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The effect of three different levels of footwear stability on pain outcomes in women runners: A randomised control trial
Abstract and Figures
The present study examines the injury status in women runners who are randomised to receive a neutral, stability or motion control running shoe.
81 female runners were categorised into three different foot posture types (39 neutral, 30 pronated, 12 highly pronated) and randomly assigned a neutral, stability or motion control running shoe. Runners underwent baseline testing to record training history, as well as leg alignment, before commencing a 13-week half marathon training programme. Outcome measures included number of missed training days due to pain and three visual analogue scale (VAS) items for pain during rest, activities of daily living and with running.
194 missed training days were reported by 32% of the running population with the stability shoe reporting the fewest missed days (51) and the motion control shoe (79) the most. There was a significant main effect (p<0.001) for footwear condition in both the neutral and pronated foot types: the motion control shoe reporting greater levels of pain in all three VAS items. In neutral feet, the neutral shoe reported greater values of pain while running than the stability shoe; in pronated feet, the stability shoe reported greater values of pain while running than the neutral shoe. No significant effects were reported for the highly pronated foot, although this was limited by an inadequate sample size.
The findings of this study suggest that our current approach of prescribing in-shoe pronation control systems on the basis of foot type is overly simplistic and potentially injurious.
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... These studies generally involve much greater numbers of participants (at least several hundred) and follow up over several months in an observational study 14,30 or a randomized trial. 15,31,32 The latter design has the advantage of randomization, which allows for an equal distribution among study groups of all other factors that may influence injury risk. Observational cohort studies and randomized trials make it possible to study the long-term effects of personal characteristics, training behavior, or a given shoe type on running injury. ...
... A similar approach was applied in a cohort of female runners, and again, the results did not support the approach, although the sample size was limited (n ¼ 81) and the outcome was pain level (measured on a visual analog scale). 32 So far, no evidence indicates that prescribing shoes according to foot morphology reduced the injury risk. However, this does not mean that individual shoe features such as motion-control and shock-absorption systems are irrelevant in the context of injury prevention. ...
... Abnormal plantar pressure leads to discomfort in at feet, which, if left untreated, will produce pain and disability 49 . The available evidence in the literature is weak with regards to the association between FO-related improved motion control and reduced injury rates in individuals with pronated feet 50 . It has been hypothesized that the acquired at foot and excessive rearfoot motion regularly seen in in ammatory conditions such as rheumatoid arthritis 51,52 are related to ultrasound and MRI con rmed features of joint and tendon damage, particularly those involved in controlling the frontal plane motion of the foot 53,54 . ...
Foot orthoses (FO) are frequently used medical devices to correct lower limbs malalignment in the form of excessive foot pronation. This systematic review with meta-analysis aimed to investigate the effects of short-term FO application on walking kinematics and kinetics in adults aged ≥18 years with excessive foot pronation. Five electronic databases (MEDLINE, Scopus, PubMed, EMBASE, and Cochrane Central Register of Controlled Trials [CENTRAL]) were systematically searched from inception to January 2024. According to the PICOS approach, the eligibility criteria were: (P) healthy participants with pronated feet, (I) short-term FO interventions (one session), (C) other walking conditions (e.g., barefoot, only shoe, fake foot orthosis), (O) lower limbs kinematics (e.g., rearfoot eversion) and kinetics (e.g., knee joint moments) during walking, and (S) case-control studies, cross-sectional studies, randomized control trials, cohort studies, and case series designs. The modified version of the Downs and Black checklist was used to assess the methodological quality. Between-group standardized mean differences (SMDs) with 95% confidence intervals (CI) were computed using a random-effects model to elucidate the effects of short-term FO compared to controls. Statistical significance was set at p<0.05. The heterogeneity between studies was assessed using the I2 index. Twenty-two studies were identified and meta-analyzed. Overall, the methodological quality of the included studies was moderate, with 15 studies achieving high-quality and the remaining seven moderate quality. For kinematics, the meta-analysis showed significant effects of short-term FO application during walking on peak rearfoot eversion (nine studies: moderate SMDs=0.66, 95% CI 0.34 to 0.99), peak ankle dorsiflexion (five studies: small SMDs=-0.33, 95% CI -0.54 to -0.12), and eversion (seven studies: moderate SMDs=0.58, 95% CI 0.27 to 0.90). Concerning kinetics, the meta-analysis indicated significant effects of short-term FO application on the peak ankle eversion moment (five studies: small SMDs=0.38, 95% CI 0.17 to 0.59) and the peak knee adduction (six studies: small SMDs=-0.30, 95% CI -0.50 to -0.10). Study heterogeneity ranged from I² = 0-87%. Our meta-analysis showed significant effects of short-term FO application on the rearfoot eversion angle during walking in adults aged ≥18 years. Accordingly, the wearing of FOs can be recommended for adults with foot malalignment. However, between study heterogeneity was high for selected outcome parameters (e.g., peak ankle eversion). Therefore, more high-quality research is needed to elucidate the effects of short-term FO application on walking kinematics and kinetics as well as lower limbs muscular activation. Registration number: The protocol for this systematic review with meta-analysis was registered with PROSPERO on November, 17th 2023 (Project: https://www.crd.york.ac.uk/prospero/#myprospero, ID: CRD42023480039).
... Conversely, another large prospective trial investigating the relationship between foot posture and running-related overuse injuries risk in novice runners provided contradicting evidence and demonstrated a reduced risk of running-related overuse injuries in those with pronated foot posture (Nielsen et al., 2014). Furthermore, a small prospective trial reported that motion control footwear (including a medial post, dual-density midsole, and broader sole plate) may actually lead to more runningrelated pain compared to neutral footwear, irrespective of the foot posture index (Ryan et al., 2011). The underlying reasons for these contradictions remain unclear. ...
Footwear science research has seen a roughly 10-fold increase in publications over the last 20 years. This commentary will focus on the three primary research themes of this time frame: methodological developments, running-related injuries, and performance. Within each theme, we summarise the knowledge generated through the substantial increase in publications over the last couple of decades. The methodological developments highlight both improvements in data analysis techniques as well as changes in how we measure variables of interest. Running-related injury prediction paradigms have evolved significantly during these years, which affect how we recommend moving forward in the field. Substantial excitement has filled the performance research field, as we discuss how the advent of Advanced Footwear Technologies altered the research questions and approaches. The undeniable growth in the field over in recent years can be attributed to a strong foundation of knowledge, nurtured by a curiosity to obtain understanding through holistic approaches. The community has embarked on the next stage of the journey, armed with new data collection tools and analytical methodologies, with the objective to better understand the effect of novel footwear design on performance enhancement and injury prevention.
... Assigning shoes based on arch type did not significantly reduce the rate of injuries during 12 weeks of basic training for male or female military recruits (Knapik et al., 2010(Knapik et al., , 2014. Ryan et al. (2011) found that female recreational runners who were randomly assigned motion control shoes incurred more missed days (79 days) due to pain during a 13-week half marathon training program than those assigned a neutral (64 days) or stability (51 days) shoe. Likewise, Nielsen et al. (2014) did not find significant differences in injury risk among 927 novice runners with varying arch types who trained in neutral shoes. ...
Many runners seek health professional advice regarding footwear recommendations to reduce injury risk. Unfortunately, many clinicians, as well as runners, have ideas about how to select running footwear that are not scientifically supported. This is likely because much of the research on running footwear has not been highly accessible outside of the technical footwear research circle. Therefore, the purpose of this narrative review is to update clinical readers on the state of the science for assessing runners and recommending running footwear that facilitate the goals of the runner. We begin with a review of basic footwear construction and the features thought to influence biomechanics relevant to the running medicine practitioner. Subsequently, we review the four main paradigms that have driven footwear design and recommendation with respect to injury risk reduction: Pronation Control, Impact Force Modification, Habitual Joint (Motion) Path, and Comfort Filter. We find that evidence in support of any paradigm is generally limited. In the absence of a clearly supported paradigm, we propose that in general clinicians should recommend footwear that is lightweight, comfortable, and has minimal pronation control technology. We further encourage clinicians to arm themselves with the basic understanding of the known effects of specific footwear features on biomechanics in order to better recommend footwear on a patient-by-patient basis.
... Pronated-foot reported a lower incidence of injury compared to neutral runners. Other studies have concluded on the same results [26,27]. In 2014, Neal et al., realized a systematic review on the relationship between FoP and lower limb injury [7]. ...
Background
Foot pronation is generally linked to musculoskeletal injuries, especially in relation to joint deviation caused by pronation during dynamic activities. However, no consensus appeared in the methodological way to determine foot function, and several tests propose to identify foot pronation under different conditions, from static testing to running. The aim of this study was to determine the level of agreement between different foot function classification measures.
Methods
One hundred and six subjects completed 5-foot function tests at standing position, walking and running. Foot Posture Index (FPI) was undertaken to determine foot function during static posture. The Center of Pressure Excursion Index (CPEI) and 3 Foot Balance tests (FBs) were realized during walking and running trials to assess pronation during dynamic activities. Agreement between the measures was determined using the Cohen’s Kappa coefficient (K) between 2 measures and the Fleiss Kappa (FK) between 3 or more measures.
Results
Overall agreement between the measures reported a fair agreement (Kf = 0.2). Static and walking foot tests determination agreement was moderate (K = 0.5), while agreement between FPI and FBs tests were fair (K < 0.4). Fair results were also reported between walking and running tests (K < 0.4). The concordance between running tests classification was fair (Kf = 0.2).
Conclusions
The lack of agreement between tests confirms the need for a consensus on an appropriate measurement of the foot function. Static foot tests are mainly used to determine foot function during dynamic activities. However, the lack of agreement between tests could question the relevance of the static foot function assessments. The FPI reported a moderate agreement with the walking classification test, but it should be accompanied by a dynamic test in order to limit the risk of misinterpretation.
... Although running places a relatively low equipment burden on a runner-most require little more than shoes, shorts, and a top-pairing the right equipment with the right runner is extremely important, especially when it comes to footwear. Quite simply, the wrong running shoes can sabotage a runner's training by increasing the likelihood of injury (Ryan et al. 2011). Of course recommender systems have a long history when it comes to suggesting clothing to users and by incorporating information about a runner's physical characteristics (sex, weight, age, gait) and their training (weekly volume, pace, terrain, etc.), it should be possible to make highly targeted and appropriate footwear recommendations to optimise training and racing, and reduce the risk of injury or discomfort; see, for example, (Marks 2017;Zrenner et al. 2018;Frejlichowski et al. 2016;Wakita et al. 2015;Hwangbo et al. 2018). ...
Every year millions of people, from all walks of life, spend months training to run a traditional marathon. For some it is about becoming fit enough to complete the gruelling 26.2 mile (42.2 km) distance. For others, it is about improving their fitness, to achieve a new personal-best finish-time. In this paper, we argue that the complexities of training for a marathon, combined with the availability of real-time activity data, provide a unique and worthwhile opportunity for machine learning and for recommender systems techniques to support runners as they train, race, and recover. We present a number of case studies—a mix of original research plus some recent results—to highlight what can be achieved using the type of activity data that is routinely collected by the current generation of mobile fitness apps, smart watches, and wearable sensors.
The purpose of this study was to determine if running biomechanical variables measured by wearable technology were prospectively associated with running injuries in Active Duty Soldiers. A total of 171 Soldiers wore a shoe pod that collected data on running foot strike pattern, step rate, step length and contact time for 6 weeks. Running-related injuries were determined by medical record review 12 months post-study enrollment. Differences in running biomechanics between injured and non-injured runners were compared using independent t-tests or ANCOVA for continuous variables and chi-square analyses for the association of categorical variables. Kaplan-Meier survival curves were used to estimate the time to a running-related injury. Risk factors were carried forward to estimate hazard ratios using Cox proportional hazard regression models. Forty-one participants (24%) sustained a running-related injury. Injured participants had a lower step rate than non-injured participants, but step rate did not have a significant effect on time to injury. Participants with the longest contact time were at a 2.25 times greater risk for a running-related injury; they were also relatively slower, heavier, and older. Concomitant with known demographic risk factors for injury, contact time may be an additional indicator of a running-related injury risk in Active Duty Soldiers.
This work aimed to investigate the association between the perceived cushioning of a set of trail-running shoes with both their mechanical response to the impact test and the acceleration of lower limb segments while running indoors and outdoors. Earlier studies have typically focussed on the effect of road-running shoe cushioning, whereas very few have examined the perception of trail runners and outdoor trail-running conditions. Seven trail runners were trained to become reliable in evaluating the level of cushioning on a scale ranging from 0 to 100 and then asked to rate the cushioning of eight trail-running shoes while running. Shoe specimens were mechanically characterized through an impact test. In addition, the effect on running biomechanics was tested by wearing two accelerometers on the tibia and foot. The in-lab impact test revealed that the perceived cushioning was inversely associated with the force amplitude and directly associated with the impact duration. The running test showed that the median frequency of the tibial acceleration during the first 25% of the stance phase decreases with increasing cushioning during both indoor (p = 0.02, rs = −0.83) and outdoor conditions (p < 0.001, rs = −0.79). In conclusion, the perceived cushioning was quantitatively associated with the outcomes of impact and running tests.
Background:
Lower-limb running injuries are common. Running shoes have been proposed as one means of reducing injury risk. However, there is uncertainty as to how effective running shoes are for the prevention of injury. It is also unclear how the effects of different characteristics of running shoes prevent injury.
Objectives:
To assess the effects (benefits and harms) of running shoes for preventing lower-limb running injuries in adult runners.
Search methods:
We searched the following databases: CENTRAL, MEDLINE, Embase, AMED, CINAHL Plus and SPORTDiscus plus trial registers WHO ICTRP and ClinicalTrials.gov. We also searched additional sources for published and unpublished trials. The date of the search was June 2021.
Selection criteria:
We included randomised controlled trials (RCTs) and quasi-RCTs involving runners or military personnel in basic training that either compared a) a running shoe with a non-running shoe; b) different types of running shoes (minimalist, neutral/cushioned, motion control, stability, soft midsole, hard midsole); or c) footwear recommended and selected on foot posture versus footwear not recommended and not selected on foot posture for preventing lower-limb running injuries. Our primary outcomes were number of people sustaining a lower-limb running injury and number of lower-limb running injuries. Our secondary outcomes were number of runners who failed to return to running or their previous level of running, runner satisfaction with footwear, adverse events other than musculoskeletal injuries, and number of runners requiring hospital admission or surgery, or both, for musculoskeletal injury or adverse event.
Data collection and analysis:
Two review authors independently assessed study eligibility and performed data extraction and risk of bias assessment. The certainty of the included evidence was assessed using GRADE methodology.
Main results:
We included 12 trials in the analysis which included a total of 11,240 participants, in trials that lasted from 6 to 26 weeks and were carried out in North America, Europe, Australia and South Africa. Most of the evidence was low or very low certainty as it was not possible to blind runners to their allocated running shoe, there was variation in the definition of an injury and characteristics of footwear, and there were too few studies for most comparisons. We did not find any trials that compared running shoes with non-running shoes. Neutral/cushioned versus minimalist (5 studies, 766 participants) Neutral/cushioned shoes may make little or no difference to the number of runners sustaining a lower-limb running injuries when compared with minimalist shoes (low-certainty evidence) (risk ratio (RR) 0.77, 95% confidence interval (CI) 0.59 to 1.01). One trial reported that 67% and 92% of runners were satisfied with their neutral/cushioned or minimalist running shoes, respectively (RR 0.73, 95% CI 0.47 to 1.12). Another trial reported mean satisfaction scores ranged from 4.0 to 4.3 in the neutral/ cushioned group and 3.6 to 3.9 in the minimalist running shoe group out of a total of 5. Hence neutral/cushioned running shoes may make little or no difference to runner satisfaction with footwear (low-certainty evidence). Motion control versus neutral / cushioned (2 studies, 421 participants) It is uncertain whether or not motion control shoes reduce the number of runners sustaining a lower-limb running injuries when compared with neutral / cushioned shoes because the quality of the evidence has been assessed as very low certainty (RR 0.92, 95% CI 0.30 to 2.81). Soft midsole versus hard midsole (2 studies, 1095 participants) Soft midsole shoes may make little or no difference to the number of runners sustaining a lower-limb running injuries when compared with hard midsole shoes (low-certainty of evidence) (RR 0.82, 95% CI 0.61 to 1.10). Stability versus neutral / cushioned (1 study, 57 participants) It is uncertain whether or not stability shoes reduce the number of runners sustaining a lower-limb running injuries when compared with neutral/cushioned shoes because the quality of the evidence has been assessed as very low certainty (RR 0.49, 95% CI 0.18 to 1.31). Motion control versus stability (1 study, 56 participants) It is uncertain whether or not motion control shoes reduce the number of runners sustaining a lower-limb running injuries when compared with stability shoes because the quality of the evidence has been assessed as very low certainty (RR 3.47, 95% CI 1.43 to 8.40). Running shoes prescribed and selected on foot posture (3 studies, 7203 participants) There was no evidence that running shoes prescribed based on static foot posture reduced the number of injuries compared with those who received a shoe not prescribed based on foot posture in military recruits (Rate Ratio 1.03, 95% CI 0.94 to 1.13). Subgroup analysis confirmed these findings were consistent between males and females. Therefore, prescribing running shoes and selecting on foot posture probably makes little or no difference to lower-limb running injuries (moderate-certainty evidence). Data were not available for all other review outcomes.
Authors' conclusions:
Most evidence demonstrates no reduction in lower-limb running injuries in adults when comparing different types of running shoes. Overall, the certainty of the evidence determining whether different types of running shoes influence running injury rates was very low to low, and as such we are uncertain as to the true effects of different types of running shoes upon injury rates. There is no evidence that prescribing footwear based on foot type reduces running-related lower-limb injures in adults. The evidence for this comparison was rated as moderate and as such we can have more certainty when interpreting these findings. However, all three trials included in this comparison used military populations and as such the findings may differ in recreational runners. Future researchers should develop a consensus definition of running shoe design to help standardise classification. The definition of a running injury should also be used consistently and confirmed via health practitioners. More researchers should consider a RCT design to increase the evidence in this area. Lastly, future work should look to explore the influence of different types or running shoes upon injury rates in specific subgroups.
Objective: Provide a current review of the literature concerning the epidemiology and risk factors for injuries in runners. Data sources: The information in this paper is taken from a review of articles and book chapters (Source: PubMed and MEDLINE, years covered 1966-2006). Conclusions: Understanding the precise causative nature of risk factors in running populations remains a challenging task. Comparison of various works in the literature is impeded by large variations in injury definition, subject population and study design. Weekly running volume continues to be considered a strong risk factor, however more work is needed to determine whether it is the absolute volume, or the increase in volume that is deleterious. Recent research has provided greater insight into the risks that previous injury and lack of full rehabilitation may play in recreational runners starting a training program. Variables related to excessive rear-foot eversion and pronation are frequently sited in combination with the incidence of specific injuries; however, the role of impact characteristics remains in debate. Isokinetic research of hip muscle function is helping to link our understanding of lower extremity kinematics, but requires more research to be proven as a causative factor. Future research in joint coupling and functional training of the complete lower extremity will be beneficial in implementing preventative interventions for running populations.
The Foot Posture Index (FPI) is a validated method for quantifying standing foot posture, and is being used in a variety of clinical settings. There have however, been no normative data available to date for comparison and reference. This study aimed to establish normative FPI reference values.
Studies reporting FPI data were identified by searching online databases. Nine authors contributed anonymised versions of their original datasets comprising 1648 individual observations. The datasets included information relating to centre, age, gender, pathology (if relevant), FPI scores and body mass index (BMI) where available. FPI total scores were transformed to interval logit scores as per the Rasch model and normal ranges were defined. Comparisons between groups employed t-tests or ANOVA models as appropriate and data were explored descriptively and graphically.
The main analysis based on a normal healthy population (n = 619) confirmed that a slightly pronated foot posture is the normal position at rest (mean back transformed FPI raw score = +4). A 'U' shaped relationship existed for age, with minors and older adults exhibiting significantly higher FPI scores than the general adult population (F = 51.07, p < 0.001). There was no difference between the FPI scores of males and females (2.3 versus 2.5; t = -1.44, p = 0.149). No relationship was found between the FPI and BMI. Systematic differences from the adult normals were confirmed in patients with neurogenic and idiopathic cavus (F = 216.981, p < 0.001), indicating some sensitivity of the instrument to detect a posturally pathological population.
A set of population norms for children, adults and older people have been derived from a large sample. Foot posture is related to age and the presence of pathology, but not influenced by gender or BMI. The normative values identified may assist in classifying foot type for the purpose of research and clinical decision making.
Running is one of the most popular leisure sports activities. Next to its beneficial health effects, negative side effects in terms of sports injuries should also be recognised. Given the limitations of the studies it appears that for the average recreational runner, who is steadily training and who participates in a long distance run every now and then, the overall yearly incidence rate for running injuries varies between 37 and 56%. Depending on the specificity of the group of runners concerned (competitive athletes; average recreational joggers; boys and girls) and on different circumstances these rates vary. If incidence is calculated according to exposure of running time the incidence reported in the literature varies from 2.5 to 12.1 injuries per 1000 hours of running. Most running injuries are lower extremity injuries, with a predominance for the knee. About 50 to 75% of all running injuries appear to be overuse injuries due to the constant repetition of the same movement. Recurrence of running injuries is reported in 20 to 70% of the cases. From the epidemiological studies it can be concluded that running injuries lead to a reduction of training or training cessation in about 30 to 90% of all injuries, about 20 to 70% of all injuries lead to medical consultation or medical treatment and 0 to 5% result in absence from work. Aetiological factors associated with running injuries include previous injury, lack of running experience, running to compete and excessive weekly running distance. The association between running injuries and factors such as warm-up and stretching exercises, body height, malalignment, muscular imbalance, restricted range of motion, running frequency, level of performance, stability of running pattern, shoes and inshoe orthoses and running on 1 side of the road remains unclear or is backed by contradicting or scarce research findings. Significantly not associated with running injuries seem age, gender, body mass index, running hills, running on hard surfaces, participation in other sports, time of the year and time of the day. The prevention of sports injuries should focus on changes of behaviour by health education. Health education on running injuries should primarily focus on the importance of complete rehabilitation and the early recognition of symptoms of overuse, and on the provision of training guidelines.
• A cohort of 1680 runners was enrolled through two community road race events and monitored during a 12-month follow-up period for the occurrence of musculoskeletal injuries. Fortyeight percent of the runners experienced at least one injury, and 54% of these injuries were new; the remainder were recurrences of previous injuries. The risk of injury was associated with increased running mileage but was relatively unassociated with other aspects of training, such as usual pace, usual running surface, hill running, or intense training. Injury rates were equal for all age-sex groups and were independent of years of running experience. Runners injured in the previous year had approximately a 50% higher risk for a new injury during follow-up.(Arch Intern Med. 1989;149:2561-2564)
Using a survey questionnaire design, we investigated the incidence, site, and nature of jogging injuries among all participants of a popular 16 km race. The response rate was 83.6%. Of 4,358 male joggers, 45.8% had sustained jogging injuries during the 1 year study period, 14.2% had required medical care, and 2.3% had missed work because of jogging injuries. Occur rence of jogging injuries was independently associated with higher weekly mileage (P < 0.001), history of previous running injuries (P < 0.001), and competitive training motivation (P = 0.03). Higher mileage was also associated with more frequent medical consultations due entirely to jogging-related injuries. In 33 to 44 year olds (N = 1,757), the number of years of running was inversely related to incidence of injuries (P = 0.02). Injuries were not significantly related to race running speed, training surface, characteristics of running shoes, or relative weight. Achillodynia and calf muscle symptoms were the two most common overuse injuries and occurred significantly more often among older run ners with increased weekly mileage. We conclude that jogging injuries are frequent, that the number of firmly established etiologic factors is low, and that, in recom mending jogging, moderation should be the watchword.
Popular running magazines and running shoe companies suggest that imprints of the bottom of the feet (plantar shape) can be used as an indication of the height of the medial longitudinal foot arch and that this can be used to select individually appropriate types of running shoes. This study examined whether or not this selection technique influenced injury risk during United States Army Basic Combat Training (BCT). After foot examinations, BCT recruits in an experimental group (E: n = 1,079 men and 451 women) selected motion control, stability, or cushioned shoes for plantar shapes judged to represent low, medium, or high foot arches, respectively. A control group (C: n = 1,068 men and 464 women) received a stability shoe regardless of plantar shape. Injuries during BCT were determined from outpatient medical records. Other previously known injury risk factors (e.g., age, fitness, and smoking) were obtained from a questionnaire and existing databases. Multivariate Cox regression controlling for other injury risk factors showed little difference in injury risk between the E and C groups among men (risk ratio (E/C) = 1.01; 95% confidence interval = 0.88-1.16; p = 0.87) or women (risk ratio (E/C) = 1.07; 95% confidence interval = 0.91-1.25; p = 0.44). In practical application, this prospective study demonstrated that selecting shoes based on plantar shape had little influence on injury risk in BCT. Thus, if the goal is injury prevention, this selection technique is not necessary in BCT.
Approximately 36 million Americans participate in running each year, with 10.5 million running at least 100 d x yr(-1). Although running injuries are well understood medically, their potential risk factors are not. Thus, we presently have limited ability to identify individuals at high risk for overuse injuries.
This study aimed to identify behavioral and physiological risk factors that influenced potential knee injury mechanisms, including knee joint forces and knee moments.
Participants included 20 adults ranging in age from 20 to 55 yr (n = 7 males and n = 13 females). During the first screening visit, quadriceps and hamstring flexibility was assessed, and Q-angle, height, and weight were measured. During the second screening visit, participants completed a series of questionnaires and a gait analysis to calculate knee joint loads. An isokinetic dynamometer was used to measure eccentric and concentric knee extension strength.
Body weight (r = 0.48, P = 0.03), weekly mileage (r = 0.62, P = 0.005), and concentric knee extension strength (r=0.68, P = 0.0001) were significantly correlated with tibiofemoral compressive force. Knee extension moment displayed a negative correlation with hamstring flexibility (r = -0.47, P = 0.04). Both weekly mileage (r = 0.50, P = 0.03) and concentric knee extension strength (r = 0.60, P = 0.01) had significant positive correlations with patellofemoral force.
The results of this study relate larger knee joint loads to poor hamstring flexibility, greater body weight, greater weekly mileage, and greater muscular strength. Most of these risk factors could potentially be modified to reduce joint loads to lower the risk of injury.
Running is one of the most popular leisure sports activities. Next to its beneficial health effects, negative side effects in terms of sports injuries should also be recognised. Given the limitations of the studies it appears that for the average recreational runner, who is steadily training and who participates in a long distance run every now and then, the overall yearly incidence rate for running injuries varies between 37 and 56%. Depending on the specificity of the group of runners concerned (competitive athletes; average recreational joggers; boys and girls) and on different circumstances these rates vary. If incidence is calculated according to exposure of running time the incidence reported in the literature varies from 2.5 to 12.1 injuries per 1000 hours of running. Most running injuries are lower extremity injuries, with a predominance for the knee. About 50 to 75% of all running injuries appear to be overuse injuries due to the constant repetition of the same movement. Recurrence of running injuries is reported in 20 to 70% of the cases. From the epidemiological studies it can be concluded that running injuries lead to a reduction of training or training cessation in about 30 to 90% of all injuries, about 20 to 70% of all injuries lead to medical consultation or medical treatment and 0 to 5% result in absence from work. Aetiological factors associated with running injuries include previous injury, lack of running experience, running to compete and excessive weekly running distance. The association between running injuries and factors such as warm-up and stretching exercises, body height, malalignment, muscular imbalance, restricted range of motion, running frequency, level of performance, stability of running pattern, shoes and inshoe orthoses and running on 1 side of the road remains unclear or is backed by contradicting or scarce research findings. Significantly not associated with running injuries seem age, gender, body mass index, running hills, running on hard surfaces, participation in other sports, time of the year and time of the day. The prevention of sports injuries should focus on changes of behaviour by health education. Health education on running injuries should primarily focus on the importance of complete rehabilitation and the early recognition of symptoms of overuse, and on the provision of training guidelines.
Excessive pronation is accepted as a good indicator for various running injuries. The least amount of pronation takes place when running barefoot. The latest investigations show that this is connected to a large torsional movement between forefoot and rearfoot which can be influenced by the shoe sole construction. The shoes which are in use among runners in track and field are basically of two types, running shoes (in general torsionally stiff) and spikes (torsionally flexible). The possibly varying effect of these shoes on the shoe/foot motion in running is not known. The purpose of this investigation was therefore to show whether the pronation angle and the torsion angle differ when running barefoot, with spikes, and with running shoes (forefoot touchdown, N = 9 left and right). A film analysis provided the angular movements of the lower leg, rearfoot, and forefoot as well as pronation and torsion in the frontal plane. The results show that at touchdown the torsional movements with both shoe types are quite different from those of running barefoot. With shoes, the torsion angle is reduced back to zero--with running shoes more than with spikes--and the pronation angle is increased beyond the barefoot values (P less than 0.01). In order to reduce the risk of injury, both shoe types should be improved--the running shoes with respect to torsion and the spikes with respect to pronation.
Visual analogue scales (VAS) have been used in the social and behavioral sciences to measure a variety of subjective phenomena. The VAS method has potential utility for the measurement of a variety of clinical phenomena of interest to nurse investigators. In this review a description of the various forms of the VAS and an historical overview of their development are presented. In addition, conceptual, psychometric, and statistical aspects of the VAS are considered. Finally, strengths and limitations of the VAS method are addressed.