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The Biomechanical and Perceptual Influence of Chain Resistance on the Performance of the Olympic Clean
Abstract
Proponents of chain training suggest that using chains hung from the ends of barbells rather than using conventional barbells alone enhances strength, power, and neuromuscular adaptations. The purpose of this study was to determine whether a conventional barbell with chains compared to a conventional barbell without chains would affect the performance of an Olympic Clean. The subjects were also asked regarding their perception of how chains affected their lifting. Four male and 3 female competitive weightlifters who used chains as part of their training participated in the study. The testing protocol compared the subjects' lifting 80% and 85% of their 1 repetition maximum (1RM) using conventional barbells and their lifting 80% and 85% of their 1RM using chains (75% conventional barbells + 5% chains and 80% conventional barbells + 5% chains, respectively). Video analysis evaluated the bar's vertical displacement and velocity and the rate of force production. Vertical ground reaction forces for the first-pull, unweighting, and second-pull phases of the lift were evaluated by using a force plate. After testing, the subjects completed a 2-item questionnaire asking individual perception of the effects of the chains. The results showed no significant difference for condition for any of the variables examined. In contrast, all subjects perceived that the chains required a greater effort. In conclusion, the results indicated that the addition of chains provided no greater value over lifting conventional barbells alone in the performance of the Olympic Clean, although the subjects perceived the chains to have a positive effect.
... Of these, chains are the easiest to implement in training, by just attaching the chains to the barbell. Several studies have examined the acute effects of attaching chains to the barbell; however, most of these were studies in exercises for the lower body [13][14][15][16][17][18]. To the best of our knowledge, only two studies have examined upper body exercises [19,20]. ...
... In addition, the difference in load from the bottom-to top-matched positions with chains was much higher in the study of Baker and Newton [19] than in the present study (15% vs. 5.1%), which also could influence the lifting velocity. This speculation is supported by previous studies [13,14]. For example, Heelas et al. [14] compared lifting velocity in the deadlift between using only free weights and using free weights combined with a different percentage of variable resistance. ...
... The authors reported that the mean velocity increased as the contribution from the variable resistance was increased. Contrary to this, Berning et al. [13] found no difference in velocity when comparing the Olympic clean and jerk using either free weights or free weights + chains. Importantly, and similar to the present study, the contribution from the chains in Berning et al. [13] was approximately 5%, which the authors suggest may be too little to elicit an effect. ...
The aim of the study was to investigate the acute effects of attaching chains on barbell kinematics and muscle activation in the bench press. Twelve resistance-trained men (height: 1.79 ± 0.05 m, weight: 84.3 ± 13.5 kg, one repetition maximum (1-RM) bench press of 105 ± 17.1 kg) lifted three repetitions of bench press in three conditions: (1) conventional bench press at 85% of 1-RM and bench press with chains that were (2) top-matched and (3) bottom-matched with the resistance from the conventional resistance lift. Barbell kinematics and the muscle activity of eight muscles were measured at different heights during lowering and lifting in the three conditions of the bench press. The main findings were that barbell kinematics were altered using the chains, especially the 85% bottom-matched condition that resulted in lower peak velocities and longer lifting times compared with the conventional 85% condition (p ≤ 0.043). However, muscle activity was mainly only affected during the lowering phase. Based upon the findings, it was concluded that using chains during the bench press alters barbell kinematics, especially when the resistance is matched in the bottom position. Furthermore, muscle activation was only altered during the lowering phase when adding chains to the barbell.
... Additionally, two investigations have utilized VR with descending strength curve exercises. 17,18 This section will discuss methodological disparities between studies measuring acute performance variables, review the training studies that have been conducted comparing VR and TR, and provide a discussion of how VR may be implemented in conjunction with complex training. ...
... In studies measuring performance measures such as force, power, or velocity within an exercise the most notable lack of consistency has been with the load used. Some studies have utilized loads as low as 30% 1RM, 22,60 while others have used loads as high as 85%, 17,18,21,22,25 or a fixed weight. 19,20 It appears that VR is more effective when a greater percent 1RM is used. ...
... Perhaps more importantly than total load, there has been a lack of consistency regarding the amount of resistance coming from variable sources. Some studies have used a standard VR load for each subject, 19,20,23 while others have used a percent of 1RM 17,18,21,22 or percent of the actual load being used for the repetition(s) being tested. 11,13,15,25 If too much or too little resistance is provided by VR, the performance characteristics (e.g. ...
The use of chain or elastic band-resisted variable resistance has become popular in the training of athletes. A number of studies have investigated the utilization of variable resistance vs. traditional resistance training on both acute and chronic performance measures. However, the mechanisms of the observed outcome measures are not fully understood. This review aims to propose a four-part theory regarding the bases by which chain and elastic band-based variable resistance have been shown to be effective. Additionally, it compares methodologies in studies utilizing variable resistance and provides practitioners with recommendations on the use of variable resistance based on the current literature.
... muscle lengthening), the chain links are also lowered onto the floor decreasing the resistance (26). The mass of the chains added is typically substituted for a percentage of the total constant load lifted (5,7,32,34). Baker and Newton (4) proposed that the addition of chains alters the kinetic profile of the strength exercise by allowing an increased duration of acceleration throughout the range of motion and an ability to maintain higher forces towards the end of the movement. A recent meta-analysis by Soria-Gila et al. (31) reported greater strength gains in programmes using chains compared to conventional training, with significant increases observed in both trained and untrained populations where programmes lasted >7 weeks. ...
... In studies examining the addition of 5% chain resistance to 75 and 80% 1RM during the clean and snatch, no difference in bar displacement, bar velocity, ground reaction forces and rate of force development were reported compared to a comparable constant load (7,9). However, the relatively low contribution of the chains might have been insufficient to elicit changes in lifting performance throughout the movement range. ...
... As power is a product of force and velocity, it is plausible the lower force negated the higher velocity, especially given that the relative loadings through the movements are lower with chains. Moreover, it is suggested that untrained participants may show greater improvements with the use of variable resistance training (7). That we found no improvement in peak and mean power may be due to the trained status of our participants. ...
This study sought to determine the effects of variable resistance using chain resistance on bench throw performance. Eight male rugby union players (19.4 ± 2.3 y, 88.8 ± 6.0 kg, 1RM 105.6 ± 17.0 kg) were recruited from a national league team. In a randomised cross-over design participant's performed three bench throws at 45% one repetition maximum (1RM) at a constant load (No Chains) or a variable load (30% 1RM constant load, 15% 1RM variable load; Chains) with seven days between conditions. For each repetition the peak and mean velocity, peak power, peak acceleration and time to peak velocity were recorded. Differences in peak and mean power were very likely trivial and unclear between the Chains and No Chains conditions, respectively. Possibly greater peak and likely greater mean bar velocity were accompanied by likely to most likely greater bar velocity between 50-400 ms from initiation of bench press in the Chains compared to the No Chains condition. Accordingly, bar acceleration was very likely greater in the Chains compared to the No Chains condition. In conclusion, these results show that the inclusion of chain resistance can acutely enhance several variables in the bench press throw and gives support to this type of training.
... It has been suggested that the addition of chains alters the mechanics of traditional resistance exercises to make them more suitable for ERT (5,38). This suggestion is based on the theory that increasing resistance from unfurling chain mass will require the lifter to maintain force production to elevate the barbell to its final position (5,7,8,15). To date, there have been no published reports that have directly examined this theory. ...
... To date, there have been no published reports that have directly examined this theory. Only a limited number of studies have investigated the effects of including chains on the biomechanics of resistance exercises (5,7,8,15). Ebben and Jensen (15) reported that the inclusion of chain resistance had no effect on lift kinetics or electromyographic (EMG) activity during the back squat. ...
... Ebben and Jensen (15) reported that the inclusion of chain resistance had no effect on lift kinetics or electromyographic (EMG) activity during the back squat. Coker and colleagues also failed to report any effects of chains on the kinematics and kinetics of the snatch (8) and clean (7). In contrast, Baker and Newton (5) reported that the inclusion of chains significantly increased mean and peak lifting velocities during the bench press. ...
The purpose of this study was to investigate whether the deadlift could be effectively incorporated with explosive resistance training (ERT) and to investigate whether the inclusion of chains enhanced the suitability of the deadlift for ERT. Twenty-three resistance trained athletes performed the deadlift with 30, 50, and 70% 1-repetition maximum (1RM) loads at submaximal velocity, maximal velocity (MAX), and MAX with the inclusion of 2 chain loads equal to 20 or 40% of the subjects' 1RM. All trials were performed on force platforms with markers attached to the barbell to calculate velocity and acceleration using a motion capture system. Significant increases in force, velocity, power, rate of force development, and length of the acceleration phase (p < 0.05) were obtained when repetition velocity increased from submaximal to maximal. During MAX repetitions with a constant resistance, the mean length of the acceleration phase ranged from 73.2 (±7.2%) to 84.9 (±12.2%) of the overall movement. Compared to using a constant resistance, the inclusion of chains enabled greater force to be maintained to the end of the concentric action and significantly increased peak force and impulse (p < 0.05), while concurrently decreasing velocity, power, and rate of force development (p < 0.05). The effects of chains were influenced by the magnitude of the chain and barbell resistance, with greater increases and decreases in mechanical variables obtained when heavier chain and barbell loads were used. The results of the investigation suggest that the deadlift can be incorporated effectively in ERT programs. Coaches and athletes should be aware that the inclusion of heavy chains may have both positive and negative effects on kinematics and kinetics of an exercise.
... Athletes involved in strength and power sports such as jumping, sprinting, and throwing frequently use Olympic lifting exercises, such as the power clean, due to their effectiveness in increasing kinetic variables such as peak ground reaction force (PGRF), power output (PO), and rate of force development (RFD) (14)(15)(16)(17)(18). The technical aspects of the Olympic lifts are very demanding and require a great deal of mobility and co-ordination from a number of joints (18,19). ...
... Non-significant increases were found at 50% 1RM (5% BM = 4.3%, 12% BM = 5.5%) and 70% 1RM (3.4% both conditions) efforts compared to the TR condition. These findings are in agreement with Berning et al. (14) and Coker et al. (15) who demonstrated non-significant changes in vertical GRF for the first pull, second pull, and un-weighting phase during the power clean and snatch exercises performed at 80% and 85% of 1RM with the inclusion of chains. As was found with chains, it would seem that the additional load via WR provides similar PGRFs to traditional loading methods. ...
Loading of 5% or 12% body mass redistributed from the bar to the body using wearable resistance may positively influence power clean performance due to increased power output and ground reaction forces in recreationally trained young males.
... Subjects were recruited from the student population at the university. Data was combined for males and females, which has been done in previous maximal strength research [25][26][27][28]. Preliminary analysis of the TBP and CGBP also indicated similar patterns of lift mechanics for each exercise between genders. ...
... Data for men and women were combined to increase the statistical power of this study. Even though this approach has been used in previous research investigating strength exercises [25][26][27][28], this could be problematic given the established strength differences that generally exist between men and women [51,52]. Future studies should analyze whether there are gender-specific responses to a 1RM CGBP. ...
The close-grip bench press (CGBP) is a variation of the traditional bench press (TBP) that uses a narrower grip (~95% of biacromial distance (BAD)) and has potential application for athletes performing explosive arm actions from positions where the hands are held close to the torso. Limited research has investigated CGBP mechanics compared to the TBP. Twenty-seven resistance-trained individuals completed a one-repetition maximum TBP and CGBP. The TBP was performed with the preferred grip; the CGBP with a grip width of 95% BAD. A linear position transducer measured lift distance and duration; peak and mean power, velocity, and force; distance and time when peak power occurred; and work. Pre-sticking region (PrSR), sticking region, and post-sticking region distance and duration for each lift was measured. A repeated measures ANOVA was used to derive differences between TBP and CGBP mechanics (p < 0.01); effect sizes (d) were also calculated. A greater load was lifted in the TBP, thus mean force was greater (d = 0.16–0.17). Peak power and velocity were higher in the CGBP, which had a longer PrSR distance (d = 0.49–1.32). The CGBP could emphasize power for athletes that initiate explosive upper-body actions with the hands positioned close to the torso.
... During a variable intra-repetition stimulus weight lifting protocol, a load increase takes place as the barbell is moved through the concentric phase of the range of motion, making it increasingly more difficult to maintain a high velocity and acceleration (11,13,19,48). When using elastic bands, sufficient acceleration is needed in the early lifting stage to overcome elastic recoil and complete the movement (19). ...
... A further characteristic feature of varying resistance is that, besides increasing velocity, it increases the eccentric stimulus of training, and thus the strength needed to slow down or stop the load at the end of the eccentric phase, inducing greater myoelectric activity in the muscles (15). Researchers examining VRT using chains have also reported that this type of training induces stimulus variations, as a consequence of the oscillations that chains produce, which provoke better coordination between agonist, synergistic and stabilizing muscles to control the load (11,31). Several studies (2,21,48) have detected improvements in muscular strength and power generated in bench press and squat exercises in response to elastic plus free-weight loaded training, compared to similar training in the absence of elastic resistance. ...
Variable resistance training (VRT) methods improve the rate of force development (RFD), coordination between antagonist and synergist muscles, the recruitment of motor units, and reduce the drop in force produced in the sticking region. However, the beneficial effects of long-term VRT on maximal strength both in athletes and untrained individuals have been much disputed. The purpose of this study was to compare in a meta-analysis the effects of a long-term (>= 7 weeks) VRT program using chains or elastic bands and a similar constant resistance program in both trained adults practicing different sports and untrained individuals. Intervention effect sizes were compared among investigations meeting our selection and inclusion criteria using a random effects model. The published studies considered were those addressing VRT effects on the one repetition maximum (1RM). Seven studies involving 235 subjects fulfilled the selection and inclusion criteria. VRT led to a significantly greater mean strength gain (weighted mean difference: 5.03 kg; 95% CI: 2.26-7.80 kg; Z = 3.55; P < 0.001) than the gain recorded in response to conventional weight training. Long-term VRT training using chains or elastic bands attached to the barbell emerged as an effective evidence-based method of improving maximal strength both in athletes with different sports backgrounds and untrained subjects.
... The term accommodating resistance refers to purposeful modifications of the effective load experienced in an exercise throughout a repetition [19,[89][90][91][92]. This technique is most often used in training by powerlifters [69] but also by other types of athletes in general strength and conditioning work [89,91,93]. ...
... The term accommodating resistance refers to purposeful modifications of the effective load experienced in an exercise throughout a repetition [19,[89][90][91][92]. This technique is most often used in training by powerlifters [69] but also by other types of athletes in general strength and conditioning work [89,91,93]. One popular method of introducing accommodating resistance involves the fixing of an elastic band between the load (such as a barbell) and floor (or other fixed object, e.g. the power cage or the frame of a resistance machine). ...
In the context of resistance training the so-called "sticking point" is commonly understood as the position in a lift in which a disproportionately large increase in the difficulty to continue the lift is experienced. If the lift is taken to the point of momentary muscular failure, the sticking point is usually where the failure occurs. Hence the sticking point is associated with an increased chance of exercise form deterioration or breakdown. Understanding the mechanisms that lead to the occurrence of sticking points as well as different training strategies that can be used to overcome them is important to strength practitioners (trainees and coaches alike) and instrumental for the avoidance of injury and continued progress. In this article we survey and consolidate the body of existing research on the topic: we discuss different definitions of the sticking point adopted in the literature and propose a more precise definition, describe different muscular and biomechanical aspects that give rise to sticking points, and review the effectiveness of different training modalities used to address them.
... Neste contexto, um dos meios conhecidos para se proporcionar a RV é o treino de força com uso de correntes (chain resistance training [CRT]. (BAKER;NEWTON, 2009;COOKER;BRIGGS, 2008). Nele, correntes são adicionadas para compensar a facilidade de execução no final do movimento e minimizar os efeitos do PFM. ...
... Em relação à eficiência do CRT, pelo menos dois estudos indicaram que exercícios realizados com este método tendem a aumentar a percepção subjetiva de esforço durante os treinos, mesmo com atletas treinados em levantamento de peso olímpico. BRIGGS, 2008;BRIGGS, 2006). E, recentemente, observou-se que esta estratégia também é adequada para o aumento da força no supino reto entre atletas de voleibol e basquetebol. ...
The Post-Activation Potentiation (PAP) is a strategy to improve performance, using a fixed load (RF), defined at the sticking point (PFM). Moreover, the use of chains (CRT) is an effort with variable resistance (RV). Thus, the objective was to evaluate the effects of CRT in the countermovement jump (CMJ). With an intervention study, 15 subjects were evaluated for the maximum squat load (1RM) and height in CMJ. After that, they performed three types of interventions: i) RF with 85% of 1RM; ii) RV with 85% of 1RM positioned in PFM (RV-TF), and iii) RV at 85% of 1RM positioned at greater knee extension (RV-TV). It was observed increase in CMJ to RV-TF and RV-TV, but not to RF. It is concluded that there was PPA with the two RV stimulus.
... In their study, the researchers added 20% and 35% of 85% of subjects' 1RM. Several studies (5,6) have investigated the velocity of a barbell and vertical ground reaction force when subjects performed clean and snatch lift with chains added to the barbell. The results of these studies show no significant differences between the bar's velocity and vertical ground reaction with the addition of chains to a barbell and the barbell alone. ...
... In the current study, the percentage changes revealed that the PV decreased from NT to T20 (8.22%). Furthermore, the percentage changes in Stevenson et al. (26) (between the no-band and with-band conditions) and Berning et al. (5) in which the load was established at 85% of 1RM (between the no-chains and with-chains conditions) decreased to 3.76% and 2.99%, respectively. In Coker et al. (6) (at 80% of 1RM), the PV decreased by 4.23% from the no-chains condition to the with-chains condition. ...
Elastic tubing attached to a barbell has been reported to enhance strength and power to a greater extent as compared to conventional barbells. The aim of this study was to investigate the effect of the additional elastic tubing to a barbell during a clean pull on peak power (PP), peak velocity (PV), and peak force (PF). Six competitive female weightlifters (Mean age = 16.7 ± 2.1 years) performed 3 sets of 3 repetitions of the clean pull at 90% of 1 repetition maximum (1RM). Testing was conducted on three separate days: day one without elastic tubing (NT) and the other two days with two elastic tubing loading conditions (T10 and T20), in random order. No Tubing (NT) represents a condition where all resistance was acquired from the barbell (90% of 1RM). T10 and T20 represent conditions of combining elastic tubing at 10% and 20% of the subjects' 90% 1RM with a barbell (90% of 1RM). One-way repeated measures analysis of variance (ANOVA) was used to assess loading conditions on PP, PV, and PF. The results showed that there was a significant increase in all variables-PP, PF, and PV-between T10 and NT and between T20 and NT (p < 0.05). The results reveal that adding a 10% increment to 90% of 1RM appears to be the optimal training condition for increasing power, force, and velocity during the clean pull.
... Neste contexto, um dos meios conhecidos para se proporcionar a RV é o treino de força com uso de correntes (chain resistance training [CRT]. (BAKER;NEWTON, 2009;COOKER;BRIGGS, 2008). Nele, correntes são adicionadas para compensar a facilidade de execução no final do movimento e minimizar os efeitos do PFM. ...
... Em relação à eficiência do CRT, pelo menos dois estudos indicaram que exercícios realizados com este método tendem a aumentar a percepção subjetiva de esforço durante os treinos, mesmo com atletas treinados em levantamento de peso olímpico. BRIGGS, 2008;BRIGGS, 2006). E, recentemente, observou-se que esta estratégia também é adequada para o aumento da força no supino reto entre atletas de voleibol e basquetebol. ...
Este estudo teve por objetivo avaliar os efeitos do treinamento com resistência variável, com uso de correntes, na potencialização pós-ativação (PPA). A partir de estudo de medidas repetidas, oito adultos jovens foram recrutados. Em três dias de intervenções diferentes, cada indivíduo realizou série de cinco agachamentos com 85% de 1RM com resistência invariável ou com resistências variáveis. Altura no salto vertical e tempo de vôo nos saltos com contramovimento foram considerados como variáveis dependentes. Os resultados mostram ausência de PPA no uso de carga invariável e efeitos positivos (p<0,05) do uso de correntes em todas as variáreis analisadas. O uso de correntes parece ser alternativa viável quando se objetiva melhor rendimento em exercício específico de potência muscular, como o salto vertical.
... INTRODUCTION P rogressive resistance exercise can be performed in properly designed weight training programs using different modes of resistance. Although constant external loading is the most popular mode of resistance training (i.e., free weights and pulley systems), variable resistance has lately gained much attention and has become common in commercial gyms, high schools, and collegiate strength and conditioning programs (3,4,6). Variable resistance is designed to change the external resistance load throughout an exercise's range of motion (i.e., elastic bands, bands and/or chains attached to the ends of bars) (12). ...
... The perception of effort did not change in the ER + PC approach, in comparison with the conventional PC mode. Previous studies observed that subjects perceive a greater effort during Olympic lifting exercises when combining variable resistance (chains) to FWR in comparison to conventional approach (3,4). Differences related to type of variable resistance ''in series'' ER vs. chains attached to the barbell, the exercise analyzed (biceps curl on PC vs. Olympic clean) and the tool selected to measure perceptual response (OMNI-RES vs. open-answer questionnaire) could explain this disparity of results concerning perceived exertion. ...
This study aimed to investigate the role of elastic resistance (ER) applied "in series" to a pulley-cable (PC) machine on the number of repetitions performed, kinematics parameters, and perceived exertion during a biceps-curl set to failure with a submaximal load (70% of the 1 repetition maximum). Twenty-one undergraduate students (17 men and 4 women) performed, on 2 different days, 1 biceps-curl set on the PC machine. Subjects were randomly assigned to complete 2 experimental conditions in a cross-over fashion: conventional PC mode or ER + PC mode. Results indicate ER applied "in series" to a PC machine significantly reduces (p < 0.05) the maximal number of repetitions and results in a smooth and consistent decline in mean acceleration throughout the set, in comparison to the conventional PC mode. Although no significant differences were found concerning intrarepetition kinematics, the ER trended to reduce (18.6%) the peak acceleration of the load. With a more uniformly distributed external resistance, a greater average muscle tension could have been achieved throughout the range of movement, leading to greater fatigue that could explain the lower number of maximal repetitions achieved. The application of force in a smooth, consistent fashion during each repetition of an exercise, while avoiding active deceleration, is expected to enhance the benefits of the resistance exercise, especially for those seeking greater increases in muscular hypertrophy.
... The resistance provided by SLS chains is gravity dependent and determined by the type of steel, density, diameter, and length of the chain used. Two previous studies have calculated length to weight ratios for various sized (diameter) chains assuming that each link was of the same weight; therefore, linear increases in resistance would occur over changing displacement (1,5). ...
... Rubberbased resistance bands have also been used in rotator cuff rehabilitation, assisted and resisted sprint training, and powerlifting training to help athletes overcome the sticking region (8,11,16,19,21,23). Standard link steel chains have been used for the clean and snatch in an attempt to improve explosiveness, but there is little empirical evidence to support such a contention (5)(6)(7). The use of RBR and SLS chains has also been reported to increase activation of stabilizing muscles and enhance neurological adaptations, but there is a lack of scientific proof to support these claims (6,7). ...
Rubber-based resistance (RBR) bands and standard link steel (SLS) chains are 2 forms of variable resistance used throughout the strength and conditioning and rehabilitation communities. The purpose of this study was to quantify the tension of RBR bands and the mass of SLS chains as a function of displacement (increasing in 10-cm increments). Five sets of RBR bands (14-, 22-, 30-, 48-, and 67-mm widths) and 5 sets of SLS chains (6-, 8-, 10-, 13-, 16-mm diameters) were measured using a load cell and a force plate. The RBR bands exhibited curvilinear tension-deformation relationships and were best represented (R >or= 0.99) by second-order polynomial functions, whereas the SLS chains exhibited linear mass-displacement relationships and were best represented (R = 1) by first-order polynomial functions. There were no significant differences (p > 0.05) in force outputs between the load cell and the force plate testing, although the strain gauge is a relatively cheap and viable method of quantifying the variable resistance of chains and bands. The strength and conditioning practitioner when purchasing bands needs to be aware of resting length differences (3.5-5.2%), which resulted in mean tension imbalances of 8-19% in the same color band. This study provides the strength and conditioning coach and clinician with a methodology to quantify variable resistance, which may be useful in the prescription of specific loading intensities.
... Nervous adaptation is the basis of sports performance, and increasing neural drive is very important for exerting muscle strength and explosive force (Aagaard et al., 2002). At the same time, a higher proportion of VR also means that the instability of training becomes greater, which can induce greater involvement of relevant stabilizing muscles and create favourable conditions for the active muscles to exert force, thus facilitating the improvement of intermuscular coordination (Berning et al., 2008). Anderson and Behm (2004) also found that although there are no significant differences in overall EMG activity between the stable and unstable protocols, resistance training on an unstable surface may still force limb musculature to play a greater role in joint stability. ...
The purpose of this study was to explore the effects of the chain squat training (CST) with different chain load ratio (0, 10%, 20% and 30%) on the explosive power of the lower limbs of adolescent male basketball players. Forty-four youth basketball players (age 15.48 ± 0.81 years, body mass 78.86 ± 12.04 kg, height 184.95 ± 6.71 cm) were randomly allocated to one of the four groups: traditional squat training (TST), 10% chains squat training (10% CST), 20% chains squat training (20% CST), and 30% chains squat training (30% CST). Training interventions were performed 2 times per week for 6 weeks, and at the week before (Pre) and after (Post) the 6-week CST program with different chain load ratio, the no-step vertical jump, standing long jump, 15 m shuttle run, 1 R M squat and 30 m sprint test were performed. A 4 (group) × 2 (time) repeated measures analysis of variances (ANOVA) was calculated to show the scatter of each variable, and the Bonferroni’s post-hoc test was used for multiple comparisons, in addition the partial eta-squared (η ² ) was calculated as an estimate of the ES. Significant time × group interaction was noticed for the no-step vertical jump ( p < 0.001; η ² = 0.611), standing long jump ( p < 0.001; η ² = 0.490) and 1 R M squat ( p < 0.01; η ² = 0.333) indicating that better improvements appear in CST compared to TST. However, significant time × group interaction was noted for 15 m shuttle run ( p < 0.001; η ² = 0.428), in favor of TST compared to CST. In addition, the improvements in 30 m sprint were similar between all groups. In conclusion, CST with more chain load has better training effects on lower limb explosive strength and maximum strength, based on the improvement in 1 R M squat and jumping performance. Besides, compared with TST, CST with more chain load might not help to develop better velocity adaptation at higher range of movement.
... Similarly, Kampanart, Chaninchai & Chaipat (2016) reported no difference in the peak power between clean pulls when using VRT with 18%1-RM variable resistance and CRT. Because of the limited number of studies using ballistic movements (Berning, Coker & Briggs, 2008;Coker, Berning & Briggs, 2006;Godwin, Fernandes & Twist, 2018;Kampanart, Chaninchai & Chaipat, 2016), future research in this area is required before a valid conclusion can be drawn. ...
Objective:
Acute effects of variable resistance training (VRT) and constant resistance training (CRT) on neuromuscular performance are still equivocal. We aimed to determine the differences between VRT and CRT in terms of force, velocity, and power outcomes.
Methods:
We searched PubMed, Web of Science, and SPORTDiscus electronic databases for articles until June 2021. Crossover design studies comparing force, velocity, and power outcomes while performing VRT and CRT were included. Two reviewers independently applied the modified version of the Cochrane Collaboration's tool to assess the risk of bias. A three-level random effects meta-analyses and meta-regressions were used to compute standardized mean differences (SMDs) and 95% confidence intervals.
Results:
We included 16 studies with 207 participants in the quantitative synthesis. Based on the pooled results, VRT generated greater mean velocity (SMD = 0.675; moderate Grading of Recommendations Assessment, Development and Evaluation (GRADE) quality evidence) and mean power (SMD = 1.022; low) than CRT. Subgroup analyses revealed that VRT considerably increased the mean velocity (SMD = 0.903; moderate) and mean power (SMD = 1.456; moderate) in the equated loading scheme and the mean velocity (SMD = 0.712; low) in the CRT higher loading scheme. However, VRT marginally significantly reduced peak velocity (SMD = -0.481; low) in the VRT higher loading scheme. Based on the meta-regression analysis, it was found that mean power (p = 0.014-0.043) was positively moderated by the contribution of variable resistance and peak velocity (p = 0.018) and peak power (p = 0.001-0.004) and RFD (p = 0.003) were positively moderated by variable resistance equipment, favoring elastic bands.
Conclusions:
VRT provides practitioners with the means of emphasizing specific force, velocity, and power outcomes. Different strategies should be considered in context of an individual's needs. Systematic review registration: PROSPERO CRD42021259205.
... Finally, there were 35 articles relevant to our study. The remaining 35 articles were further evaluated, and 21 were screened out for the following reasons: 3 studies did not report average or standard deviations [17,40,41]; 1 study did not report maximum-strength indicators [42]; 15 studies did not compare the effects before and after the training intervention [15,20,21,25,[43][44][45][46][47][48][49][50][51][52][53]; 2 studies had no CRT group [54,55]. Finally, a total of 14 studies were included in the meta-analysis. ...
Greater muscular strength is generally associated with superior sports performance, for example, in jumping, sprinting, and throwing. This meta-analysis aims to compare the effects of variable-resistance training (VRT) and constant-resistance training (CRT) on the maximum strength of trained and untrained subjects. PubMed, Web of Science, and Google Scholar were comprehensively searched to identify relevant studies published up to January 2022. Fourteen studies that met the inclusion criteria were used for the systematic review and meta-analysis. Data regarding training status, training modality, and type of outcome measure were extracted for the analyses. The Cochrane Collaboration tool was used to assess the risk of bias. The pooled outcome showed improved maximum strength with VRT, which was significantly higher than that with CRT (ES = 0.80; 95% CI: 0.42–1.19) for all the subjects. In addition, trained subjects experienced greater maximum-strength improvements with VRT than with CRT (ES = 0.57; 95% CI: 0.22–0.93). Based on subgroup analyses, maximum-strength improvement with a VRT load of ≥80% of 1 repetition maximum (1RM) was significantly higher than that with CRT (ES = 0.76; 95% CI: 0.37–1.16) in trained subjects, while no significant differences were found between VRT and CRT for maximum-strength improvement when the load was
... In addition to the element that causes IRVR, different percentages of IRVR have been used to evaluate it. Previous studies have analyzed IRVR percentages of 5% (Berning et al., 2008;Coker et al., 2006), 10% (Ebben & Jensen, 2002) 20% (Stevenson et al., 2010;Swinton et al., 2011;Wallace et al., 2006), 35% (Galpin et al., 2015;Mina et al., 2014;Wallace et al., 2006) and even, unspecified percentages (Cronin et al., 2003;Newton et al., 2002;Saeterbakken et al., 2016). Consequently, we consider the main error is comparing the variable method with a similar load to the CR methods when the load will only be similar in the maximum extension between both methods. ...
Background: In line with the recommendations for sustainable development, SDG 3 highlights the importance of working on health and well-being. In this respect, strength training has proven to be highly effective. Improved physical performance in most sports is associated with increased maximum dynamic strength. The existing literature on strength training methods is extensive, varied and has a certain tradition in the scientific field. Therefore, the regulation and optimal treatment of the load/stimulus with which one works in the development of strength is a key point. The analysis and study of the variability in loads or training stimuli is essential since it is modified according to the objective of the training and adapted to the circumstances. The aim of this study was to compare the differences measured in average and maximum strength, rate of force development (RFD) and the perception of effort (RPE) between two training methods (constant resistance (CR) vs. intra-repetition variable resistance (IRVR) in a bench press. Methods: Due to the methodological difficulties involved in generating an IRVR, fifteen men executed different percentages of one maximum repetition (40%, 60%, 80% and 100%) with CR and IRVR. The percentage to graduate the selected load was 20% of variable resistance. An intra-subject design was used to compare the acute differences between intra-repetition variable resistance and constant resistance. Results: The results showed significant differences in IRVR for maximum force at 1RM (p = 0.001). A significant decrease in RPE with IRVR was documented for all percentages evaluated (p = 0.011). Less accumulated load during execution with IRVR in the first phases of the range of motion (ROM), provides a greater acceleration of the external load, consequently, in the last phase of the concentric extension a faster speed is produced compared to the traditional method with CR (p = 0.036). Conclusion: IRVR method requires a lower load accumulated in the first phase of the ROM allows more acceleration of the external load and therefore overcome the sticking point with a higher velocity. The constant adaptations in the pattern of strength production during the ROM cause the muscles to stay closer to their best "length-tension" ratio in the concentric phase; therefore, they can generate higher levels of strength. In addition, the results obtained show that the IRVR method requires less perceived effort. For all these reasons, it should be considered an effective method for developing maximum dynamic force, mainly for sub-maximum and maximum loads.
... Subjects were recruited from the student population at the university. Data were combined for males and females, which has been done in previous strength testing research [12,[25][26][27]. This approach to this study was a within-subject analysis, and not any comparisons between the sexes, so this approach was deemed appropriate. ...
The close-grip bench press (CGBP) is a variation of the traditional bench press (TBP) that uses a narrower grip (~95% biacromial distance) and has application for athletes performing explosive arm actions where the hands are positioned close to the torso. Limited research has investigated CGBP peak power. Twenty-six strength-trained individuals completed a one-repetition maximum TBP and CGBP. During two other sessions, subjects completed two repetitions as explosively as possible with loads from 20% to 90% for each exercise, with peak power measured by a linear position transducer. A factorial ANOVA calculated between-and within-exercise differences in peak power. Partial correlations controlling for sex determined relationships between absolute and relative strength and peak power load. Peak power for the TBP occurred at 50% 1RM, and 30% 1RM for the CGBP. There were no significant (p = 0.680) differences between peak power at each load when comparing the TBP and CGBP. For the within-exercise analysis, there were generally no significant differences in TBP and CGBP peak power for the 20-50% 1RM loads. There were no significant relationships between strength and peak power load (p = 0.100-0.587). A peak power loading range of 20-50% 1RM for the TBP and CGBP is suggested for strength-trained individuals.
... Subjects were recruited from the student population at the university. Data was combined for males and females, which has been done in previous maximal strength research (3,7,41). Preliminary analysis of the CD and HHBD also indicated similar patterns of lift mechanics within each exercise between the sexes. ...
The high-handle hexagonal bar deadlift (HHBD), a variation of the conventional deadlift (CD), is said to reduce the lift range of motion, which may change the mechanics of the lift. However, no research has investigated this. This study compared the mechanics between a one-repetition maximum (1RM) CD and HHBD. Thirty-one strength-trained subjects (21 males, 10 females) completed a 1RM CD and HHBD. A linear position transducer measured lift distance, duration, and work; and peak and mean power, velocity, and force. The presence of a sticking region (SR) was determined for each lift. A repeated measures ANOVA calculated differences between 1RM CD and HHBD mechanics. A one-way ANOVA compared the mechanics of each lift between subjects who exhibited a SR or not, and the SR between the CD and HHBD. Significance was set at p < 0.01. Subjects lifted a greater load in the HHBD (154.50 ± 45.29 kg) compared to the CD (134.72 ± 40.63 kg). Lift distance and duration were 22% and 25% shorter during the 1RM HHBD, respectively. The HHBD featured greater peak power and velocity, and peak and mean force; more work was done in the CD. Most subjects did not exhibit a CD (68%) or HHBD (77%) SR. There were no differences in CD or HHBD mechanics between subjects with or without a SR, and no differences in SR region distance or duration between the CD and HHBD. Greater force can be generated in the HHBD, which could have implications for strength training adaptations over time.
... Ebben and Jensen (2002) found that the inclusion of chains set at 10% of the total load during a back squat exercise had no significant effect on force production or muscle electromyogram (EMG) activity when compared to a traditional free-weight resistance (FWR). Similarly, Coker, Berning, and Briggs (2006) found no significant difference in movement velocity or the rate and magnitude of ground reaction force application during the snatch or clean exercises (Berning, Coker, & Briggs, 2008) with only 5% resistance imposed via chains. In contrast, Baker and Newton (2009) reported significantly greater mean and peak lifting velocities during a bench press exercise with chain-loaded resistance (CLR) set at 12-16% 1-RM compared to FWR alone. ...
The acute influence of chain-loaded variable resistance exercise on subsequent free-weight one-repetition maximum (1-RM) back squat performance was examined in 16 recreationally active men. The participants performed either a free-weight resistance (FWR) or chain-loaded resistance (CLR) back squat warm-up at 85% 1-RM on two separate occasions. After a 5-min rest, the participants attempted a free-weight 1-RM back squat; if successful, subsequent 5% load additions were made until participants failed to complete the lift. During the 1-RM trials, 3D knee joint kinematics and knee extensor and flexor electromyograms (EMG) were recorded simultaneously. Significantly greater 1-RM (6.2 ± 5.0%; p < .01) and mean eccentric knee extensor EMG (32.2 ± 6.7%; p < .01) were found after the CLR warm-up compared to the FWR condition. However, no difference (p > .05) was found in concentric EMG, eccentric or concentric knee angular velocity, or peak knee flexion angle. Performing a CLR warm-up enhanced subsequent free-weight 1-RM performance without changes in knee flexion angle or eccentric and concentric knee angular velocities; thus a real 1-RM increase was achieved as the mechanics of the lift were not altered. These results are indicative of a potentiating effect of CLR in a warm-up, which may benefit athletes in tasks where high-level strength is required.
... Ebben and Jensen (2002) found that the inclusion of chains set at 10% of the total load during a back squat exercise had no significant effect on force production or muscle electromyogram (EMG) activity when compared to a traditional free-weight resistance (FWR). Similarly, Coker, Berning, and Briggs (2006) found no significant difference in movement velocity or the rate and magnitude of ground reaction force application during the snatch or clean exercises (Berning, Coker, & Briggs, 2008) with only 5% resistance imposed via chains. In contrast, Baker and Newton (2009) reported significantly greater mean and peak lifting velocities during a bench press exercise with chain-loaded resistance (CLR) set at 12-16% 1-RM compared to FWR alone. ...
Introduction
Utilising variable resistance using elastic bands (EB) or chains (Ch) in combination with free-weight resistance (FWR) can be used to manipulate the loading characteristics of a squat lift to increase the range of motion during the lift where substantial loading is applied, while maintaining the average load but mitigating the movement’s ‘sticking point’. The manipulation of the loading characteristics can enable the athlete to operate at near maximal levels for a greater proportion of the exercise, providing a greater stimulus and thus may be a more effective training tool. The aim of the present study was to examine the biomechanical differences of EB, Ch and FWR during submaximal squat exercise.
Methods
Fifteen recreationally active men (age = 26.9 ± 7.9 yr, height = 172.3 ± 18.8 m, mass = 80.6 ± 12.2 kg) experienced in squatting (>3yr) volunteered for the study after giving written informed consent; ethical approval was granted from the University of Northampton. On three separate occasions the subjects performed FWR (control), EB or Ch (variable resistance) squat lifts consisting of two sets of three repetitions at 85% 1-RM (35% of the load was generated from variable resistance). During squatting, 3D motion analysis recorded knee joint kinematics, with vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF) and semitendinosus (ST) electromyograms (EMG) simultaneously recorded. To reduce EMG variability limiting the capacity to detect significant differences, VL, VM, RF EMG data were averaged to represent quadriceps femoris (QF) EMG activity. Repeated measures MANOVA’s were used to examine EMG and kinematic differences between conditions; significance accepted at p < 0.05.
Results
No significant difference (p > 0.05) in peak (1.8-2.8%) and mean eccentric (2.4-6.6%) and peak (3.5-4.0%) and mean concentric (5.0-6.0%) QF EMG activity was found between conditions. Similarly, no difference (p > 0.05) in peak (5.8-14.3%) and mean (9.2-15.8%) eccentric and peak (8.9-9.6%) and mean concentric (1.2-1.7%) knee angular velocities, or peak knee flexion angle (1-1.5%) occurred.
Discussion
Performing the back squat exercise with the use of elastic bands or chains to provide 35% of the resistance compared to FWR alone at 85% of 1-RM did not alter knee extensor EMG amplitude or knee kinematics of the squat lift in either eccentric or concentric phases, or the squat depth achieved. Significant and non-significant changes in kinematics, ground reaction forces and muscle activity are commonly reported in the literature, although substantial differences in methodology likely explain these equivocal findings.
Contact
m.mina@derby.ac.uk
... Ebben and Jensen (2002) found that the inclusion of chains set at 10% of the total load during a back squat exercise had no significant effect on force production or muscle electromyogram (EMG) activity when compared to a traditional free-weight resistance (FWR). Similarly, Coker, Berning, and Briggs (2006) found no significant difference in movement velocity or the rate and magnitude of ground reaction force application during the snatch or clean exercises (Berning, Coker, & Briggs, 2008) with only 5% resistance imposed via chains. In contrast, Baker and Newton (2009) reported significantly greater mean and peak lifting velocities during a bench press exercise with chain-loaded resistance (CLR) set at 12-16% 1-RM compared to FWR alone. ...
Introduction
Varying the load during a back squat exercise using chains in combination with free-weight resistance (FWR) will manipulate the loading characteristics of the lift. Consequently, this may alter neuromuscular demand and induce post-activation potentiation (PAP). Preconditioning the muscle using near maximal or maximal voluntary contractions can increase force production and improve subsequent strength performance, however the influence of chain-loaded resistance (CLR) on subsequent free-weight squat performance has not been examined. Thus, the aim of the present study was to determine the effects of a chain-loaded resistance warm-up routine on subsequent free-weight squat performance.
Methods
Sixteen recreationally active men (age = 26.0 ± 7.8 yr, height = 1.7 ± 0.2 m, mass = 82.6 ± 12.7 kg) experienced in squatting (>3yr) volunteered for the study after giving written informed consent; ethical approval was granted from the University of Northampton. On two separate occasions the subjects performed either a FWR (control) or CLR (experimental) warm-up consisting of two sets of three repetitions of squat lifts at 85% 1-RM (35% of the load generated from CLR). After 5-min rest, subjects performed a free-weight resistance 1-RM squat; when successful a 5% load was added until subjects failed to complete the 1-RM. During the 1-RM, 3D motion analysis recorded knee joint kinematics, with vastus medialis (VM), vastus lateralis (VL), rectus femoris (RF) and semitendinosus (ST) electromyograms (EMG) simultaneously recorded. Repeated measures MANOVA’s were used to examine EMG and kinematic differences between conditions; significance accepted at p<0.05.
Results
A significant increase in 1-RM (6.2%; p<0.01) and mean eccentric VM EMG (32%; p<0.05) was found following the CLR condition compared to the FWR control condition. However, no difference in peak and mean eccentric (8-10%; p>0.05) and concentric knee angular velocities (11-23%; p>0.05), or knee flexion angle (0.3%; p>0.05) occurred. No subjects increased 1-RM after the FWR condition, however 10 of 16 subjects (63%) increased 1-RM by ~10% after the CLR condition.
Discussion
Performing a CLR warm-up significantly enhanced subsequent free-weight 1-RM squat performance without changes in knee flexion angle. Thus, a real increase in 1-RM was achieved as the subjects clearly squatted to the same depth and did not compromise the mechanics of the lift. No change in concentric EMG activity occurred despite the increased load, which may indicate that the hip extensors were responsible for the greater muscle force production to be developed. Regardless, a greater 1-RM load was lifted following CLR as a warm up, which may enhance training stimuli.
Contact
m.mina@derby.ac.uk
... One distinct limitation in chain training is the lack of scientific research performed in this area; most claims are anecdotal and until conclusive evidence is presented, the proposed benefits remain hypothetical. Two studies, one by Coker et al. (12) and the other by Berning et al. (8), found that lifting with chains versus lifting without chains did not cause any changes in the kinematic and kinetic variables of the lifter during the snatch; which may have been due to the a low chain load (5% of the total load) used. In addition, only a limited number of kinematic and kinetic variables were measured in these studies, none of which truly reflected the technique of the lifters, giving sports scientists another reason to be skeptical of chain training. ...
RESISTANCE TRAINING METHODS HAVE BEEN BROADLY CLASSIFIED INTO 3 CATEGORIES: CONSTANT, ACCOMMODATING, AND VARIABLE RESISTANCE. VARIABLE RESISTANCE TRAINING METHODS, WHICH INCLUDES CAMS AND LEVERS, CHAINS, AND RUBBER-BASED RESISTANCE, WILL BE THE FOCUS OF THIS ARTICLE. THE KINEMATICS, KINETICS, AND HUMAN STRENGTH CURVE CHARACTERISTICS ASSOCIATED WITH THESE 3 TYPES OF VARIABLE RESISTANCE ARE DISCUSSED, GIVEN THAT EACH RESISTANCE TYPE MAY OFFER A UNIQUE SET OF MECHANICAL STIMULI AND, HENCE, MUSCULOSKELETAL ADAPTATIONS. THE PRACTICAL APPLICATIONS AND LIMITATIONS ASSOCIATED WITH EACH FORM OF VARIABLE RESISTANCE WILL ALSO BE CONSIDERED.
... Finally, driven by experience and fundamental understanding of training adaptation, exercise parameters need to be adjusted so as to address the identified limiting factors. The adjustment can come in different forms, such as a change in the repetition range, frequency, volume and intensity of training (Crewther et al. 2008), inclusion or exclusion of exercises, or the use of accommodating resistance (Swinton et al. 2009;Berning et al. 2008;Ebben and Jenson 2002;McCurdy et al. 2009;Arandjelović 2010). ...
The occurrence of so-called sticking points in a lift is pervasive in weight training practice. Biomechanically complex exercises often exhibit multi-modal variation of effective force exerted against the load as a function of the elevation and velocity of the load. This results in a variety of possible loci for the occurrence of sticking points and makes the problem of designing the optimal training strategy to overcome them challenging. In this article a case founded on theoretical grounds is made against a purely empirical method. It is argued that the nature of the problem considered and the wide range of variables involved limit the generality of conclusions which can be drawn from experimental studies alone. Instead an alternative is described, whereby a recently proposed mathematical model of neuromuscular adaptation is employed in a series of computer simulations. These are used to examine quantitatively the effects of differently targeted partial range of motion (ROM) training approaches. Counter-intuitively and in contrast to common training practices, the key novel insight inferred from the obtained results is that in some cases the most effective approach for improving performance in an exercise with a sticking point at a particular point in the ROM is to improve force production capability at a different and possibly remote position in the lift. In the context of the employed model, this result is explained by changes in the neuromuscular and biomechanical environment for force production.
... Accommodating resistance. In powerlifting training the term accommodating resistance refers to purposeful modifications of the effective load experienced in an exercise throughout a repetition (Swinton et al. 2009;Berning et al. 2008;Ebben and Jensen 2002;McCurdy et al. 2009). This can be achieved by fixing an elastic band between the load (such as a barbell) and the floor, as in Figure 1 (a). ...
A large corpus of data obtained by means of empirical study of neuromuscular adaptation is currently of limited use to athletes and their coaches. One of the reasons lies in the unclear direct practical utility of many individual trials. This paper introduces a mathematical model of adaptation to resistance training, which derives its elements from physiological fundamentals on the one side, and empirical findings on the other. The key element of the proposed model is what is here termed the athlete's capability profile. This is a generalization of length and velocity dependent force production characteristics of individual muscles, to an exercise with arbitrary biomechanics. The capability profile, a two-dimensional function over the capability plane, plays the central role in the proposed model of the training-adaptation feedback loop. Together with a dynamic model of resistance the capability profile is used in the model's predictive stage when exercise performance is simulated using a numerical approximation of differential equations of motion. Simulation results are used to infer the adaptational stimulus, which manifests itself through a fed back modification of the capability profile. It is shown how empirical evidence of exercise specificity can be formulated mathematically and integrated in this framework. A detailed description of the proposed model is followed by examples of its application-new insights into the effects of accommodating loading for powerlifting are demonstrated. This is followed by a discussion of the limitations of the proposed model and an overview of avenues for future work.
Heelas, T, Theis, N, and Hughes, JD. Muscle activation patterns during variable resistance deadlift training with and without elastic bands. J Strength Cond Res XX(X): 000-000, 2019-The purpose of this study was to determine the effects of band-assisted variable resistance training on muscular activity in the lower limbs and barbell kinematics during the concentric phase of the deadlift. Fifteen resistance trained men (mean ± SD: 28.7 ± 9.3 years; 1.80 ± 0.90 m; 92.5 ± 15.1 kg) performed 6 deadlift repetitions during 4 loading conditions: 100-kg bar (no band), 80-kg bar with 20-kg band tension (B20), 75-kg bar with 25-kg band tension (B25), and 70-kg bar with 30-kg band tension (B30). Muscle activity from the medial gastrocnemius (MG), semitendinosus (ST), vastus medialis (VMO), vastus lateralis (VL), and gluteus maximus (GM) were recorded using surface electromyography during the concentric phase of the lift and expressed as a percentage of each muscle's maximal activity, recorded during a maximal isometric contraction. Barbell power and velocity were recorded using a linear position transducer. Electromyography results showed that muscle activity significantly decreased as band resistance increased in the MG and ST (p < 0.05) and progressively decreased in the GM. No changes were observed for the VMO or VL. Peak and mean bar velocity and power significantly increased as band resistance increased. Performing the deadlift with band-assisted variable resistance increases bar power and velocity, while concurrently decreasing muscle activation of the posterior chain musculature. Practitioners prescribing this exercise may wish to include additional posterior chain exercises that have been shown to elicit high levels of muscle activation.
The use of a variable resistance (VR) combined with a traditional resistance exercise (TRE) has become increasingly popular amongst strength and conditioning practitioners as a method of training. Mostly anecdotal, the evidence has suggested that the addition of chains can improve strength and power, extend the duration of the acceleration phase and subsequently increase velocity during the concentric phase of a lift. Therefore, the purpose of this study was to investigate the combined acute effects of chain and TRE on force and power characteristics during the parallel back squat exercise. Following ethical approval and informed consent, six recreationally trained male sport and exercise science students (Mean age ± S.D. = 22.0 ± 1.9 years) performed single, maximal effort repetitions of the parallel back squat during 3 testing sessions using the following loading conditions: Session 1, baseline measures; Session 2, condition 1- 60% of 1-RM TRE; condition 2- 60% of 1-RM TRE as well as an additional 20% of chains (VR); condition 3- 60% of 1-RM TRE and an additional 35% of chains (VR); Session 3, condition 4- 85% of 1-RM TRE; condition 5- 85% of 1-RM TRE as well as an additional 20% of chains (VR); condition 6- 85% of 1-RM TRE and an additional 35% of chains (VR). All sessions were conducted 72 hours apart to account for fatigue effects. A ballistic measurement system (Fittech, Australia) calculated force and power characteristics. One-way repeated measures ANOVA revealed significant differences (p = 0.001) in peak force production between TRE and all VR conditions at 60% and 85% of 1-RM. Further analysis also revealed significant increases (p = 0.04) in the maximal rate of force development between TRE and 60% of 1-RM and an additional 20% of chains (condition 2). The acute effects of supplementing chains with TRE may enhance acceleration during the initial concentric phase of the squat, promote power output and elevate neural drive in recreationally trained athletes. However, coaches must acknowledge the limitations in chain training until conclusive evidence is presented.
RESUMO A Potencialização Pós-Ativação (PPA) é estratégia para melhora do desempenho com uso de carga fixa (RF), definida no ponto de falha mecânica (PFM). Por outro lado, o uso de correntes (CRT) é estímulo com resistência variável (RV). Assim, objetivou-se avaliar os efeitos do CRT na altura e tempo de voo do salto vertical com contramovimento (CMJ). A partir de estudo de intervenção, 15 sujeitos foram avaliados quanto à carga máxima no agachamento (1RM) e altura CMJ. Após isto, executaram três tipos de intervenções: i) RF com 85% de 1RM; ii) RV com 85% de 1RM posicionado no PFM (RV-TF) e, iii) RV com 85% de 1RM posicionado na maior extensão dos joelhos (RV-TV). Observou-se incremento do CMJ para RV-TF e RV-TV resistência. 1. In memorian.
Attaching chains to barbells to increase strength and power has become popular for athletes; however, little scientific evidence supports this practice. The present purpose was to compare chain training to traditional training for the bench press. Women collegiate athletes in volleyball and basketball (N = 19) participated in a 16-session bench press program. They were matched into either a Traditional or a Chain training group by 1-repetition maximum (1RM). The Traditional group performed the bench press with conventional equipment, while the Chain group trained with attached chains (5% of weight). Analysis showed a significant increase in 1RM for both groups over 16 sessions, Traditional +11.8% and Chain +17.4%. The difference between the groups was not statistically significant, but suggests the women who trained with attached chains improved their bench press more than the Traditional group.
In this work, we describe a simple coarse-grained model of a barbell that can be used to determine the qualitative role of bar bend during a jerk. In simulations of this model, we observed a narrow time window during which the lifter can leverage the elasticity of the bar in order to lift the weight to a maximal height. This time window shifted to later times as the weight was increased. In addition, we found that the optimal time to initiate the drive was strongly correlated with the time at which the bar had reached a maximum upward velocity after recoiling. By isolating the effect of the bar, we obtained a generalized strategy for lifting heavy weight in the jerk.
This study examined mean integrated electromyography (I-EMG) for the quadriceps and hamstring muscle groups, as well as mean and peak vertical ground reaction forces (GRFs), for 3 conditions of the back squat. Conditions included (a) squat with barbell and weight plates, (b) squat with barbell and weight plates plus chains hung on each end of the barbell to replace approximately 10% of the squat load, and (c) squat with barbell and weight plates plus elastic bands offering resistance equivalent to approximately 10% of the squat load. Weight plates equal to the load added by either the chains or elastic bands were removed for the latter 2 squat conditions. Vertical GRFs were obtained during a single testing session for all 3 squat conditions. The tests were performed on a 2-cm thick aluminum platform (0.76 x 1.0 m) bolted directly to a force plate (OR6-5-2000, AMTI, Watertown, MA). Surface electrode I-EMG data from the quadriceps and hamstrings were recorded at 500 Hz. The exercise order was randomly determined for 11 NCAA Division I athletes who had experience using these types of squats. A repeated measures analysis of covariance revealed no differences in I-EMG and GRF during the eccentric or concentric phase for any of the 3 squat conditions. Analyses showed that mean GRF and I-EMG was significantly different between eccentric and concentric phases for all groups. The results question the usefulness of performing squats combining barbell and weight plates with chain and elastic resistance.
For activities such as squash, badminton and fencing, the ability to quickly complete a lunge and return to the start or move off in another direction is critical for success. Determining which strength qualities are important predictors of lunge performance was the focus of this study. Thirty-one male athletes performed: (1) a unilateral maximal squat (one-repetition maximum, 1-RM) and unilateral jump squat (50% 1-RM) on an instrumented supine squat machine, and (2) a forward lunge while attached to a linear transducer. We performed stepwise multiple regression analysis with lunge performance as the dependent variable and various strength, flexibility and anthropometric measures as the independent variables. From the many strength and power measures calculated, time to peak force was the best single predictor of lunge performance, which accounted for 55% of the explained variance. The best three-variable model for predicting lunge performance accounted for 76-85% of the explained variance. The models differed, however, according to whether lunge performance was expressed relative to body mass (time to peak force, mean power and relative strength = 76%) or taken as an absolute value (time to peak force, leg length and flexibility = 85%). We conclude that one to two trials were reliable for strength diagnosis and that one strength measure cannot accurately explain functional performance because other factors, such as body mass, flexibility and leg length, have diverse effects on the statistical models.
Athletes commonly use elastic bands as a training method to increase strength and performance. The purpose of this study was to investigate the effect of elastic bands on peak force (PF), peak power (PP), and peak rate of force development (RFD) during the back-squat exercise (BSE). Ten recreationally resistance-trained subjects (4 women, 6 men, mean age 21.3 +/- 1.5 years) were tested for their 1 repetition maximum (1RM) in the BSE (mean 117.6 +/- 48.2 kg) on a Smith machine. Testing was performed on 2 separate days, with 2 sets of 3 repetitions being performed for each condition. Testing was conducted at 60% and 85% of 1RM with and without using elastic bands. In addition, 2 elastic band loading conditions were tested (B1 and B2) at each of the 2 resistances. No bands (NB) represents where all of the resistance was acquired from free-weights. B1 represents where approximately 80% of the resistance was provided by free-weights, and approximately 20% was provided by bands. B2 represents where approximately 65% of the resistance was provided by free-weights, and approximately 35% was provided from bands. The subjects completed the BSE under each condition, whereas PF, PP, and RFD was recorded using a force platform. There was a significant (p < 0.05) increase in PF between NB-85 and B2-85 of 16%. Between B1-85 and B2-85, PF was increased significantly by 5% (p < 0.05). There was a significant (p < 0.05) increase in PP between NB-85 and B2-85 of 24%. No significant differences were observed in RFD during the 85% conditions or for any of the measured variables during the 60% conditions (p < 0.05). The results suggest that the use of elastic bands in conjunction with free weights can significantly increase PF and PP during the BSE over free-weight resistance alone under certain loading conditions. The greatest differences are observed during the higher loading conditions, with the B1-85 condition appearing to be optimal for athletic performance of the ones we tested. The strength training professional could use variable resistance training (VRT) to increase PF and PP more than the traditional BSE can. VRT could also be used to train these 2 performance characteristics together, which might be especially useful in season, when weight-room training volume can sometimes be limited.
Designing Resistance Training Programs, Fourth Edition, is a guide to developing individualized training programs for both serious athletes and fitness enthusiasts. Two of the world’s leading experts on strength training explore how to design scientifically based resistance training programs, modify and adapt programs to meet the needs of special populations, and apply the elements of program design in the real world.
The fourth edition presents the most current information while retaining the studies that are the basis for concepts, guidelines, and applications in resistance training. Meticulously updated and heavily referenced, the fourth edition contains the following updates: A full-color interior provides stronger visual appeal.Sidebars focus on a specific practical question or an applied research concept, allowing readers to connect research to real-life situations.Multiple detailed tables summarize research from the text, offering an easy way to compare data and conclusions.A glossary makes it simple to find key terms in one convenient location.Newly added instructor ancillaries make the fourth edition a true learning resource for the classroom (available at www.HumanKinetics.com/DesigningResistanceTrainingPrograms).
Designing Resistance Training Programs, Fourth Edition, is an essential resource for understanding and applying the science behind resistance training for any population.
There are distinct differences between training for a strong man competition and training to improve athletic performance. However, there are facets of strong man training that are applicable to training many types of athletes. One example of this is integrating the use of water filled barrels as a form of resistance. Applying the concept of specificity, a fluid resistance provides a higher degree of sport specificity than a static resistance because for many athletes the type of resistance they encounter during competition is not static but moving. While a majority of our training is performed with a standard barbell or dumbbell, water filled barrels have become an important part of our training program.
Total energy expenditure and rate of energy expenditure (power output) are important considerations for exercise programs and training programs. Mechanical power output generated during competitive lifts in both weightlifting (WL) and powerlifting (PL) is large in magnitude and can be measured accurately using standard biomechanical analysis equipment. Power tests do not appear to have predictive value for performance capability in PL. However, athletes in WL produce power outputs in vertical jump tests that are similar to those they produce in selected phases of the competitive lifts. This fact and related data have led to research that may result in simple power test protocols useful for estimating the training and performance potential of weightlifters and other athletes in power oriented sports, as well as for measuring a power component in standard fitness testing packages. Thus the purposes of this paper are to (a) review what is known about power output during the competitive lifts of WL and PL and the methods used to evaluate it, (b) review what is known about power tests in relation to performance prediction in WL and PL, and (c) suggest applications of this knowledge to related fields of study.
(C) 1993 National Strength and Conditioning Association
summary: To maximize gains in size, speed, and strength, coaches may utilize alternative methods of training. Anecdotal evidence exists suggesting the effectiveness of chains as a resistance training modality. This article discusses that evidence as well as practical methods of incorporating chains in a resistance training program.
(C) 2004 National Strength and Conditioning Association
Testprotokolle, Testbeschreibungen unterschiedlichster Krafttests
Identifying and understanding the key biomechanical factors that exemplify the power clean can provide athletes the proper tools needed to prevail at a competitive event. Therefore, the purpose of this study was to characterize and describe ground reaction forces (Fz) during the power clean lift. Three 60-Hz motion-detecting cameras and an AMTI force plate were used to collect data from 10 collegiate weightlifting men who performed a power clean at 60 and 70% of their last competitive maximum clean. The results revealed that a greater peak force (Fz) was produced during the second pull compared with the first pull and unweighted phases in both percentage lifts. As the system weight increased from 60 to 70%, the peak force (Fz) increased for the first pull and unweighted phases and decreased during the second pull phase. Learning the proper technique of the power clean may provide athletes the basic understanding needed to be competitive in a weightlifting or sporting event.
Eccentric strength training is thought to be important for improving functional performance. A form of training that may enhance the eccentric training stimulus is the attachment of a rubber bungy to the strength-training apparatus in such a way that the return velocity and, therefore, the force required to decelerate the load at the end of the eccentric phase are increased. To determine the effects of elastic bungy training, we performed two studies. In the first, we examined the electromyographic (EMG) and kinematic characteristics of three different squat techniques: traditional squat, non-bungy jump squat and bungy jump squat. In the second study, we examined whether jump squat training with and without the attachment of a rubber bungy to an isoinertial supine squat machine affects muscle function, multidirectional agility, lunge ability and single leg jump performance. The EMG activity of the vastus lateralis and gastrocnemius muscles was recorded. An instrumented isoinertial supine squat machine was used to measure maximal strength and various force, velocity and power measures in both studies. Participants were randomly assigned to one of three groups: a control group and two weight-trained groups, one of which performed bungy squat jumps and one of which performed non-bungy squat jumps. The two experimental groups performed 10 weeks of ballistic weight training. The kinematic and EMG characteristics of the bungy and non-bungy squat techniques differed significantly from those of the traditional squat on all the variables measured. The only difference between the bungy squat and non-bungy squat training was greater EMG activity during the later stages (70-100%) of the eccentric phase of the bungy squat condition. The 10 weeks of bungy squat and non-bungy squat jump weight training were found to be equally effective in producing improvements in a variety of concentric strength and power measures (10.6-19.8%). These improvements did not transfer to improved performance for the single leg jump and multidirectional agility. However, bungy weight training did lead to a significant improvement in lunge performance (21.5%) compared with the other groups.
The purpose of this study was to determine whether the addition of chains to a barbell during the performance of the snatch would invoke differences in execution compared with lifting a conventional barbell without chains. Additionally, subjects were asked whether they perceived that the addition of chains had effects on their performance, and, if so, what those effects were. Four male and 3 female competitive weightlifters who regularly used chains as part of their training programs participated in the study. They were compared lifting 80% of 1 repetition maximum (1RM) using conventional barbells with 80% of 1RM, 5% of which was accounted for by chains. The same procedure was used with 85% of 1RM. Variables examined included maximum vertical displacement of the bar, maximum bar velocity, rate of force production of the bar, and vertical ground reaction forces for the first pull, unweighting, and second pull phases of the lift. Results indicated that there were no statistically significant differences between the chain vs. no-chain conditions at either 80% or 85% of 1RM. In contrast, 100% of the subjects stated that they perceived that the addition of chains made them work harder during the snatch. They suggested that the chains forced them to pull harder throughout the lift and that oscillation of the chains required their shoulders, abdominals, and back to work harder to stabilize the bar in the catch phase. Although statistical results indicate that chains have no influence on the snatch technique, chains may have a psychological impact and possibly invoke a physiological training response by increasing strength of muscles required to stabilize the bar during the catch phase if used over time.
Heavy elastic bands alter force, velocity and power output during back squat lift
- Ru Newton
- M Robertson
- E Dugan
- C Hasson
- J Cecil
- A Gerber
- J Hill
- L Schwier
Newton, RU, Robertson, M, Dugan, E, Hasson, C, Cecil, J, Gerber, A, Hill, J, and Schwier, L. Heavy elastic bands alter force, velocity and power output during back squat lift. J Strength Cond Res 16: 1–18, 2002
Chained down: a Pure power question and answer interview
- Jm Berning
Berning, JM. Chained down: a Pure power question and answer interview. Pure Power 5: 50–56, 2005.
Of stones, barbells and logs Eclectic strength training for rugby
- A Jones
Jones, A. Of stones, barbells and logs. Eclectic strength training for rugby. Milo 5: 109–112, 1998
Chain reactions: accommodating leverages
- Lp Simmons
Simmons, LP. Chain reactions: accommodating leverages. Powerlifting USA 19: 2–3, 1996.
A closer look at BFS chains. Bigger, Faster, Stronger Fall
- K Goss
Goss, K. A closer look at BFS chains. Bigger, Faster, Stronger Fall:
54–58, 2003.
The biomechanics of resistance exercise In: Essentials of Strength and Conditioning
- E Harman
Harman, E. The biomechanics of resistance exercise. In: Essentials of
Strength and Conditioning. Baechle, TR and Earle, RW, eds.
Champaign, IL: Human Kinetics Publishers, 2000. pp. 25–26.
Free weight variable resistance Available at: http://www.strengthcats.com/variableresistance.htm
- M Berry
- W Ebben
Berry, M and Ebben, W. Free weight variable resistance. Available at:
http://www.strengthcats.com/variableresistance.htm. Accessed
June 12, 2006.
The science behind bands and chains Available at: http:// www.elitefts.com/documents/sciencebehindbandsandchains.htm
- R Haan
Haan R. The science behind bands and chains. Available at: http://
www.elitefts.com/documents/sciencebehindbandsandchains.htm.
Accessed June 12, 2006.