to non-athletes. Body composition and athletic performance of the late starters was very similar to those who trained all of their adult lives.
... The patient was in the supine position, the probe was placed longitudinally on the thigh, and minimal pressure was applied. [18][19][20] The scan was performed shortly after admission to (day 2-4) and again at discharge from (day 5-13) the hospital. For each patient 3 images were obtained at each timepoint. ...
Background and Purpose
Hospital admission for older patients has been linked to loss of muscle mass and function, and the former can be measured with ultrasonography during hospitalization.
Methods
Two studies were carried out. In Study 1 69 patients’ (85±8 yrs.) activity level was measured with ActivPal and quadriceps thickness measured twice with ultrasonography during hospitalization. In Study 2 10 older patients (85±8 yrs.) and 10 healthy young subjects (23±2 yrs.) had their quadriceps thickness measured on 2 consecutive days with ultrasonography that included a pressure calibrator.
Results
In study 1 the results revealed that the older patients had a reduction in thigh muscle thickness together with very low levels of activity level during hospitalization. Patients with a <95% inactivity level show a 1.8% reduction in muscle thickness, and those with a >95% inactivity level had a 7.0% reduction. In study 2 ultrasonographic measurements were performed using a pressure calibrator, and these results yielded very good reproducibility. Typical error was 1.7% for the young and 7.2% for the old persons. This high reproducibility and low error improve the ability to detect significant changes over time.
Conclusion
Improving the ultrasonography method including use of a pressure calibrator can result in greater reproducibility.
This article is protected by copyright. All rights reserved.
... This modality enables investigation of a large muscle portion and of different muscles, but the acquisition process is complicated, requiring the use of guides, a high level of experience on the part of the operator, high precision in manual tracing, dedicated software tools and time. On the other hand, analysis of both muscle size and structure can also be effectively performed by extracting the visible muscle CSA from conventional transverse US scans (Hammond et al. 2014;Seymour et al. 2009;Sipila and Suominen 1991). This CSA quantification has proven to be useful in assessing muscle size and its changes relative to musculoskeletal training and rehabilitation (Damas et al. 2016;Rieder et al. 2015;Seymore et al. 2017) as well as to neuromuscular disorders (Pillen et al. 2008). ...
Ultrasonography allows non-invasive and real time-measurement of the visible cross-sectional area (CSA) of muscles, which is a clinically relevant descriptor of muscle size. The aim of this study was to develop and validate a fully automatic method called transverse muscle ultrasound analysis (TRAMA) for segmentation of the muscle in B-mode transverse ultrasound images and measurement of muscle CSA. TRAMA was tested on a database of 200 ultrasound images of the rectus femoris, vastus lateralis, tibialis anterior and medial gastrocnemius muscles. The automatic CSA measurements were compared with manual measurements obtained by two operators. There were no statistical differences between the automatic and manual measurements of CSA of the four muscles, and TRAMA performance was comparable to intra-operator variability in terms of the Dice similarity coefficient and Hausdorff distance between the automatic and manual segmentations. Compared with manual segmentation, the Dice similarity coefficient for the proposed method was always higher than 93%; the Hausdorff distance never exceeded 4 mm, and the maximum absolute error was 62 mm². TRAMA is the first automated algorithm that analyzes and segments ultrasound scans of the muscle in the transverse plane. It can be adopted in future studies for automatic segmentation of muscle regions of interest to enhance and automatize a multitexture analysis of muscle structure.
... The QMT measurement is a valid method of assessing muscle wasting and physical function in patients with sub-acute stroke during hospitalization for convalescent rehabilitation [13], and the QMT measurement also correlates with leg muscle mass in healthy volunteers, athletes, and elderly persons [18,19]; therefore, we measured QMT instead of the lower leg muscle mass. QMT was measured as the total value of the thickness of the rectus femoris and vastus intermedius muscles directly by a single examiner using a frozen B-mode ultrasound imaging system (LOGIQ P5; GE Healthcare Japan, Tokyo, Japan) and an 8-MHz transducer. ...
Increasing physical activity (PA) is an important rehabilitation target for patients with sub-acute stroke during hospitalization in order to recover physical function and prevent stroke recurrence. However, the characteristics of low PA in stroke patients during hospitalization who were targets for increased intervention have not been reported. The purpose of this study was to investigate the relationship between the daily number of steps and physical function and quadriceps muscle thickness (QMT) in patients with sub-acute stroke during hospitalization for convalescence rehabilitation. Twenty-nine patients with ischemic or haemorrhagic stroke (mean age, 69 ± 11 years) hospitalized for inpatient convalescent rehabilitation were included. PA was measured using a three-dimensional accelerometer that calculates the daily number of steps taken. Physical function was measured by a short physical performance battery (SPPB; 0-12 points) and the leg motor selectivity score (6 motor stages defined by Brunnstrom), and the QMT of both legs was measured using ultrasonography. PA was significantly correlated with the SPPB score (r = 0.63, p = 0.0002), QMT on the paretic side (r = 0.41, p = 0.02), and QMT on non-paretic side (r = 0.56, p = 0.002). There were no significant effects of the leg motor selectivity score on daily PA (F = 1.37, p = 0.27). In the multiple regression analysis, only the SPPB score showed significant linear regression (β = 0.44, p = 0.02). PA in male patients with sub-acute stroke during hospitalization was related to physical function and QMT and not with the severity of paresis.
... 34,[37][38][39][40] Other studies have compared ultrasound MT measurement to muscle mass/volume assessed by either DXA or MRI. 6,11,13,14,16,41 However, to the best of the authors' knowledge, the present study is the first to investigate RT-induced changes in MT and ACSA or VOL, respectively, assessed by ultrasound and MRI. ...
Aim:
Muscle thickness (MT) measured by ultrasound has been used to estimate cross-sectional area (measured by CT and MRI) at a single time-point. We tested whether MT could be used as a valid marker of MRI determined muscle anatomical cross-sectional area (ACSA) and volume changes following resistance training (RT).
Methods:
Nine healthy, young, male volunteers (24±2 y.o., BMI 24.1±2.8 kg/m(2) ) had vastus lateralis (VL) muscle volume (VOL) and ACSA mid (at 50% of femur length, FL) assessed by MRI, and VL MT measured by ultrasound at 50% FL. Measurements were taken at baseline and after 12 weeks of isokinetic RT. Differences between baseline and post-training were assessed by Student's paired t-test. The relationships between MRI and ultrasound measurements were tested by Pearson's correlation.
Results:
After RT, MT increased by 7.5±6.1% (p<0.001), ACSAmid by 5.2±5% (p<0.001) and VOL by 5.0±6.9% (p<0.05) (values: means±S.D.). Positive correlations were found, at baseline and 12 weeks, between MT and ACSAmid (r=0.82, p<0.001 and r=0.73, p<0.001, respectively), and between MT and VOL (r=0.76, p < 0.001 and r=0.73, p < 0.001, respectively). The % change in MT with training was correlated with % change in ACSAmid (r=0.69, p = 0.01), but not % change in VOL (r= 0.33, p>0.05).
Conclusions:
These data support evidence that MT is a reliable index of muscle ACSAmid and VOL at a single time-point. MT changes following RT are associated with parallel changes in muscle ACSAmid but not with the changes in VOL, highlighting the impact of RT on regional hypertrophy. This article is protected by copyright. All rights reserved.
... These latter techniques are considered the gold standard for muscle cross-sectional area, therefore using DXA to assess muscle hypertrophy was considered appropriate. The muscle thickness assessed via ultrasound has also been closely correlated with muscle cross-sectional area measured from CT and MRI (2,34). An advantage of the ultrasound compared with DXA is its ability to make a distinction between individual muscles within a region of the body such as the triceps and biceps for the upper arms. ...
German Volume Training (GVT), or the 10 sets method, has been used for decades by weightlifters to increase muscle mass. To date, no study has directly examined the training adaptations following GVT. The purpose of this study was to investigate the effect of a modified GVT intervention on muscular hypertrophy and strength. Nineteen healthy males were randomly assign to 6 weeks of 10 or 5 sets of 10 repetitions for specific compound resistance exercises included in a split-routine performed 3 times per week. . Total and regional lean body mass, muscle thickness, and muscle strength were measured before and after the training program. Across groups, there were significant increases in lean body mass measures, however greater increases in trunk (p = 0.043; ES = -0.21) and arm (p = 0.083; ES = -0.25) lean body mass favored the 5-SET group. No significant increases were found for leg lean body mass or measures of muscle thickness across groups. Significant increases were found across groups for muscular strength, with greater increases in the 5-SET group for bench press (p = 0.014; ES = -0.43) and lat pull-down (p = 0.003; ES = -0.54). It seems that the modified GVT program is no more effective than performing 5 sets per exercise for increasing muscle hypertrophy and strength. To maximize hypertrophic training effects it is recommended that 4-6 sets per exercise be performed, as it appears gains will plateau beyond this set range and may even regress due to overtraining.
... The usefulness of new UI analysis techniques has been demonstrated in various studies on animals and humans [20]. For example, these techniques have helped to quantify changes in the composition of an exercised muscle compared to an unexercised muscle in an elderly population [21][22][23]. These techniques have also revealed differences in the histological composition of the supraspinatus muscle and the quadriceps muscle in adults [24] and have been successfully used to detect structural changes in four key muscles in youths with neuromuscular disorders [25]. ...
Background
Quantifying the integrity of the Achilles tendon (AT) is a rehabilitation challenge. Adopting quantitative ultrasound measurements (QUS measurements) of the AT could fill this gap by 1) evaluating the test-retest reliability and accuracy of QUS measurements of the AT; 2) determining the best protocol for collecting QUS measurements in clinical practice. MethodsA total of 23 ATs with symptoms of Achilles tendinopathy and 63 asymptomatic ATs were evaluated. Eight images were recorded for each AT (2 visits × 2 evaluators × 2 images). Multiple sets of QUS measurements were taken: geometric (thickness, width, area), first-order statistics (computed from a grayscale histogram distribution: echogenicity, variance, skewness, kurtosis, entropy) and texture features (computed from co-occurrence matrices: contrast, energy, homogeneity). A generalizability study quantified the reliability and standard error of measurement (accuracy) of each QUS measurement, and a decision study identified the best measurement taking protocols. ResultsGeometric QUS measurements demonstrated excellent accuracy and reliability. QUS measurements computed from the grayscale histogram distribution revealed poor accuracy and reliability. QUS measurements derived from co-occurrence matrices showed variable accuracy and moderate to excellent reliability. In clinical practice, using an average of the results of three images collected by a single evaluator during a single visit is recommended. Conclusions
The use of geometric QUS measurements enables quantification of AT integrity in clinical practice and research settings. More studies on QUS measurements derived from co-occurrence matrices are warranted.
... This technique is generally known to be reliable for stroke patients, 22 and a correlation with leg muscle mass in healthy volunteers, athletes, and elderly persons has been shown. 33,34 Moreover, a relationship between muscle thickness and muscle strength has also been reported, 35 but it has not been studied in acute stroke subjects. In the present study, it could not be shown that the decreases in quadriceps muscle thickness in acute stroke patients were associated with changes in meaningful functional parameters. ...
Background: Loss of skeletal muscle mass is one of the main reasons for disability in patients with stroke. However, lower leg muscle wasting has not been studied in acute stroke patients. Objective: To investigate the changes in quadriceps muscle thickness in acute non-Ambulatory stroke survivors. Methods: A total of 16 consecutive acute non-Ambulatory stroke survivors who were in acute inpatient rehabilitation, with a mean age of 72.1 years, were included in the study. Quadriceps muscle thickness was examined in their paretic and non-paretic limbs within the first week from admission (first week), 1 week after the first examination (second week), and 1 week after the second week examination (third week) using ultrasonography. Results: Quadriceps muscle thickness in the paretic limb decreased every week (mean% difference between the first and second weeks, 12.8, 95% confidence interval (CI) 5.3-20.2%; mean% difference between the second and third weeks, 10.1, 95% CI 5.2-14.9%). Quadriceps muscle thickness in the non-paretic limb was lower in the second and third weeks than the first week, but there was no difference between the second and third weeks (mean% difference between the first and second weeks, 9.3, 95% CI 2.5-16.1%; mean% difference between the second and third weeks, 5.3, 95% CI {1.6 to 12.1%). Conclusion: Quadriceps muscle thickness decreased in acute non-Ambulatory stroke survivors not only in the paretic limb but also in the non-paretic limb, particularly during the period from admission to the second week.
... If researchers or doctors cannot access an MRI, US is a substitutable methodology to estimate IntraMAT based on echo intensity [13,20]. In earlier studies, Sipilä and Suominen [21,22] showed that echo intensity of the quadriceps femoris is lower in elderly athletes than untrained individuals, suggesting that elderly athletes have less IntraMAT content than healthy sedentary individuals. As with MRI, however, it is not clear that the origin of reflected echo of skeletal muscle sonography comes from in the muscle cells. ...
... The practical consequence of this error is that the diagnosis of muscle that is affecting a particular activity may be wrong. Furthermore, since older individuals present significant alterations in their muscle architecture, which leads them to produce less muscle force, it is natural to infer that generic models with a muscle architecture based in young adults may not be accurate (Narici, Maganaris, Reeves, & Capodaglio, 2003; Narici, Reeves, Morse, & Maganaris, 2004; Sipila & Suominen, 1991). The use of muscle architecture specifically from older individuals would be beneficial to the estimation. ...
The aim of this study was to compare the knee extension moment of older individuals with the muscle moment estimated through a biomechanical model. This was accomplished by using (1) the specific muscle architecture data of individuals, and (2) the generic muscle architecture available in the literature. The muscle force estimate was determined using a model with the muscle architecture from cadavers and the individual vastus lateralis muscle architecture of sixteen older volunteers. For the muscle moment comparison, all of the volunteers performed maximal voluntary isometric contractions (MVIC) in five different knee extension position angles. The architectural data was acquired using both resonance and ultrasound imaging. Both estimated muscle moments (generic and individual) were higher than the experimental. The architecture of the other vastii may be necessary to make the model more accurate for the older population. Although other factors inherent to ageing, such as co-contractions, fiber type percentage, and passive forces are not considered in the model, they could be responsible for the differences between moments in older people.
... Similarly, research in Division I football players [15] and female soccer players [12] found no differences in baseline VL CSA or EI between starters and non-starters. It is possible that homogenous samples engaged in the same training program may have similar EI despite differences in body composition, as research has suggested that training may influence EI values [12,25]. In contrast with previous research [15,19], the current study did not find a significant correlation between VL CSA and leg LBM; the small sample tested may have contributed to this discordant finding. ...
Research has demonstrated an elevated prevalence of body weight concerns and scoliosis among female gymnasts. The purpose of the current pilot study was to evaluate the utility of ultrasonography and dual-energy X-ray absorptiometry (DXA) as practical imaging modalities to measure body composition and spinal curvature variables that may correlate with performance in female collegiate gymnasts (n=15). DXA was used to evaluate body composition and lateral spinal curvature, utilizing a modified Ferguson method. Echo intensity (EI) and cross-sectional area (CSA) of the vastus lateralis were determined from a panoramic cross-sectional ultrasound image. For returning athletes (n=9), performance scores from the previous season were averaged to quantify performance. The average performance score was correlated with lean mass of the arms (R=0.714; P=0.03) and right leg (R=0.680; P=0.04). Performance was not correlated with total mass, fat mass or body fat percentage (P>0.10). Scoliosis was identified in 3 of 15 scans (20%). Echo intensity and CSA of the vastus lateralis were inversely correlated with each other (R=-0.637, P=0.01), but not with other measures of body composition or performance. Results suggest that limb LBM may be a determinant of gymnastics performance, and DXA may provide important health and performance-related information for female collegiate gymnasts.
© Georg Thieme Verlag KG Stuttgart · New York.
... In addition to reduced muscle size, previous research suggests that a reduction in muscle quality is also apparent in hallux valgus, evident by the frequent occurrence of lipid-laden fibres within the muscle [11]. Increased deposition of intra-muscular adipose tissue may be a result of reduced muscle activity [12], but is also recognised as an age-related change [13]. In our previous sonographic study we observed an increase in echointensity within several of our images [8]. ...
... Finska forskare har i en serie undersökningar [18][19][20] utvärderat muskelstruktur och muskelfunktion hos äldre inaktiva män och kvinnor respektive äldre individer som motionerat under stora delar av sitt liv. Uthållighets-och styrketränande äldre personer jämför-des med friska äldre kontroller, och muskelstyrkan mättes objektivt, parallellt med att muskelvolym och muskelsammansättning utvärderades med ultraljud och datortomografi. ...
A well-known effect of increasing age is the gradual reduction of muscle function, and thus of performance in the activities of daily living. Recent research has shown that, even among the very elderly, exercise can improve not only strength and endurance, but also balance and mobility, thus reducing the risk of falls. The possibility of counteracting some of the age-related muscle changes has also been demonstrated. The article reviews current knowledge of strength and endurance training in the elderly, the importance of exercise to improve physical performance, and how lifelong exercise can counteract the effects associated with the ageing of the neuromuscular system.
... This technique is generally known to be reliable for stroke patients, 22 and a correlation with leg muscle mass in healthy volunteers, athletes, and elderly persons has been shown. 33,34 Moreover, a relationship between muscle thickness and muscle strength has also been reported, 35 but it has not been studied in acute stroke subjects. In the present study, it could not be shown that the decreases in quadriceps muscle thickness in acute stroke patients were associated with changes in meaningful functional parameters. ...
Loss of skeletal muscle mass is one of the main reasons for disability in patients with stroke. However, lower leg muscle wasting has not been studied in acute stroke patients.
To investigate the changes in quadriceps muscle thickness in acute non-ambulatory stroke survivors.
A total of 16 consecutive acute non-ambulatory stroke survivors who were in acute inpatient rehabilitation, with a mean age of 72.1 years, were included in the study. Quadriceps muscle thickness was examined in their paretic and non-paretic limbs within the first week from admission (first week), 1 week after the first examination (second week), and 1 week after the second week examination (third week) using ultrasonography.
Quadriceps muscle thickness in the paretic limb decreased every week (mean% difference between the first and second weeks, 12.8, 95% confidence interval (CI) 5.3-20.2%; mean% difference between the second and third weeks, 10.1, 95% CI 5.2-14.9%). Quadriceps muscle thickness in the non-paretic limb was lower in the second and third weeks than the first week, but there was no difference between the second and third weeks (mean% difference between the first and second weeks, 9.3, 95% CI 2.5-16.1%; mean% difference between the second and third weeks, 5.3, 95% CI - 1.6 to 12.1%).
Quadriceps muscle thickness decreased in acute non-ambulatory stroke survivors not only in the paretic limb but also in the non-paretic limb, particularly during the period from admission to the second week.
... In addition to reduced muscle size, previous research suggests that a reduction in muscle quality is also apparent in hallux valgus, evident by the frequent occurrence of lipid-laden fibres within the muscle [11]. Increased deposition of intra-muscular adipose tissue may be a result of reduced muscle activity [12], but is also recognised as an age-related change [13]. In our previous sonographic study we observed an increase in echointensity within several of our images [8]. ...
The abductor hallucis muscle plays an important role in maintaining alignment of the first metatarsophalangeal joint. The aims of this study were (1) to determine differences in abductor hallucis muscle characteristics in people with hallux valgus between three age groups (20-44 years, 45-64 years, and 65+ years); and (2) to determine the association between age and abductor hallucis size and quality.
Characteristics of the abductor hallucis muscle were measured in 96 feet with hallux valgus using musculoskeletal ultrasound. Muscle characteristics included width, thickness, cross-sectional area and echo-intensity. A one-way ANCOVA was conducted to compare the mean muscle characteristic values between the three age groups while adjusting for hallux valgus severity as a covariate. A Bonferroni post-hoc was used to adjust for multiple testing (p < 0.0167). Spearman's rho correlation coefficient was used to determine the association between age and the abductor hallucis muscle parameters.
There was a significant difference in dorso-plantar thickness (p = 0.003) and cross-sectional area (p = 0.008) between the three age groups. The Bonferroni post hoc analysis revealed a significant difference in mean thickness and mean cross-sectional area between the 20-44 age group (p = 0.003) and the 65+ age group (p = 0.006). No significant differences were noted between the three age groups for medio-lateral width (p > 0.05) or echo-intensity (p > 0.05). Increasing age was significantly associated with a reduction in dorso-plantar thickness (r = -0.27, p = 0.008) and cross-sectional area (r = -0.24, p = 0.019) but with small effect sizes. There was no significant correlation between age and medio-lateral width (r = -0.51, p = 0.142) or echo intensity (r =0.138, p =0.179).
Increasing age is associated with a greater reduction in size of the abductor hallucis muscle in people with hallux valgus. People over the age of 65 years old with hallux valgus display a significant reduction in abductor hallucis muscle size compared to those aged less than 45 years old. This is consistent with age-related changes to skeletal muscle.
... The reduced physical activity may at least partly contribute to the loss of muscle strength in older age (Rantanen et al. 1997b, Rantanen et al. 1999b, Hunter et al. 2000, Hughes et al. 2001). Many studies with mainly cross-sectional design have shown that muscle strength is lower among people with lower levels of physical activity (sedentary) than among the more physically active people (Sipilä et al. 1991, Rantanen et al. 1997b, Hunter et al. 2000. The effects of decreases in physical activity and muscle strength are mutually reinforcing (Rantanen et al. 1999b). ...
... The readings were taken at mid-thigh level bilaterally 16,42,45 the isometric strength and ultrasonographic measurements of width of Quadriceps femoris muscle bilaterally were obtained for each subject at baseline and at the end of six weeks. The sequence of testing for the outcome measures was randomized among participants. ...
... While the former observed relationships are consistent with the literature (Cormie et al., 2011;Häkkinen and Keskinen, 1989;Häkkinen et al., 1996), the latter observations appear to be contradictory. However, they may also be the result of physical activity and/or limb preference (Sipila and Suominen, 1991;Kearns et al., 2001). Both contractile (i.e. ...
Muscle architecture is a determinant for sprinting speed and jumping power, which may be related to anaerobic sports performance. In the present investigation, the relationships between peak (PVJP) and mean (MVJP) vertical jump power, 30m maximal sprinting speed (30M), and muscle architecture were examined in 28 college-aged, recreationally-active men (n = 14; 24.3 ± 2.2y; 89.1 ± 9.3kg; 1.80 ± 0.07 m) and women (n = 14; 21.5 ± 1.7y; 65.2 ± 12.4kg; 1.63 ± 0.08 m). Ultrasound measures of muscle thickness (MT), pennation angle (PNG), cross-sectional area (CSA), and echo intensity (ECHO) were collected from the rectus femoris (RF) and vastus lateralis (VL) of both legs; fascicle length (FL) was estimated from MT and PNG. Men possessed lower ECHO, greater muscle size (MT & CSA), were faster, and were more powerful (PVJP & MVJP) than women. Stepwise regression indicated that muscle size and quality influenced speed and power in men. In women, vastus lateralis asymmetry negatively affected PVJP (MT: r = -0.73; FL: r = -0.60) and MVJP (MT: r = -0.76; FL: r = -0.64), while asymmetrical ECHO (VL) and FL (RF) positively influenced MVJP (r = 0.55) and 30M (r = 0.57), respectively. Thigh muscle architecture appears to influence jumping power and sprinting speed, though the effect may vary by gender in recreationally-active adults. Appropriate assessment of these ultrasound variables in men and women prior to training may provide a more specific exercise prescription. Key pointsThe manner in which thigh muscle architecture affects jumping power and sprinting speed varies by gender.In men, performance is influenced by the magnitude of muscle size and architecture.In women, asymmetrical muscle size and architectural asymmetry significantly influence performance.To develop effective and precise exercise prescription for the improvement of jumping power and/or sprinting speed, muscle architecture assessment prior to the onset of a training program is advised.
... Another method, ultrasound imaging, has been suggested to provide quantitative information about the functional capacity of muscles (Sipilä and Suominen, 1991) as found when measuring the cross-sectional area and thickness of the quadriceps muscle. Kiliaridis and Kälebo (1991) applied the ultrasonography method on the masseter muscle, using it to measure muscle thickness, and showed that this method is both reliable and accurate. ...
... However, such measurements require expensive equipment and specific expertise to interpret the images, and in the first case involve the exposure of the subjects to ionizing radiation (Menon et al., 2012). Ultrasound apparatus, on the other hand, is an easily available, portable, valid, safe and reliable alternative to CT and MG for measuring superficial muscles such as rectus femoris CSA (Sipila and Suominen, 1991;Thomaes et al., 2012). Nevertheless, the rectus femoris only represents a part of the quadriceps femoris. ...
... Force generation is closely related to muscle CSA (Akagi et al, 2009;Jubrias et al, 1997). The MT measurement using US has been closely correlated to muscle CSA (Abe et al, 1997;Sipilä and Suominen, 1991). Measurement using US to investigate the MT has been performed in both clinical and research settings (Akbari et al, 2008). ...
The purpose of the current study was to determine the intra- and inter-rater reliability of muscle thickness (MT) measurement of the psoas major (PM) using ultrasonography (US) conducted at different inward pressures of approximately .5 kg, 1.0 kg, 1.5 kg, and 2.0 kg. Twelve healthy male subjects were recruited for the study. The thicknesses of both PMs of each subject were measured by two different examiners in a random manner to assess the intra- and inter-rater reliability. The measurement values were analyzed using the intra-class correlation coefficient (ICC) with a 95% confidence interval (CI). ICC (2,1) was used to determine the inter-rater reliability and ICC (3,1) was used to assess the intra-rater reliability of the MT measurement of the PM. The results indicated higher ICC values for intra-rater reliability compared to inter-rater reliability. In addition, the value for intra-rater reliability with .5 kg inward pressure [ICC=.99 (95%CI=.98~.99)] was higher compared to 1.0 kg, 1.5 kg, and 2.0 kg. Other inward pressures for intra- and inter-rater reliability in current study were also demonstrated to have excellent values (ICC=.94~.99). These findings showed that maintaining consistent inward pressure is essential for maintaining reliability of the results when the MT of the PM is measured by different examiners in a clinical setting.
... Changes in the proportion of non-contractile intramuscular elements can be easily assessed using the non-invasive and safe method of ultrasound imaging, where an increase in image echo intensity (EI) is thought to be primarily caused by increases in fat and connective tissue (Arts et al. 2010; Pillen et al. 2009; Sipila and Suominen 1993). Early research determined the EI of the whole quadriceps femoris by a four-point scale visual analysis and reported a negative correlation between muscular EI and knee extension isometric strength (Sipila and Suominen 1991). However, visual analysis is dependent on the experience of the investigators performing the task and less sensitive in clinical evaluation than the currently available quantitative EI analysis (Pillen et al. 2006 ). ...
Increased proportion of non-contractile elements can be observed during aging by enhanced skeletal muscle echo intensity (EI). Studies have demonstrated that an increase in rectus femoris EI may affect physical performance. However, it is still unknown whether the whole quadriceps femoris EI (QEI) influences strength, power, and functional capacity of an older population. Therefore, the aim of the present study was to determine the correlation between QEI, the four individual quadriceps portions EI, and muscular performance of older men. Fifty sedentary healthy men (66.1 ± 4.5 years, 1.75 ± 0.06 m, 80.2 ± 11.0 kg) volunteered for the present study. The QEI and EI of the four quadriceps portions were calculated by ultrasound imaging. Knee extension one repetition maximum (1RM), isometric peak torque (PT), and rate of torque development (RTD) were obtained as measures of muscular strength. Muscular power was determined by knee extension with 60 % of 1RM and countermovement jump (CMJ). The 30-s sit-to-stand test was evaluated as a functional capacity parameter. QEI and all individual EI were correlated to functional capacity and power during CMJ (p ≤ 0.05), but rectus femoris EI was not related to knee extension average power (p > 0.05). There were significant correlations between all EI variables, 1RM, PT, and RTD at 0.2 s (p ≤ 0.05), but only vastus medialis EI and QEI were correlated to RTD at 0.05 s (p ≤ 0.05). The results of the present study suggest that QEI is related to muscular power and functional capacity of older subjects, but the EI of some individual quadriceps portions may underestimate the correlations with muscular performance.
... Subcutaneous fat thickness assessed via ultrasound imaging is correlated with total body fat composition (Leahy et al., 2012) which is correlated with intramuscular fat content (Brumbaugh et al., 2012). Greater intramuscular fat is associated with lesser strength due to the fact that less of the muscle's cross-sectional area is composed of contractile elements (Fukumoto et al., 2012;Sipila and Suominen, 1991, 1993, 1994. As such, the negative correlation between posterior thigh fat thickness and hamstring MTS may be attributable, in part, to greater intramuscular fat. ...
Objectives: The increased muscle activity and diminished blood supply following connective tissue changes in Oral Submucous Fibrosis (OSF) patients lead to muscle degeneration and fibrosis. The histopathological examination of OSF patients confirms fibrosis, but it also causes scarring and worsens OSF. Ultrasonography (USG) has been utilized in recent research to assess the echogenic patterns of the head and neck muscles in OSF patients. The study aimed to compare the echogenic pattern of the masseter muscle in OSF patients to that of normal mucosa using USG. Methods: The study population was split into cases and controls. The cases were 63 subjects who were clinically diagnosed with OSF. In comparison, the controls were 63 subjects who were randomly selected from the outpatient clinic of Oral Medicine and Radiology, Government Dental College, Thiruvananthapuram. According to Khanna and Andrade’s criteria, OSF subjects were divided into four groups based on their clinical findings. A high-resolution real-time LOGIQUE C5 ultrasonic scanner with 7-12MHz transducers was used to image the masseteric muscle. Results: In the present study, type II internal echogenic pattern (64.4 %) was predominant, followed by type III and type I in OSF subjects. So, type I internal echogenic patterns might be associated with normal muscles, and types II and III internal echogenic patterns might be associated with pathologic changes. A good interobserver agreement was observed. Conclusion: In OSF patients, the appearance of the masseter muscle’s internal echogenic pattern showed a varied pattern from that of normal types.
With aging comes reductions in the quality and size of skeletal muscle. These changes influence the force-generating capacity of skeletal muscle and contribute to movement deficits that accompany aging. Although declines in strength remain a significant barrier to mobility in older adults, the association between age-related changes in muscle structure and function remain unresolved. In this study, we compared age-related differences in (i) muscle volume and architecture, (ii) the quantity and distribution of intramuscular fat, and (iii) muscle shear modulus (an index of stiffness) in the triceps surae in 21 younger (24.6 ± 4.3 years) and 15 older (70.4 ± 2.4 years) healthy adults. Additionally, we explored the relationship between muscle volume, architecture, intramuscular fat and ankle plantar flexion strength in young and older adults. Magnetic resonance imaging was used to determine muscle volume and intramuscular fat content. B-mode ultrasound was used to quantify muscle architecture, shear-wave elastography was used to measure shear modulus, and ankle strength was measured during maximal isometric plantar flexion contractions. We found that older adults displayed higher levels of intramuscular fat yet similar muscle volumes in the medial (MG) and lateral gastrocnemius (LG) and soleus, compared to younger adults. These age-related higher levels of intramuscular fat were associated with lower muscle shear modulus in the LG and MG. We also found that muscle physiological cross-sectional area (PCSA) that accounted for age-associated differences in intramuscular fat showed a modest increase in its association with ankle strength compared to PCSA that did not account for fat content. This highlights that skeletal muscle fat infiltration plays a role in age-related strength deficits, but does not fully explain the age-related loss in muscle strength, suggesting that other factors play a more significant role.
This thesis has developed and utilised an inertial loading system to study human skeletal muscle power output. Specifically, the apparatus has been used to study the effects of different modes of exercise, muscle myosin isoform composition and the effects of ageing on the ability of the lower limb muscles to generate explosive power. A variable inertial loading system was designed and constructed which allowed for the sensitive detection of the rotational properties of a flywheel from which the contractile characteristics of muscle could be inferred. When housed in the Nottingham Power Rig (NPR) the peak power generated by young non-trained male subjects from a single lower limb thrust ranged from 608 - 965 Watts and was found to occur at inertial loads ranging from 0.09 - 0.22 kgm2. To investigate the low power outputs observed at the low inertial loads, where the contraction time was short, a pre release mechanism was incorporated into the flywheel assembly. Significant increases in power output of ~ 17% were achieved at the lowest inertial load (P = 0.02), if a prior build up of isometric torque was allowed prior to movement. This suggested that at the low inertial loads, without the pre release, insufficient time was allowed for the muscle to generate its maximum power output. The flywheel system was incorporated into a cycle ergometer to allow power - velocity characteristics to be examined during inertial sprint cycling. Peak power obtained in young subjects (n = 9) was significantly higher in the cycle exercise when compared with the NPR (1620 vs. 937 Watts). In contrast to the NPR where a parabolic relationship between power and inertial load was observed, during sprint cycling power plateaued above a 'critical' load. It was concluded that the repetitive acceleration of inertial loads, above this critical threshold, will always allow the expression of peak power during cycling as ultimately a velocity will be achieved which corresponds to that required for peak power generation. An analysis of the myosin heavy chain (MHC) isoform composition of the vastus lateralis muscle was performed in young and elderly male subjects (n = 14, mean age 29.4 and 73.8). The percentage MHC-II isoform composition was significantly lower in the older subjects as was the velocity at which peak power occurred (Vopt). Overall the Vopt during sprint cycling was found to be related to the percentage MHC-II composition of the vastus lateralis (R = 0 .82, P<0.001). Finally, muscle power was examined in Elite level master Olympic weightlifters (n = 54, aged 40 - 87 years) and aged matched controls. On average the weightlifters generated ~ 32% more peak power than their aged matched counterparts and required significantly higher inertial loads to express their peak power output. In spite of 'load optimisation', power declined at twice the rate of strength. The levels of power suggest a 20 year advantage for the weightlifters.
Introduction:
Contemporaneous measures of muscle architecture and force have not previously been conducted during critical illness to examine their relationship with intensive care unit (ICU)-acquired weakness.
Methods:
Ankle dorsiflexor muscle force (ADMF) with high-frequency electrical peroneal nerve stimulation and skeletal muscle architecture via ultrasound were measured in 21 adult, critically ill patients, 16 at ICU admission.
Results:
Thirteen patients were measured on 2 occasions. Among these, 10 who were measured at ICU admission demonstrated muscle weakness. Despite significant reductions in tibialis anterior (Δ = -88.5 ± 78.8 mm2, P = 0.002) and rectus femoris (Δ = -126.1 ± 129.1 mm2, P = 0.006) cross-sectional areas between occasions, ADMF did not change (100-HZ ankle dorsiflexor force 9.8 [IQR, 8.0-14.4] kg vs. 8.6 (IQR, 6.7-19.2) kg, P = 0.9).
Discussion:
Muscle weakness was evident at ICU admission. No additional decrements were observed 7 days later despite significant reductions in muscle size. These data suggest that not all ICU weakness is truly "acquired" and questions our understanding of muscle function during critical illness. Muscle Nerve, 2018.
Introducción: El proceso de envejecimiento se ve acompañado de una disminución de la masa y fuerza muscular, así como la capacidad funcional e independencia para realizar actividades básicas de la vida diaria. Revertir el deterioro físico y funcional mediante el mantenimiento de la calidad de vida relacionada con la salud es uno de los principales objetivos de la fisioterapia para el siglo XXI. Durante las últimas décadas, la práctica regular de ejercicio físico ha demostrado ser una de las actividades más importantes para mantenernos saludables a medida que envejecemos. Los métodos más frecuentemente utilizados para la práctica de ejercicio físico son el entrenamiento progresivo de la resistencia, la estimulación eléctrica neuromuscular y los programas de ejercicios multi-modales tales como el Otago Exercise Programme.
Por otro lado, la mejora de la calidad de vida relacionada con la salud también pasa por una mejora en la comprensión de los factores físicos que explican en mayor medida la deambulación y la movilidad en poblaciones de edad avanzada. Identificar estos factores permitiría a fisioterapeutas y otros profesionales de la salud incluirlos como parte de sus protocolos de evaluación, además de diseñar intervenciones adecuadas para la reducción de la pérdida de capacidad funcional como consecuencia de la edad.
Objetivos: Los objetivos de esta tesis se dividen en tres puntos. (1) Evaluar los efectos de tres programas diferentes de entrenamiento progresivo de la resistencia realizados a baja intensidad sobre la capacidad funcional, el volumen muscular y la capacidad para realizar actividades básicas de la vida diaria, en una población de adultos mayores que residentes en un centro geriátrico. (2) Evaluar los efectos de un programa de ejercicios basado en el Otago Exercise Programme en su modalidad group-based utilizando apoyo audio-visual sobre el equilibrio, la movilidad, la capacidad funcional y la resistencia aeróbica en una población de adultos mayores que habitan en la comunidad. (3) Investigar la contribución de una serie de factores demográficos y medidas físicas para explicar los resultados de las pruebas 6-minute Walk Test y Timed “Up-and-Go” Test en una muestra de adultos mayores que habitan en la comunidad y residen en un centro geriátrico.
Diseño, Participantes y Variables de estudio: Esta tesis está compuesta por un total de 4 estudios, dos estudios prospectivos (RCT) y dos estudios descriptivos transversales. La muestra de los estudios estaba compuesta por adultos mayores con edades ≥65 años residentes en un centro geriátrico (n=117) o que habitan en la comunidad (n=156). Las medidas empleadas para la evaluación de los participantes fueron las siguientes. El 6-minute Walk Test, una prueba que evalúa la distancia recorrida caminando durante un período de 6 minutos. La Berg Balance Scale, una batería de tareas para la evaluación del equilibrio funcional basada en la ejecución de actividades de la vida diaria. El Timed “Up-and-Go” Test, una prueba para la evaluación de la movilidad basada en el tiempo necesario para levantarse de una silla, caminar 3 m, rodear un cono y volver a la silla para sentarse nuevamente. El área de sección transversal muscular del músculo recto femoral medido mediante ecografía. La Short Physical Performance Battery, una batería de pruebas diseñada para la evaluación de la capacidad funcional de los miembros inferiores. La fuerza máxima de agarre medida mediante un dinamómetro hidráulico de mano JAMAR. El One-leg Stand Test, una prueba para la evaluación del equilibrio unipodal. La fuerza máxima de contracción durante la contracción isométrica de los músculos extensores de rodilla. El Barthel Index, un cuestionario para la evaluación del grado de independencia para realizar actividades básicas de la vida diaria.
Intervención: En el primer estudio, los participantes fueron aleatoriamente asignados a uno de los tres grupos de intervención: contracción voluntaria, estimulación eléctrica neuromuscular, o estimulación eléctrica neuromuscular con contracción voluntaria simultánea. La intervención estaba basada en ejercicios de flexo-extensión de rodilla realizados a una intensidad del 40% de la fuerza máxima extensora de cuádriceps medida mediante la prueba 1RM. En el segundo estudio, los participantes fueron aleatoriamente asignados a uno de los grupos intervención o control y realizaron una rutina de tres sesiones semanales de 50 minutos de duración en las que realizaron los ejercicios descritos en el programa Otago Exercise Programme con el apoyo de material audiovisual. En el tercer y cuarto estudio, a tratarse de dos estudios transversales, los participantes realizaron una única evaluación que incluía las variables de estudio descritas.
Resultados y Conclusiones: (1) Un programa basado en la aplicación de ejercicios de extensión de rodilla con estimulación eléctrica neuromuscular con contracción voluntaria simultánea a baja intensidad mejora la capacidad funcional, la sección transversal del recto femoral y la capacidad para realizar actividades básicas de la vida diaria en adultos mayores que residen en un centro geriátrico. (2) Un programa de ejercicios Otago Exercise Programme realizado en formato group-based y suplementado con material audio-visual, mejora el equilibrio, la movilidad y capacidad funcional en adultos mayores que habitan en la comunidad. (3) Mayores niveles de equilibrio, capacidad funcional en los miembros inferiores y movilidad, están asociados a una mejor capacidad para la deambulación en los adultos mayores. (4) El equilibrio funcional medido mediante la Berg Balance Scale es la prueba que explica en mayor grado la movilidad en poblaciones de adultos mayores. (5) El deterioro de la capacidad para la deambulación y la movilidad pueden explicarse como resultado de la suma de déficits en diferentes capacidades, y no como consecuencia del deterioro de una única capacidad.
Palabras Clave: Resistance exercise, Neuromuscular electrical stimulation, Physical performance, Randomized controlled trial, Otago exercise programme, Community dwelling, 6-minute walk test, Mobility, Timed “Up-and-Go” test, Aging, Older adults.
The factors influencing ankle range of motion were investigated for 185 middle-aged and elderly subjects (116 women and 69 men, aged 48-86 years) . Each subject was seated with the right knee extended, and the ankle joint was passively dorsiflexed by a dynamometer with torque just tolerable for each subject, to measure the maximal dorsiflexion angle. During passive loading, elongation of muscle fibers in the gastrocnemius and Achilles tendon was determined in vivo by ultrasonography. There was a difference between women and men for the passive dorsiflexion angle (men smaller than women), which negatively correlated with muscle thickness of the posterior portion of the leg determined by ultrasonography. Both in women and men, the passive dorsiflexion angle negatively correlated with age, even after normalizing for maximal voluntary plantar flexion torque. Both elongation of muscle fibers and tendon was related to the passive dorsiflexion angle, and the ratio of tendon elongation to muscle fiber elongation positively correlated with the passive dorsiflexion angle. The active dorsiflexion angle, measured separately with the subject maximally dorsiflexing the ankle with no load, correlated with the passive dorsiflexion angle but not with age, and there was no gender difference. From the results it was suggested 1) that the mobility of the ankle joint is affected by elongation of both muscle fibers and tendon, but with the effect of the tendon being greater than that of muscle fibers, and 2) that muscle mass negatively affects passively-induced joint range of motion. Actively performed joint range of motion would be affected by elongation of the muscle-tendon corn plex and force-generating capability of the ankle. Gender difference in joint range of motion and the aging effect are related to these factors.
Physical activity recommendations for public health include typically muscle-strengthening activities for a minimum of 2 days a week. The range of inter-individual variation in responses to resistance training (RT) aiming to improve health and well-being requires to be investigated. The purpose of this study was to quantify high and low responders for RT-induced changes in muscle size and strength and to examine possible effects of age and sex on these responses. Previously collected data of untrained healthy men and women (age 19 to 78 years, n = 287 with 72 controls) were pooled for the present study. Muscle size and strength changed during RT are 4.8 ± 6.1 % (range from −11 to 30 %) and 21.1 ± 11.5 % (range from −8 to 60 %) compared to pre-RT, respectively. Age and sex did not affect to the RT responses. Fourteen percent and 12 % of the subjects were defined as high responders (>1 standard deviation (SD) from the group mean) for the RT-induced changes in muscle size and strength, respectively. When taking into account the results of non-training controls (upper 95 % CI), 29 and 7 % of the subjects were defined as low responders for the RT-induced changes in muscle size and strength, respectively. The muscle size and strength responses varied extensively between the subjects regardless of subject’s age and sex. Whether these changes are associated with, e.g., functional capacity and metabolic health improvements due to RT requires further studies.
The relationship between bone and skeletal muscle mass may be affected by physical training. No studies have prospectively examined the bone and skeletal muscle responses to a short controlled exercise-training programme. We hypothesised that a short exercise-training period would affect muscle and bone mass together.
Femoral bone and Rectus femoris Volumes (RFVOL) were determined by magnetic resonance imaging in 215 healthy army recruits, and bone mineral density (BMD) by Dual X-Ray Absorptiometry (DXA) and repeated after 12 weeks of regulated physical training.
Pre-training, RFVOL was smaller in smokers than non-smokers (100.9 ± 20.2 vs. 108.7 ± 24.5, p = 0.018; 96.2 ± 16.9 vs. 104.8 ± 21.3, p = 0.002 for dominant/non-dominant limbs), although increases in RFVOL with training (of 14.2 ± 14.5% and 13.2 ± 15.6%] respectively, p < 0.001) were independent of prior smoking status. Pre-training RFVOL was related to bone cortical volume (r(2) = 0.21 and 0.30, p < 0.001 for dominant and non-dominant legs), and specifically to periosteal (r(2) = 0.21 and 0.23, p < 0.001) volume. Pre-training dominant RFVOL was independently associated with Total Hip BMD (p < 0.001). Training-related increases in RFVOL and bone volumes were related. Whilst smokers demonstrated lower muscle mass than non-smokers, differences were abolished with training. Training-related increases in muscle mass were related to increases in periosteal bone volume in both dominant and non-dominant legs.
The purpose of this study was to examine the reliability of ultrasound (US) measures of cross-sectional area (CSA), muscle thickness (MT) and echo intensity (EI) of the hamstrings, with comparisons between males and females. In 20 healthy participants (10 males, 10 females), CSA, MT and EI were measured from panoramic US scans of the hamstrings on 2 separate days. The intra-class correlation coefficients and standard errors of measurement as a percentage of the mean for CSA, MT and EI ranged from 0.715 to 0.984 and from 3.145 to 12.541% in the males and from 0.724 to 0.977 and from 4.571 to 17.890% in the females, respectively. The males had greater CSAs and MTs and lower EIs than the females (p = 0.002-0.049), and significant relationships were observed between CSA and MT (r = 0.714-0.938, p ≤ 0.001-0.023). From an overall reliability standpoint, these findings suggest that panoramic US may be a reliable technique for examining muscle size and quality of the hamstrings in both males and females.
Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.
The applications of ultrasound in managing the clinical care of athletes have been expanding over the past decade. This review provides an analysis of the research that has been published regarding the use of ultrasound in athletes and focuses on how these emerging techniques can impact the clinical management of athletes by sports medicine physicians.
Electronic database literature searches were performed using the subject terms ‘ultrasound’ and ‘athletes’ from the years 2003 to 2012. The following databases were searched: PubMed, Web of Science, Cochrane Library, CINAHL, and SPORTDiscus™. The search produced 617 articles in total, with a predominance of articles focused on cardiac and musculoskeletal ultrasound. 266 of the studies involved application of ultrasound in evaluating the cardiovascular properties of athletes, and 151 studies involved musculoskeletal ultrasound. Other applications of ultrasound included abdominal, vascular, bone density and volume status.
New techniques in echocardiography have made significant contributions to the understanding of the physiological changes that occur in the athlete’s heart in response to the haemodynamic stress associated with different types of activity. The likely application of these techniques will be in managing athletes with hypertrophic cardiomyopathy, and the techniques are near ready for application into clinical practice. These techniques are highly specialized, however, and will require referral to dedicated laboratories to influence the clinical management of athletes. Investigation of aortic root pathology and pulmonary vascular haemodynamics are also emerging, but will require additional studies with larger numbers and outcomes analysis to validate their clinical utility. Some of these techniques are relatively simple, and thus hold the potential to enter clinical management in a point-of-care fashion.
Musculoskeletal ultrasound has demonstrated a number of diagnostic and therapeutic techniques applicable to pathology of the shoulder, elbow, wrist, hand, hip, knee and ankle. These techniques have been applied mainly to the management of impingement syndromes, tendinopathies and arthritis. Many of these techniques have been validated and have entered clinical practice, while more recently developed techniques (such as dynamic ultrasound and platelet-rich plasma injections) will require further research to verify efficacy. Research in musculoskeletal ultrasound has also been helpful in identifying risk factors for injury and, thus, serving as a focus for developing interventions.
Research in abdominal ultrasound has investigated the potential role of ultrasound imaging in assessing splenomegaly in athletes with mononucleosis, in an attempt to inform decisions and policies regarding return to play. Future research will have to demonstrate a reduction in adverse events in order to justify the application of such a technique into policy. The role of ultrasound in assessing groin pain and abdominal pain in ultraendurance athletes has also been investigated, providing promising areas of focus for the development of treatment interventions and physical therapy.
Finally, preliminary research has also identified the role of ultrasound in addressing vascular disease, bone density and volume status in athletes. The potential applications of ultrasound in athletes are broad, and continuing research, including larger outcome studies, will be required to establish the clinical utility of these techniques in the care of athletes.
The purpose of the current study was to examine muscle characteristics of the vastus lateralis (VL) and body composition of NCAA Division I football players. Sixty-nine Division I football players (Mean±SD; Age: 20.0±1.1 yrs; Height: 186.2±7.0 cm; Body mass: 106.3±21.1 kg; %fat: 17.8±4.6 %) were stratified by player position, race, year and starter status. A panoramic scan of the VL was performed using a GE logiq-e B-mode ultrasound (US). Muscle cross-sectional area (mCSA) and echo intensity (EI) were determined using Image-J software from the VL scan. Body composition measures were determined using dual-energy x-ray absorptiometry (DXA). For mCSA, defensive linemen (DL; 46.7±4.2 cm) had significantly greater CSA (p<0.05) than wide receivers (WR), linebackers (LB), defensive backs (DB), punters/kickers (PK) and running backs (RB). There were no significant differences for EI (p>0.05) between positions. Offensive linemen (OL) and DL had significantly greater %fat than WR, LB, DB, PK, and RB (p<0.05); greater lean mass than all other positions (p<0.05); as well as more fat mass than quarterbacks (QB), WR, LB, DB, PK, and RB (p<0.05). There were no muscle or body composition differences for race, year, or starter status. As no differences between positions were observed for EI measures, it may indicate competitive athletes have increased muscle quality regardless of body composition differences. US and DXA measures may be useful to identify muscle characteristics and imbalances if a player gains or loses weight, suffers an injury, or declines in performance.
Since ultrasound has different reflections depending on components of organization, analysis of ultrasound images of skeletal muscle can offer both quantitative and qualitative reports as concerns skeletal muscle structure. This study is focused on the ultrasound method for evaluating the structural characteristics of skeletal muscle and also conducted to examine its practicality. After obtaining images of the elbow flexors from an ultrasound image device with 88 normal subjects whose ages were between twenty and seventy years old (44 men and 44 women), muscular density and white area index (WAI) which indicated structural characteristics of skeletal muscle were analyzed with gray scale analysis. The study examined correlations between subject's age and items which obtained from measuring ultrasound images and the differences in relations to sex and age. Muscular density and WAI had a high correlation with age and were significantly increased in men and women with greater age. The quantitative evaluation method of skeletal muscle structure which analyzed the ultrasound images has high practicality because it is a non-invasive method which complements physical therapy diagnosis and research methods and promotes functionality evaluation.
New Findings
What is the central question of this study?
The study examined the relationship between muscle size and strength in chronic obstructive pulmonary disease (COPD) patients as well as young and elderly healthy control subjects. We hypothesized that ankle dorsiflexor muscle strength would be reduced by COPD as well as by ageing, and that this would be as a result of changes in both size and composition of the muscle.
What is the main finding and its importance?
These data demonstrate that the loss of skeletal muscle strength in COPD was related to changes in muscle composition, with infiltration of non‐contractile tissue beyond that seen during normal ageing.
Loss of skeletal muscle strength is a well‐recognized feature of ageing and chronic obstructive pulmonary disease (COPD). Reductions in muscle size provide only a partial explanation for this loss of strength, and additional contributory factors remain undetermined. We hypothesized that reductions in skeletal muscle strength, as measured in the ankle dorsiflexor muscles, would be reduced with ageing and COPD as a result of changes in both size and composition of the tibialis anterior muscle. Twenty healthy young subjects, 18 healthy elderly subjects and 17 patients with COPD were studied. Ankle dorsiflexor muscle strength was assessed by maximal voluntary contraction (ADMVC) and 100 Hz supramaximal electrical stimulation of the peroneal nerve (100 HzAD). Tibialis anterior cross‐sectional area (TA CSA ) and composition, as assessed by echo intensity (TA EI ), were measured using ultrasonography. Despite a lack of differences in TA CSA between groups, ADMVC and 100 HzAD were significantly reduced in COPD patients compared with both healthy elderly and healthy young subjects, when expressed as absolute values and when normalized to TA CSA ( P < 0.01). The TA EI was, however, higher in COPD patients compared with healthy elderly ( P = 0.025) and healthy young subjects ( P = 0.0008), suggesting increased levels of non‐contractile tissue. Across all participants, ADMVC and 100 HzAD correlated positively with TA CSA ( r = 0.78, P < 0.0001) and negatively with TA EI ( r = −0.46, P < 0.0005). The variance in 100 HzAD was best explained with a regression model incorporating TA CSA , TA EI , age and COPD status ( r ² = 0.822, P = 0.001). These data demonstrate that the loss of skeletal muscle strength in COPD is related to changes in muscle composition, with infiltration of non‐contractile tissue beyond that seen during normal ageing.
Introduction:
In this study we examined the test-retest reliability of panoramic brightness-mode ultrasound (US) imaging to simultaneously measure both muscle size and quality from a single US image.
Methods:
Sixteen healthy, recreationally active men (age = 20.9 ± 2.5 years) volunteered for this investigation. Test-retest reliability was evaluated using intraclass correlation coefficients (ICCs) and the standard error of measurement as a percentage of the mean (SEM%). Muscle size [cross-sectional area (CSA)], and muscle quality [echo intensity (EI)] of the medial gastrocnemius were examined on 2 separate days.
Results:
These measures demonstrated acceptable reliability between assessment days with ICCs and SEM% of 0.914 and 0.720 and 5.830 and 3.680 for CSA and EI, respectively.
Conclusions:
These results suggest that panoramic US imaging may be a reliable technique for simultaneous assessment of both muscle size and quality from a single US scan.
In order to study the effects of increasing age on the human skeletal muscle, cross-sections (15 micron) of autopsied whole vastus lateralis muscle from 43 previously physically healthy men between 15 and 83 years of age were prepared and examined. The data obtained on muscle area, total number, size, proportion and distribution of type 1 (slow-twitch) and type 2 (fast-twitch) fibers were analysed using multivariate regression. The results show that the ageing atrophy of this muscle begins around 25 years of age and thereafter accelerates. This is caused mainly by a loss of fibers, with no predominant effect on any fiber type, and to a lesser extent by a reduction in fiber size, mostly of type 2 fibers. The results also suggest the occurrence of several other age-related adaptive mechanisms which could influence fiber sizes and fiber number, as well as enzyme histochemical fiber characteristics.
The effects of aging on the total number and size of fibers, and the proportion and distribution of type 1 (slow twitch) and type 2 (fast twitch) fibers were studied in cross sections (15 mu thick) of autopsied whole m. vastus lateralis from two age groups. Each group consisted of six, previously physically healthy males (mean age 72 +/- 1 years and 30 +/- 6 years, respectively). The size of the muscles of the older individuals was 18% smaller (P less than 0.01) and the total number of fibers was 25% lower (P less than 0.01) than those of the young individuals (mean number 364,000 +/- 50,000 vs 478,000 +/- 56,000). There was, however, no significant difference in the mean fiber size (indirectly determined) or the proportion of the two fiber types, though a preferential reduction in type 2 fiber number in the aged individuals was seen. The relative occurrence of the fiber types at various depths in the aged muscles was found to be more even than in muscles from the young individuals. The results suggest that the aging atrophy in m. vastus lateralis, at least up to the age of 70, is primarily the result of a loss of fibers.
This article has no abstract; the first 100 words appear below.
(First of Two Parts) SINCE the introduction of gray-scale signal processing in 1974, B-scan sonography has become a widely accepted method for noninvasive imaging of nearly all abdominal and pelvic viscera. Results in varied clinical settings have proved sonography an accurate, versatile and inexpensive technic yielding high-resolution cross-sectional tomographic images with negligible risk or discomfort. Useful diagnostic contributions of high-frequency ultrasound imaging had been demonstrated several years earlier for special problems in obstetrics, cardiology and ophthalmology. However, broader clinical applications awaited the advent of the wide-dynamic-range (gray-scale) display for enhanced texture information of solid parenchymatous organs. Concomitant advances in transducer . . .
*Ultrasound display modes: A-Mode (amplitude modulation), echoes displayed as vertical deflections along an oscilloscope base line with echo height proportional to amplitude: B-Mode (brightness modulation), echoes displayed as individually illuminated dots along an oscilloscope base line with echo brightness proportional to amplitude; B-Scan, B-mode display with location and direction of oscilloscope base line following the transducer for two-dimensional imaging; and M-Mode (motion), A-mode display with continuous movement of base line for timed exposure with film or light-sensitive paper.
Source Information
From the Department of Radiology, Massachusetts General Hospital, Boston, MA 02114, where reprint requests should be addressed to Dr. Ferrucci.
Isometric and dynamic strength and endurance of knee extensors were tested in 18 young males. The relative composition of slow (ST) and fast twitch (FT) fibers in the vastus lateralis muscle was registered from needle biopsies. Thigh muscle volume was evaluated from ultrasonic measurements. Six subjects served as controls, six trained with 50%, and six with 80% dynamic strength three times per week for 7 weeks with 20 and 12 repetitions per session, respectively. The training load was adjusted to the increases in strength observed during training. Dynamic strength increased by 42.3% in the 80% group (p< 0.01). In the control group and 50% group no significant increases were observed. Dynamic endurance: Controls showed no change. There was an over-all increase in the 50% group, while the 80% group only increased dynamic endurance for heavier loads. Isometric strength and endurance and fiber composition did not change in any group. In the 50% group the area of FT-realtive to ST-fibers increased 12.4% (p>0.05). Dynamic strength relative to muscle cross section increased by 30% in the 80% group (p<0.01) positively correlated to relative content of FT fibers.
The present results confirm the specificity of training and indicate that a high content of FT fibers is a prerequisite for a successful strength training.
Five one-hour exercise periods a week for 8 weeks included walking-jogging, swimming, gymnastics and ballgames for 26 healthy male and female 69-year-old pensioners. The mean maximal oxygen uptake of the men increased from 28.9 ml-kg-1-min-1 before training to 32.0 ml-kg-1-min-1 after training and for the women from 27.9 to 31.3 ml-kg-1-min-1. Muscle malate dehydrogenase activity was increased while that for lactate dehydrogenase decreased or remained the same. The activity of these enzymes was higher in the male both before and after training when compared with the female. However, the percentage number of slow twitch muscle fibers was nearly the same in both groups. Prolyl hydroxylase activity was increased after training especially in the female subjects. These results show that endurance-type training leads to an enhanced capacity for aerobic metabolism in older subjects and that collagen metabolism in skeletal muscles is affected by physical training.
The effects of 8 weeks' endurance training on muscle metabolism at rest and after a submaximal bicycle ergometer exercise were studied in 31 previously sedentary men, aged 56-70. Training consisted of 3-5 one hour exercise bouts per week including walking-jogging, swimming, gymnastics and ball games. The effects of training were similar to those previously reported for younger men. Mean maximal oxygen uptake increased (11%), as did the resting values for muscle glycogen concentration, the enzymes representing aerobic energy metabolism (malate dehydrogenase, succinate dehydrogenase), and also some of the anaerobic enzymes (creatine phosphokinase, lactate dehydrogenase). Lactate production during submaximal work decreased. The enzyme activities were lower following acute exercise both before and after training.
A prospective study was done on 222 consecutive new patients referred to our pediatric muscle clinic to assess the diagnostic value of ultrasound imaging. Ultrasound scans were interpreted without knowledge of clinical presentation or results of other tests. Muscular dystrophy produced a brightly speckled pattern of increased echo from the muscle, whereas spinal muscular atrophy showed a moderate increase in muscle echo and associated muscle atrophy. Acute dermatomyositis produced a moderate increase in echo that varied markedly with the direction of the ultrasound beam in relation to the muscle fibres. The ultrasound scan was normal in children with hypotonia of cerebral origin, Prader Willi syndrome, ligamentous laxity, and other "nonneuromuscular" causes. In eight patients ultrasound scanning showed a striking degree of selective involvement of individual components of the quadriceps muscle, which provided considerable diagnostic help for selective needle biopsy. Ultrasound scanning in children has the major advantage of being a noninvasive and pleasant out-patient procedure, which can be readily done on multiple sites. It is a valuable screening test in the investigation of children with neuromuscular disorders.
Intramuscular collagen in a slow (m. soleus) and a fast (m. rectus femoris) skeletal muscle was studied by biochemical, morphometric, and immunohistochemical methods. Wistar white rats of 1, 4, 10, and 24 months were used as experimental animals. Our aim was to evaluate the effects of life-long physical training (treadmill running, 5 days a week for 1, 3, 9, and 23 months depending on the age attained). The biochemical concentration of collagen was higher in m. soleus than in m. rectus femoris and it increased in youth and in old age in m. soleus. The trained rats had higher concentrations of collagen than the untrained rats at 10 and 24 months. The morphometrically measured area-fractions of both the endomysium and perimysium were higher in m. soleus than in m. rectus femoris. The age-related increase in intramuscular connective tissue was of endomysial origin. The immunohistochemical staining of type-I, -III, and -IV collagens indicated the more collagenous nature of m. soleus as compared with m. rectus femoris for all major collagen types; this was most marked for type-IV collagen of basement membrane. The results indicate that both age and endurance-type physical training further distinguish the slow and fast muscles with respect to their connective tissue.
Two groups of human subjects were submitted to a 20-week endurance training program (1 h a day, 4 days a week, 70-80% max VO2). The first group (G20) consisted of eight 22 +/- 3 years male students, the second group (G60) was composed of seven still very physically active elderly male subjects (62 +/- 4 years). Training significantly increased max VO2 by 15% in G20 and 7% in G60. Muscle samples taken from the vastus lateralis muscle before and after training were histochemically stained for fibre-typing (myofibrillar ATPase), capillary supply and fibre area measurements (amylase PAS and NADH-TR). Fibre-type distribution was unchanged with training. Capillary density (cap X mm-2) increased significantly in both groups from 316 +/- 42 to 396 +/- 73 in G20 and from 308 +/- 48 to 409 +/- 55 in G60. This enhancement of capillary supply was linked to the proliferation of capillaries in G20 where the number of capillaries in contact with ST and FTa fibres (CC) significantly increased from 4.6 to 5.9 and from 4.8 to 6.1 respectively. No significant changes in fibre areas were found in G20. On the contrary, G60 did not show any significant sign of capillary growth (CC unchanged) whereas fibre areas significantly decreased in ST (6,410 to 5,520 micron 2) and FTa fibres (5,830 to 5,090 micron 2). A methodological evaluation of fibre-area measurement was described, with confirmation of the data. It was concluded that this study may illustrate the trainability of skeletal muscle of elderly men in a possibly different way to that seen in a younger age group.
A follow-up study of muscle strength, muscle morphology, and enzymatic activity in 23 men, 73-83 years of age, was performed 7 years after the first investigation. With the exception of two men treated for congestive heart failure and four treated for hypertension, all were apparently clinically healthy and none had functional locomotor disturbances. Body weight was reduced by 2% and body cell mass by 6%, whereas the quadriceps muscle strength decreased 10%-22% over the 7-year period. Fiber composition in the vastus lateralis did not change significantly, and there was no significant difference between the biopsies from the biceps brachii and vastus lateralis. In the vastus lateralis, there was a reduction in fast-twitch fiber areas, which were smaller than in the biceps brachii (not studied at the previous investigation). There were also more histopathologic changes in the vastus lateralis than in the biceps brachii. The enzymatic activities of lactate dehydrogenase and myokinase, which were studied on both occasions in the vastus lateralis, did not change, and the activities of the other measured enzymes indicated a maintained metabolic capacity at high age. Oxidative enzymatic activities were higher in the vastus lateralis, and glycolytic enzymatic activities were higher in the biceps brachii, which could partly be explained by differences in relative fiber areas.
The mean isometric strength of the stronger quadriceps muscles of 12 healthy men in their seventies was 39% less than that of 12 healthy men in their twenties (P less than 0.001). The cross-sectional area of the quadriceps was measured at mid-thigh, by ultrasound scanning; the older men's stronger quadriceps were 25% smaller (P less than 0.001). The ratio of the stronger quadriceps' strength to its cross-sectional area was very similar in the old men to values obtained previously for both old and young women, but averaged 19% less than in the young men (P less than 0.02). Quadriceps size and strength were correlated in the old men (r = 0.77, P = 0.03) but not in the young men (r = 0.15). The principal axis of the relationship between quadriceps size and strength in the old men was very similar to those previously reported for both old and young women. The quadriceps strength of some young men is greater than would be expected from the size of the muscle.
Skeletal muscle was obtained from the vastus lateralis of three normal college male students. Two biopsies were obtained prior to a training period and one after the training period. Subjects participated in an intense weight training program involving isometric and isotonic exercises. The subjects participated in the exercise regimen five days in each week for a period of 10 weeks. Muscle tissue was processed immediately for electron microscope examination. The following parameters were measured from micrographs of longitudinal sections: sarcomere length, sarcomere width, intracellular fat, mitochondria number and mitochondria length. The following parameters were measured from micrographs of cross sections: myosin filament concentration, distance between myosin filaments, myosin filament diameter, the number of actin filaments in orbit around a myosin filament, and gross cell size. Major findings included significant changes in myosin filament concentration, distance between myosin filaments, and the number of actin filaments in orbit around a myosin filament.
A comparative study of the ultrasound appearances of the thigh with the static B scan showed consistent differences in 10 children with muscular dystrophy compared with 40 healthy controls. This non-invasive technique could be useful in assessing the extent of pathological change in dystrophic patients and could prove a valuable diagnostic aid.
Muscle weakness and wasting may be evaluated objectively by dynamometry and compound ultrasound imaging. We have measured the voluntary isometric strength of the quadriceps muscles of healthy women in their 70s ( n = 25) and in their 20s ( n = 25) and have compared it with the mid‐thigh cross‐sectional area of the same muscles.
The two groups of women showed similar variability when strength was measured on consecutive days (coefficients of variation: 8%). The older women were 35% weaker than the young women ( P < 0·001) and their quadriceps cross‐sectional area was 33% less ( P < 0·001). Quadriceps strength and cross‐sectional area were correlated ( r = 0·66, P < 0·001, elderly; r = 0·53, P < 0·01, young) and the principal axis of the relationship was closely similar for the two groups of women. There is therefore no difference in the intrinsic strength of the quadriceps muscles of healthy women in their third and eighth decades.
This report also provides normative data for the objective evaluation of quadriceps weakness and/or wasting in female patients. The techniques involved are straightforward, the dynamometer is easily made, and compound ultrasound imaging is widely available.
The centrally directed axonal processes of the distal vagal ganglion cells were cut by midcervical vagotomy in nine domestic fowl, and the ganglion cells were examined electron microscopically after intervals of 5-462 days. During the first 5-41 days after operation, peripheral displacement of the nucleus, indentation of the nuclear membrane, dilation of the cisternae of the granular endoplasmic reticulum, depletion of membrane associated ribosomes, and peripheral displacement and fragmentation of the Golgi apparatus were found. These changes are interpreted as reactive responses to the axonal injury. From 207 days onwards, general loss of organelles and extensive vacuolation of the cytoplasm were observed. These changes were regarded as severely degenerative, to the point of cell death. Between 305 and 462 days many ganglion cells were lost, the few survivors apparently being normal except for numerous nuclear pores. Degenerative changes were also seen in satellite cells. It is concluded that severance of the central processes of the distal vagal ganglion cells of this avian species leads to the slow development of reactive and degenerative changes in many of the ganglion cells. These results are compared with those of similar experiments on mammals, in which the sensory ganglion cells appear to be totally unresponsive to the interruption of their centrally directed processes.
Nine-teen men and twenty-one women, regarded as representative for the healthy seventy-five-year-old urban population were subjected to tests of lower and upper extremity function. The results were compared with those in the same probands at the age of 70. The investigation included tests of muscular isometric and isokinetic strength in knee-extension and flexion, isometric strength in key-grip, transversal volar grip, elbow-extension and flexion. Furthermore muscular coordination in hand and arm and submaximal endurance in hand-grip were measured. The subjects were classified with regard to physical activity. Between the age of 70 and 75 there was a significant decline in muscle strength in both sexes in the knee-extensors and a somewhat smaller in isometric than in isokinetic strength, and a decline also in the elbow-extensors and flexors. In a test of muscular coordination of the upper extremities and of maximal strength and submaximal endurance in hand-grip the results did not differ significantly between the age of 70 and 75. Isokinetic muscle strength in the knee-extensors and flexors was higher in men with a higher level of physical activity than in those with a lower activity. The results may indicate that the decrement of muscle strength in this age in part may be based on a changed activity pattern (note lack of change in hand-grip strength) with lack of fast and forceful movements in the daily living and speaks for the desirability that elderly people be physically active and that this may prevent disability.
Computed tomography scans were taken of 21 middle-aged men (M age 46.3 years) and 20 older men (M age 69.4 years) to measure
differences in body composition with age. Overall, the older men weighed 8.2 kg less than the middle-aged men, and this difference
was primarily the result of their having less lean tissue. Although fat mass was only slightly less in older men, there were
clear distributional differences in fat between the age groups. Total abdomen fat area was similar in both groups, although
the subcutaneous portion of the abdomen fat was less in the older men, and they had correspondingly greater intra-abdominal
fat. Muscle areas of the leg and arm were significantly less in the older men, as were all lean tissues of the abdomen and
chest. Analysis of fat accumulation between muscles of the abdomen and leg indicated fat infiltration into lean tissue in
the older men. Causes of this apparent fat redistribution and lean body mass decline with age are presently unknown.
We describe a noninvasive quantitative way of measuring muscle with a specially-designed digital ultrasound scanner. Reliability and reproducibility of echo amplitude were determined in 16 normal male volunteers--10 runners and 6 non-runners. Echo amplitudes were recorded from the quadriceps femoris muscle. The muscle was scanned at mid-thigh in a relaxed state with 18 degrees flexion and in an isometrically contracted state with the leg in full extension. Echo amplitudes obtained in the non-runner group were: (1) mean value of the muscle in the relaxed state (174.9 +/- 30.8) and (2) mean value of the muscle in the contracted state (121.8 +/- 31.4). The difference in these values (53.1) was significant at p less than 0.05. Echo amplitudes for runners were: (1) mean value of the muscle in the relaxed state (146.6 +/- 39.2) and (2) mean value of the muscle in the contracted state (107.1 +/- 30.1). The difference in these values (39.5) was significant at p less than -0.01. The data indicate that: values of echo amplitudes are reproducible; there is a statistically significant difference in the mean amplitudes of muscle in a contracted and relaxed state; and while the difference between runner and non-runner muscle is not statistically significant (p greater than 0.1), there is a trend toward significance. Because ultrasound amplitude is a function of tissue structure, this technique may provide a noninvasive method for quantifying muscle collagen and fat.
The purpose of this pilot study was to investigate the influence of physical training on muscle morphology and strength in different age groups in order to learn about the exogenous influence (e.g., inactivity) on the these characteristics in old age. Eighteen sedentary males ranging in age from 22-65 yr were involved in a low resistance and high repetition strength training program twice a week for 15 wk. Muscle biopsies were taken and strength measurements were performed before and after the training period. Age-related muscle fiber atrophy, seen before training, was diminished after the training period because of an increase in fiber size in older subjects. Muscular strength values, however, were lower with increasing age before and after training, indicating that strength decline in old age is not primarily due to muscle fiber atrophy.
SUMMARY Grey-scale ultrasonography can produce an image of the quadriceps muscle from which it is possible to measure its cross-sectional
area (CSA). The between-days coefficient of variation for quadriceps CSA (at mid-thigh) in 14 legs of seven subjects each
scanned on four days was reduced to 4.0% by averaging four scans on each day.
Bilateral scans (at the mid-thigh level) were used to measure the severity of quadriceps wasting in 21 otherwise healthy adult
patients with a difference in thigh circumference following unilateral knee immobilization or injury.
Quadriceps wasting as demonstrated by the scans was consistently more severe than the disparity in whole thigh cross-sectional
area at the same level or the disparity in anthropometric estimates of fat-free thigh volume. Investigations concerned with
changes in quadriceps muscle bulk must therefore use a technique (such as ultrasonography) which allows measurement of the
quadriceps itself.
The time course of strength gain with respect to the contributions of neural factors and hypertrophy was studied in five young
men and five older men during the course of 8 weeks progressive strength training. Young and old men showed similar and significant
percentage increases in strength. However, the neurophysiological adaptations in response to the training were quite different,
increases in maximal muscle activation (neural factors) played a dominant role throughout the training for old subjects, while
young subjects showed strength gains due to neural factors only at the initial stage, with hypertrophy becoming the dominant
factor after some 4 weeks of training. Our data suggest that the effect of muscle training in the old may entirely rest on
the neural factors presumably acting at various levels of the nervous system which could result in increasing the maximal
muscle activation level in the absence of significant hypertrophy.
Grip strength and fat-free mass (FFM) were measured in 158 men and 112 women of 65 years and over living at home. There was
a striking decline in grip strength with increasing age in both men and women. A marginal decline in FFM was not statistically
significant. Multiple regression analysis suggested that age had an effect on grip strength which was independent of FFM.
An explanation for this pattern might be that with ageing an increasing proportion of skeletal muscle is replaced by fibrous
tissue, so that, although there is striking reduction in muscle power, there is only a marginal reduction in FFM.