Article

Improvement in Running Economy After 6 Weeks of Plyometric Training

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Abstract

This study determined whether a 6-week regimen of plyometric training would improve running economy (i.e., the oxygen cost of submaximal running). Eighteen regular but not highly trained distance runners (age = 29 +/- 7 [mean +/- SD] years) were randomly assigned to experimental and control groups. All subjects continued regular running training for 6 weeks; experimental subjects also did plyometric training. Dependent variables measured before and after the 6-week period were economy of running on a level treadmill at 3 velocities (women: 2.23, 2.68, and 3.13 m.s(-1); men: 2.68, 3.13, and 3.58 m.s(-1)),VO(2)max, and indirect indicators of ability of muscles of lower limbs to store and return elastic energy. The last were measurements during jumping tests on an inclined (20 degrees ) sled: maximal jump height with and without countermovement and efficiencies of series of 40 submaximal countermovement and static jumps. The plyometric training improved economy (p < 0.05). Averaged values (m.ml(-1).kg(-1)) for the 3 running speeds were: (a). experimental subjects-5.14 +/- 0.39 pretraining, 5.26 +/- 0.39 posttraining; and (b). control subjects-5.10 +/- 0.36 pretraining, 5.06 +/- 0.36 posttraining. The VO(2)max did not change with training. Plyometric training did not result in changes in jump height or efficiency variables that would have indicated improved ability to store and return elastic energy. We conclude that 6 weeks of plyometric training improves running economy in regular but not highly trained distance runners; the mechanism must still be determined.

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... Despite long periods (14-20 weeks) necessary to improve aerobic parameters with submaximal endurance training , runners typically employ a training intensity distribution that involves ⁓70-90% of training volume in the moderateintensity domain (Casado et al., 2022). However, some studies suggest that RT added to submaximal aerobic training improve physiological and neuromuscular parameters after few weeks (Guglielmo et al., 2009;Turner et al., 2003). ...
... However, despite the RT result in specific adaptations according the load and the number of repetitions performed (Burd et al., 2012), any responses are attenuated when RT and endurance training are performed concurrently (Balsalobre-Fernández et al., 2016;Blagrove et al., 2018). In this sense, although RT protocols as heavy resistance training (HRT) and explosive resistance training (ERT) show significant improvements in physiological parameters (Denadai et al., 2006;Millet et al., 2002;Paavolainen et al., 1999;Spurrs et al., 2003;Turner et al., 2003) and performance (Denadai et al., 2006;Paavolainen et al., 1999;Spurrs et al., 2003), inconsistencies exist within the literature, which can be related to differences in methodologies and characteristics of athletes. Thus, the influence of two different based-RT protocols performed with standard submaximal endurance training in well-trained runners is still uncertain. ...
... The CMJ was higher in HRT and ERT than 6 weeks of plyometric training (Turner et al., 2003), which may be associated with the reduced experience with resistance training of the present athletes. Furthermore, despite increased in all groups, was verified higher differences in EST than HRT and HIIT groups, which may be explained by the dependence between the RT applied and the following adaptation (Guglielmo et al., 2009). ...
Article
This study aimed to verify the effects of 4 weeks of high-intensity interval training (HIIT), heavy (HRT) and explosive (ERT) resistance training on aerobic, anaerobic and neuromuscular parameters and performance of well-trained runners. Twenty-six male athletes were divided into HIIT (n = 10), HRT (n = 7) and ERT (n = 9) groups. Maximal oxygen uptake (VO2max) and the corresponding velocity (vVO2max), anaerobic threshold (AT), running economy (RE), oxygen uptake kinetics, lower-body strength (1RM) and power (CMJ), and the 1500 m and 5000 m time-trial (TT) were determined. Improvements were observed in vVO2max (mean difference (Δ): 2.6%; effect size (ES): 0.63) with HIIT, while AT was incresead in ERT (Δ: 4.3%; ES: 0.73) and HRT (Δ: 6.9%; ES: 0.72) groups. The CMJ performance was increased in ERT (Δ: 13.8%; ES: 1.03), HRT (Δ: 6.9%; ES: 0.55) and HIIT (Δ: 5.4%; ES: 0.34), whereas 1RM increase in HRT (Δ: 38.1%; ES: 1.21) and ERT (Δ: 49.2%; ES: 0.96) groups. HIIT improved the 1500 m (Δ: −2.3%; ES: −0.62) and both HRT (Δ: −1.6%; ES: −0.32) and ERT (Δ: −1.7%; ES: −0.31) the 5000 m TT. Despite performance adaptations were dependent on the training characteristics, both RT and HIIT model constitute an alternative for training periodization.
... Secondly, maximal aerobic capacity remains unaltered by hopping if regular running and exercise habits are maintained. Our findings are in line with earlier studies examining plyometric interventions in amateur athletes 22 and highly trained runners 18 . They also corroborate the observation of Saunders et al. 18 that the effects of plyometrics on running economy are more pronounced at higher running speeds. ...
... They also corroborate the observation of Saunders et al. 18 that the effects of plyometrics on running economy are more pronounced at higher running speeds. However, in contrast to the previous trials which used three weekly sessions with durations of up to 30 min as well as multiple jump exercises 18,22 , this study applied short daily bouts (net duration 5 min) consisting of one simple and easy-to-learn hopping exercise only. Our results suggest that regular endurance and concurrent plyometric training can be performed jointly by amateur runners, without complex programs and at a high frequency without leading to adverse events such as overuse injuries or pain. ...
... This study provides first evidence that 5 min of daily hopping improve RE at moderate and high running speed without compromising maximal aerobic capacity in amateur runners. This is in line with previous studies using less frequent jump exercises with higher duration 18,22 . The more frequent units nevertheless appear to be feasible and safe. ...
Article
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This study investigated the effects of a daily plyometric hopping intervention on running economy (RE) in amateur runners. In a randomized, controlled trial, thirty-four amateur runners (29 ± 7 years, 27 males) were allocated to a control or a hopping exercise group. During the six-week study, the exercise group performed 5 min of double-legged hopping exercise daily. To progressively increase loading, the number of hopping bouts (10 s each) was steadily increased while break duration between sets was decreased. Pre- and post-intervention, RE, peak oxygen uptake (VO2peak), and respiratory exchange ratio (RER) were measured during 4-min stages at three running speeds (10, 12, and 14 km/h). ANCOVAs with baseline values and potential cofounders as cofactors were performed to identify differences between groups. ANCOVA revealed an effect of hopping on RE at 12 km/h (df = 1; F = 4.35; p < 0.05; η² = 0.072) and 14 km/h (df = 1; F = 6.72; p < 0.05; η² = 0.098), but not at 10 km/h (p > 0.05). Exercise did not affect VO2peak (p > 0.05), but increased RER at 12 km/h (df = 1; F = 4.26; p < 0.05; η² = 0.059) and 14 km/h (df = 1; F = 36.73; p < 0.001; η² = 0.520). No difference in RER was observed at 10 km/h (p > 0.05). Daily hopping exercise is effective in improving RE at high running speeds in amateurs and thus can be considered a feasible complementary training program. Clinical trial registration German Register of Clinical Trials (DRKS00017373).
... Consistently, there was a significant improvement of RE ranging from 2 -4.1% for at least one of the tested submaximal running speeds while V Ȯ_2max did not change. Generally, subjects improved their strength or jump performance while this did not apply for the study by Turner et al. (2003) (Turner et al., 2003). However, in their study RE was improved for all three submaximal running speeds. ...
... Consistently, there was a significant improvement of RE ranging from 2 -4.1% for at least one of the tested submaximal running speeds while V Ȯ_2max did not change. Generally, subjects improved their strength or jump performance while this did not apply for the study by Turner et al. (2003) (Turner et al., 2003). However, in their study RE was improved for all three submaximal running speeds. ...
... The fact that explosive strength training, in this case concentric training (Guglielmo et al., 2009), appears less effective may indicate the recruitment being of minor importance. I may therefore be argued that the high eccentric forces generated during plyometric training (Saunders et al., 2004;Spurrs et al., 2003;Turner et al., 2003) or submaximal and maximal strength training (Albracht & Arampatzis, 2013;Guglielmo et al., 2009) are providing the most effective stimulus. This interpretation is well documented in the study by Albracht and Arampatzis (2013) which identifies the stiffness, in this case the thickness, of the tendon in combination with greater muscular strength as a prerequisite for improving energy storage and release. ...
Article
Context: This article systematically reviews the available literature on biomechanically motivated interventions to improve running economy aside from conventional endurance training. It was aimed to identify the possible mechanisms behind the potential improvements and to extract principles to guide researchers and coaches in how to make use of this potential. Evidence acquisition: The search strategy yielded 26 intervention papers and four reviews which were suitable for inclusion. Results: It was concluded that plyometric and strength training protocols were consistently beneficial to reduce the oxygen consumption per distance traveled in steady state running showing an average effect size of 3.8%. Footwear interventions showed smaller effects of 1.9% on average but still may offer considerable improvements which can potentially be applied immediately. Conclusions: It was suggested that the energy consumption savings achieved by footwear interventions are not realizable by energy return mechanisms of the footwear alone. It is most likely that footwear assists to improve RE by optimizing energy storage and return mechanisms within the biological system. Future research should aim at verifying this interplay to provide more efficient training programs as well as footwear which ameliorates the utilization of the mechanisms embedded within the human locomotor system.
... Consistently, there was a significant improvement of RE ranging from 2 -4.1% for at least one of the tested submaximal running speeds while V Ȯ_2max did not change. Generally, subjects improved their strength or jump performance while this did not apply for the study by Turner et al. (2003) (Turner et al., 2003). However, in their study RE was improved for all three submaximal running speeds. ...
... Consistently, there was a significant improvement of RE ranging from 2 -4.1% for at least one of the tested submaximal running speeds while V Ȯ_2max did not change. Generally, subjects improved their strength or jump performance while this did not apply for the study by Turner et al. (2003) (Turner et al., 2003). However, in their study RE was improved for all three submaximal running speeds. ...
... The fact that explosive strength training, in this case concentric training (Guglielmo et al., 2009), appears less effective may indicate the recruitment being of minor importance. I may therefore be argued that the high eccentric forces generated during plyometric training (Saunders et al., 2004;Spurrs et al., 2003;Turner et al., 2003) or submaximal and maximal strength training (Albracht & Arampatzis, 2013;Guglielmo et al., 2009) are providing the most effective stimulus. This interpretation is well documented in the study by Albracht and Arampatzis (2013) which identifies the stiffness, in this case the thickness, of the tendon in combination with greater muscular strength as a prerequisite for improving energy storage and release. ...
Article
Full-text available
Background: This article systematically reviews the available literature on biomechanically motivated interventions to improve running economy aside from conventional endurance training. It was aimed to identify the possible mechanisms behind the potential improvements and to extract principles to guide researchers and coaches in how to make use of this potential. Evidence acquisition: The search strategy yielded 26 intervention papers and four reviews which were suitable for inclusion. Results: It was concluded that plyometric and strength training protocols were consistently beneficial to reduce the oxygen consumption per distance traveled in steady state running showing an average effect size of 3.8%. Footwear interventions showed smaller effects of 1.9% on average but still may offer considerable improvements which can potentially be applied immediately. Conclusions: It was suggested that the energy consumption savings achieved by footwear interventions are not realizable by energy return mechanisms of the footwear alone. It is most likely that footwear assists to improve RE by optimizing energy storage and return mechanisms within the biological system. Future research should aim at verifying this interplay to provide more efficient training programs as well as footwear which ameliorates the utilization of the mechanisms embedded within the human locomotor system.
... However, strength-training interventions seem to improve RE more robustly. Plyometric jump training (PJT) is one such strength training method shown to improve RE, with small increases in economy observed in a variety of sports (Balsalobre-Fernandez et al., 2016;Paavolainen et al., 1999;Turner et al., 2003). ...
... This improvement of the SSC is probably derived from increased stiffness in tendons resulting in a more efficient storage and subsequent release of elastic energy (Saunders et al., 2004). However, research is inconclusive regarding the mechanism as PJT can improve RE without any significant differences in counter movement jump (CMJ) height (Turner et al., 2003), a test that normally indicates an improvement in the SSC. Most PJT interventions have tested RE on a treadmill before and after the intervention and usually at moderate speeds. ...
... Interestingly, we did not find any substantial changes in force plate drop-jump variables ( Figure 2) indicating a lack of biomechanical adaptations throughout the intervention. An absence of change in jumping performance has previously been reported after short term PJT (Turner et al., 2003). We can therefore only speculate on the physiological changes that were responsible for the improvement in RE. ...
Article
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The present study investigated the effects of plyometric jump training on hard and soft surfaces on running economy (RE), maximal oxygen uptake (VO2max), running performance and the rate of force development in orienteers. Nineteen orienteers (11 women and 8 men, body mass 61.1 ± 7.3 kg, age 21 ± 5.8 yrs) were randomly stratified based on sex, age, VO2max and RE to plyometric jumping training (8 sessions over 4 weeks) on either a hard or a soft surface. RE, VO2max and running performance were assessed on a treadmill and outdoor on- and off-trail loops. Moreover, ground reaction forces and force development were assessed during a one leg drop-jump test. The training intervention led to an overall 2-7% improvement in treadmill and off-trail RE, independent of the jumping surface and running velocity assessed. These improvements were not explained by force development during drop jump tests, which remained unchanged following the intervention. The changes in time-trial performance were associated with changes in RE. Plyometric training improved RE with no difference between the hard or the soft training surface and improved RE was also independent of the running speed assessed. Furthermore, improved running performance was associated with changes in RE after the intervention.
... Improvements in the latter have been associated with plyometric training (27). Plyometric training involves an eccentric muscle contraction followed immediately by a concentric contraction to allow the muscle to store and return elastic energy (5,31). Studies have demonstrated a 4-8% enhanced RE following a structured plyometric training program (5,22,27,28) in addition to concomitant improvements of 2.6-5% in 3-km and 5-km time trial (TT) runs (5,22,23,28). ...
... Bilateral drop jumps have reportedly had a positive effect on RE and time trial performance (5,25). In addition, combined unilateral and bilateral jumps, hops and bounds have demonstrated significant improvements in RE (22,23,27,28,31). However, it is not clear from the available literature whether each plyometric training method individually may offer superior benefits in optimizing muscle tendon unit stiffness in distance runners. ...
... They reported a large improvement in RE (7%, ES = 1.01) whereas peak VO2 remained unchanged. Previous plyometric training programs used to enhance RE have demonstrated lower magnitudes of improvement (3.0-6.0%) after 6-9 weeks of 2-3 moderate to high-volume, low to moderate intensity combine unilateral and bilateral plyometric training sessions per week in moderately to well-trained distance runners (27,28,31) with no change in VO2max. Various factors may have contributed to the magnitudes of change differences in RE between low-volume, high intensity versus high volume, low intensity based plyometric training programs. ...
Article
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The purpose of the study was to investigate the effects of an 11-week unilateral versus bilateral plyometric training intervention on maximal isometric voluntary (MVC) knee extensor torque, countermovement jump height (CMJ), running economy (RE) and 3-km time trial (TT) performance. Twenty-seven recreationally trained endurance runners (12 females and 15 males) were randomly assigned to one of three groups: unilateral plyometric training (UPT; n = 9), bilateral plyometric training (BPT; n = 9) and control (CON; n = 9). RE, VO2max, 3-km treadmill TT, isometric MVC (bilateral and unilateral) and CMJ (bilateral and unilateral) were measured prior to and after 11 weeks of training (UPT and BPT; volume equated, 20-40 minutes, 2-3 days/week). Separate two-way repeated measures ANOVAs were used to assess within and between group differences in RE, VO2max, 3-km TT, maximal isometric knee extensor torque and CMJ. Following 11 weeks of plyometric training there were significant improvements in RE (UPT 5.6%; BPT 4.9%, p < 0.01) and 3-km TT performance (UPT 2.4%; BPT 2.5%, p < 0.01) in addition to CMJ (UPT 12.5%; BPT 14.5%, p < 0.01) and maximal isometric knee extensor torque in the unilateral group (14.0%, p < 0.01). No significant differences in VO2max or anthropometric measures were detected (p > 0.05). No statistically significant differences between training interventions (p > 0.05) were detected in any measure. These data demonstrate that UPT and BPT result in similar improvements in RE and 3-km TT run performance in recreational distance runners.
... Improvements in the latter have been associated with plyometric training (27). Plyometric training involves an eccentric muscle contraction followed immediately by a concentric contraction to allow the muscle to store and return elastic energy (5,31). Studies have demonstrated a 4-8% enhanced RE following 6-9 weeks of structured plyometric training ranging widely in volumes and intensities (5,22,27,28) in addition to concomitant improvements of 2.6-5% in 3-km and 5-km time trial (TT) runs (5,22,23,28) in trained endurance runners. ...
... Bilateral drop jumps have reportedly had a positive effect on RE and time trial performance (5,25). In addition, combined unilateral and bilateral jumps, hops and bounds have demonstrated significant improvements in RE (22,23,27,28,31). However, it is not clear from the available literature whether each plyometric training method individually may offer superior benefits in optimizing muscle tendon unit stiffness in distance runners. ...
... Weekly running volume (km) Previous plyometric training programs used to enhance RE have demonstrated lower magnitudes of improvement (3.0-6.0%) after 6-9 weeks of 2-3 moderate to high-volume, low to moderate intensity combine unilateral and bilateral plyometric training sessions per week in moderately to well-trained distance runners (27,28,31) with no change in VO2max. Various factors may have contributed to the magnitudes of change differences in RE between low-volume, high intensity versus high volume, low intensity based plyometric training programs. ...
Article
Full-text available
The purpose of the study was to investigate the effects of an 11-week unilateral versus bilateral plyometric training intervention on maximal isometric voluntary (MVC) knee extensor torque, countermovement jump height (CMJ), running economy (RE) and 3-km time trial (TT) performance. Twenty-seven recreationally trained endurance runners (12 females and 15 males) were randomly assigned to one of three groups: unilateral plyometric training (UPT; n = 9), bilateral plyometric training (BPT; n = 9) and control (CON; n = 9). RE, VO2max, 3-km treadmill TT, isometric MVC (bilateral and unilateral) and CMJ (bilateral and unilateral) were measured prior to and after 11 weeks of training (UPT and BPT; volume equated, 20-40 minutes, 2-3 days/week). Separate two-way repeated measures ANOVAs were used to assess within and between group differences in RE, VO2max, 3-km TT, maximal isometric knee extensor torque and CMJ. Following 11 weeks of plyometric training there were significant improvements in RE (UPT 5.6%; BPT 4.9%, p < 0.01) and 3-km TT performance (UPT 2.4%; BPT 2.5%, p < 0.01) in addition to CMJ (UPT 12.5%; BPT 14.5%, p < 0.01) and maximal isometric knee extensor torque in the unilateral group (14.0%, p < 0.01). No significant differences in VO2max or anthropometric measures were detected (p > 0.05). No statistically significant differences between training interventions (p > 0.05) were detected in any measure. These data demonstrate that UPT and BPT result in similar improvements in RE and 3-km TT run performance in recreational distance runners.
... Plyometric training-which entails movements requiring rapid eccentric contraction followed by a concentric contraction such that the stretch-shortening mechanism of the muscle-tendon unit is engaged-is consistently reported to decrease knee abduction during landing (4,26) and risk of knee injury (20,31) in female court-sport and field-sport athletes. Furthermore, plyometrics can improve running economy and performance (14,40). In light of those findings, investigation of strength and plyometric training as a method to alter kinematics related to risk of knee injury and performance among runners was warranted. ...
... The next 2 weeks progressed to multijoint lower extremity exercises including squats and lunges. The last 4 weeks involved plyometric exercises, such as hops and jumps, which have been reported to improve performance and/or alter spatiotemporal variables during running, suggesting their potential to alter joint kinematics (14,35,40). Plyometric exercises were instructed to be performed at maximal effort, as quickly as possible (i.e., minimizing ground contact time) (14). ...
Article
Harrison, K, Williams, DSB III, Darter, BJ, Zernicke, RF, Shall, M, and Finucane, S. Effect of strength and plyometric training on kinematics in female novice runners. J Strength Cond Res XX(X): 000–000, 2024—Both running performance and injury have been associated with running kinematics. Plyometric training improves run performance and reduces injury risk in court-sport and field-sport athletes. The aim of this study was to assess longitudinal changes in kinematics in novice runners before and after a typical beginners' running program, compared with those who perform a plyometric intervention before running. Fifty-seven novice female runners were assigned to the control group (8 weeks walking +8 weeks running) or the intervention group (8 weeks strength or plyometric training +8 weeks running). Kinematics were assessed at baseline, 8 weeks, and 16 weeks. Joint angles throughout the stride of those who completed the training ( n = 21) were compared between groups and assessment time points using a statistical parametric mapping 2-way analysis of variance, with group and study time point as independent variables. There was no interaction effect of group and study time point ( p > 0.05), indicating that both training programs had similar effects on running kinematics. There was a main effect of time for sagittal plane knee and hip kinematics ( p < 0.001); after training, subjects ran with a more extended leg, particularly during swing. Programs of 8 weeks of preparatory training, followed by 8 weeks of running, resulted in altered sagittal plane biomechanics, which have previously been related to improved running economy. A greater volume of plyometric, run training or concurrent plyometric and run training may be required to elicit changes in running form associated with lower injury risk.
... It is important to note that four out of the six articles implemented PT together with other training methods such as HIIT, sprint or COD training, so that must always be considered when interpreting the results. We could speculate that the positive results might be attributed to improvements in running economy that are common with PT, but improvements in running economy may occur independent of changes in VO2max (Barnes & Kilding, 2015;Saunders et al., 2006;Turner, Owings, & Schwane, 2003). In their study with low-level runners, Turner et al. (2003) emphasized that PT improved running economy without altering the indicators of the ability of muscles to return strain energy, explaining that the improvement might have occurred by way of a mechanism not involving storage and return of elastic energy, or it involved enhanced storage and return of elastic energy but in a way that could not be detected with the indirect measurements used. ...
... We could speculate that the positive results might be attributed to improvements in running economy that are common with PT, but improvements in running economy may occur independent of changes in VO2max (Barnes & Kilding, 2015;Saunders et al., 2006;Turner, Owings, & Schwane, 2003). In their study with low-level runners, Turner et al. (2003) emphasized that PT improved running economy without altering the indicators of the ability of muscles to return strain energy, explaining that the improvement might have occurred by way of a mechanism not involving storage and return of elastic energy, or it involved enhanced storage and return of elastic energy but in a way that could not be detected with the indirect measurements used. Alterations in running mechanics that allow for better coordination and timing of ground force application would offer a mechanism to improve running economy (Saunders, et al., 2006), so that might be another explanation for the benefits of PT. ...
Article
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This systematic scoping review aimed to comprehensively identify and analyze the available evidence pertaining to the effects of plyometric training interventions on handball players. The search for relevant literature was conducted across prominent databases, including PubMed, Scopus, SPORTDiscus, and Web of Science Core Collection. The eligibility criteria focused on healthy handball players, without restrictions on age, sex, or competitive level, who were exposed to plyometric training interventions, either alone or in combination with other training methods. A meticulous screening process was conducted, whereby 3,195 titles were carefully evaluated, resulting in the inclusion of 35 eligible studies in this systematic scoping review, involving a total of 891 participants. Most studies on plyometric training in handball focused on indoor settings, conducted during the in-season period, and involved tier two athletes. The training frequency typically ranged from twice per week, with a duration of between 5 and 12 weeks, and incorporated some form of progressive overload. The number of total floor contacts varied between 20 and 600. There was a considerable variation in outcomes across the included studies, but most of them demonstrated a positive impact of plyometric training on improving jumping ability, sprinting speed, change of direction, strength, and balance. In conclusion, the predominant focus of the studies was on the lower limb, specifically aiming to assess the intervention influence on variables associated with strength and power. Notably, these investigations consistently highlighted favorable effects on enhancing these parameters among handball players. However, further research is needed to explore the effects of plyometric training in handball, particularly regarding exercise selection, optimal volume and intensity, rest intervals, and tapering protocols.
... We considered them as a single study per one research group, and consequently, a total of 21 studies were finally adopted, in which running economy [63-68, 70-75, 78-83] and running time trial performance [65, 67, 69, 76-78, 80-82, 84] were assessed in 18 and 10 studies, respectively. The selected 22 articles were divided into the following training categories: 13 included heavy resistance training [63][64][65][66][67][68][69][70][71][72][73][74][75] and 9 included plyometric training [76][77][78][79][80][81][82][83][84]. ...
... The training period was found to influence the effect on running economy as discussed later, and it has been suggested that plyometric training over ≥ 10 weeks would maximize one's probability of obtaining significant improvements in jumping performance [86], which could consequently enhance running performance [87,88]. Despite these previous findings, six of eight studies have conducted plyometric training for 6 weeks or shorter [78,79,[82][83][84], which may not have been sufficient to substantially improve running economy. While there is room for future consideration [89], we may say that plyometric training over ≥ 10 weeks period would be needed to improve running economy. ...
Article
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Background As an adjunct to running training, heavy resistance and plyometric training have recently drawn attention as potential training modalities that improve running economy and running time trial performance. However, the comparative effectiveness is unknown. The present systematic review and meta-analysis aimed to determine if there are different effects of heavy resistance training versus plyometric training as an adjunct to running training on running economy and running time trial performance in long-distance runners. Methods Electronic databases of PubMed, Web of Science, and SPORTDiscus were searched. Twenty-two studies completely satisfied the selection criteria. Data on running economy and running time trial performance were extracted for the meta-analysis. Subgroup analyses were performed with selected potential moderators. Results The pooled effect size for running economy in heavy resistance training was greater ( g = − 0.32 [95% confidence intervals [CIs] − 0.55 to − 0.10]: effect size = small) than that in plyometric training ( g = -0.13 [95% CIs − 0.47 to 0.21]: trivial). The effect on running time trial performance was also larger in heavy resistance training ( g = − 0.24 [95% CIs − 1.04 to − 0.55]: small) than that in plyometric training ( g = − 0.17 [95% CIs − 0.27 to − 0.06]: trivial). Heavy resistance training with nearly maximal loads (≥ 90% of 1 repetition maximum [1RM], g = − 0.31 [95% CIs − 0.61 to − 0.02]: small) provided greater effects than those with lower loads (< 90% 1RM, g = − 0.17 [95% CIs − 1.05 to 0.70]: trivial). Greater effects were evident when training was performed for a longer period in both heavy resistance (10–14 weeks, g = − 0.45 [95% CIs − 0.83 to − 0.08]: small vs. 6–8 weeks, g = − 0.21 [95% CIs − 0.56 to 0.15]: small) and plyometric training (8–10 weeks, g = 0.26 [95% CIs − 0.67 to 0.15]: small vs. 4–6 weeks, g = − 0.06 [95% CIs 0.67 to 0.55]: trivial). Conclusions Heavy resistance training, especially with nearly maximal loads, may be superior to plyometric training in improving running economy and running time trial performance. In addition, running economy appears to be improved better when training is performed for a longer period in both heavy resistance and plyometric training.
... 11 Moreover, several experimental studies have reported the effectiveness of plyometric training in improving RE, supported by the strong relationship between leg tendon stiffness and performance in continuous running. 5,12,13 In addition, even a short-term plyometric intervention has shown beneficial effects on RE 14 and running performance. 15 Recently, Balsalobre-Fernández and colleagues 2 attributed the improvement in RE to strength training. ...
... The plyometric training intervention lasted for 7 weeks, as this time frame had shown to be adequate for significant endurance-related adaptations. 13 Before the initiation of the plyometric training period, the athletes were instructed as to the proper execution of all the exercises to be done during this period. The plyometric training took place 1 day per week, in this study specifically on Saturday for a matter of standardization and logistics. ...
Article
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The aim of this 4‐armed parallel group randomized‐controlled trial was to evaluate if plyometric training could have different effects on running performance and physiological adaptations depending on the training intensity distribution (TID) in an 8‐week intervention in endurance athletes. Sixty well‐trained male runners (age: 34 ± 6 years, relative ⩒O2peak: 69 ± 3 mL·kg‐1·min‐1) were recruited and allocated to a pyramidal (PYR), pyramidal + plyometric training (PYR+PLY), polarized (POL), and polarized + plyometric training (POL+PLY) periodization. The periodization patterns were isolated manipulations of TID, while training load was kept constant. Participants were tested pre‐ and post‐intervention for body mass, velocity at 2 and 4 mmol·L‐1 of blood lactate concentration (vBLa2, vBLa4), absolute and relative ⩒O2peak and 5‐km running time trial performance, counter movement jump and squat jump. There were significant group x time interactions for vBla4 (P = 0.0235), CMJ (P = 0.0234), SJ (P = 0.0168), and 5‐km running time trial performance (P = 0.0035). Specifically, vBla4 and 5‐km running time trial performance showed the largest post‐intervention improvements in PYR+PLY (2.4% and 1.6%) and POL+PLY (2.1% and 1.8%), respectively. No significant interactions were observed for body mass, absolute and relative ⩒O2peak, peak heart rate, lactate peak and rating of perceived exertion. In conclusion, an 8‐week training periodization seems to be effective in improving performance of well‐trained endurance runners. Including plyometric training once a week appeared to be more efficacious in maximizing running performance improvements, independently from the TID adopted.
... Plyometric training involves an immediate shortening (concentric contraction) after pre-stretching (eccentric contraction) the active muscle and has traditionally been used for various sports which are dependent on speed and power. Plyometric training can show improvements in leg strength and muscle power [6], acceleration (sprint) [7], running performance [7,8] and can lead to an increase in agility [8]. According to Oxfeldt, training regimes can improve jumping and sprint performance, and can reduce the likelihood of injuries occurring [9]. ...
... Plyometric training involves an immediate shortening (concentric contraction) after pre-stretching (eccentric contraction) the active muscle and has traditionally been used for various sports which are dependent on speed and power. Plyometric training can show improvements in leg strength and muscle power [6], acceleration (sprint) [7], running performance [7,8] and can lead to an increase in agility [8]. According to Oxfeldt, training regimes can improve jumping and sprint performance, and can reduce the likelihood of injuries occurring [9]. ...
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The main objectives of this study were to evaluate the short-term effects of resisted sprint and plyometric training on sprint performance together with lower limb physiological and functional performance in collegiate football players. Ninety collegiate football players participated in this three-arm, parallel group randomized controlled trial study. Participants were randomly divided into a control group and two experimental groups: resisted sprint training (RST) (n = 30), plyometric training (PT) (n = 30), and a control group (n = 30). Participants received their respective training program for six weeks on alternate days. The primary outcome measures were a knee extensor strength test (measured by an ISOMOVE dynamometer), a sprint test and a single leg triple hop test. Measurements were taken at baseline and after 6 weeks post-training. Participants, caregivers, and those assigning the outcomes were blinded to the group assignment. A mixed design analysis of variance was used to compare between groups, within-group and the interaction between time and group. A within-group analysis revealed a significant difference (p < 0.05) when compared to the baseline with the 6 weeks post-intervention scores for all the outcomes including STN (RST: d = 1.63; PT: d = 2.38; Control: d = 2.26), ST (RST: d = 1.21; PT: d = 1.36; Control: d = 0.38), and SLTHT (RST: d = 0.76; PT: d = 0.61; Control: d = 0.18). A sub-group analysis demonstrated an increase in strength in the plyometric training group (95% CI 14.73 to 15.09, p = 0.00), an increase in the single leg triple hop test in the resisted sprint training group (95% CI 516.41 to 538.4, p = 0.05), and the sprint test was also improved in both experimental groups (95% CI 8.54 to 8.82, p = 0.00). Our findings suggest that, during a short-term training period, RST or PT training are equally capable of enhancing the neuromechanical capacities of collegiate football players. No adverse events were reported by the participants.
... free-weights) as compared with normal resistance training or explosive-strength training. The basis of Plyometrics revolves around the Stretch Shortening Cycle (SSC), which involves the storage and expression of rapid force from a preceding eccentric contraction into a concentric contraction, therefore causing propulsive movement (17,22,26,29). Likewise, stiffness within the muscle-tendon junction has been shown to increase after engaging in plyometric training, leading to the belief that a more compliant MTU may not elicit the desired energy storage and utilisation capacity as would a stiffer structure (1,2,7,11,12). ...
... Despite falling short, this posed the question; 'What can be done to further increase performance?'. Minor improvements in RE (2-3%) may seem marginal on paper, but practically speaking, this may dictate an athlete's ability to beat a personal time, or even run a sub-two-hour marathon (29). However, velocities during testing procedures between interventions were maximised at 18km/h, which proves to be slightly slower than marathon pace (~20-22km/h), raising the questions, 1) will sub-race pace testing be appropriate for elite marathoners, and 2) how do such performance qualities transfer into running performance such as time trials? ...
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BLUF Appropriate periodisation of explosive-based resistance training methods such as Plyometrics has the ability to improve both physiological and neurological adaptations of musculotendinous units within the major joints of the lower body in endurance runners. ABSTRACT Strength and Power training modalities continue to emerge amongst elite-level endurance athletes. Despite common misconceptions surrounding such training, enhancements in overall running performance, most notably Running Economy, has the ability for individuals to overcome their competitors. A total of seven original experimental articles were used for this review. The primary finding from this review was that endurance performance characteristics, specifically Running Economy, were enhanced after participating in strength and power-based training (2-8%). Improvements in Rate of Force Development with a concomitant decreased demand for oxygen at a given speed showed improvements in time trials and time to exhaustion. Differing magnitudes of results may be due to subjects previous history, exercise selection, volume load and testing protocols. There was shown to be a lack of direct measurement for the stiffness and/or compliance qualities of the Musculotendinous Unit from the studies chosen. Strength and Power based training has the potential to elicit positive enhancements in performance characteristics amongst elite-level endurance athletes. The use of multi-joint explosive exercises such as unloaded and loaded jump squats, scissor jumps, bounding, and wall sprints are recommended as they closely resemble running mechanics. Programming factors such as progressive overload, work:rest ratio, training frequency and intensity must be individualised appropriately in order to maximise training adaptations and limit accumulative fatigue. Based on the reviewed studies, elite distance runners are recommended to engage in specific explosive strength training 2-3 days per week for 8-12 weeks in order to improve overall running performance (decreased energy expenditure and oxygen demand at particular velocities).
... In addition to running-specific training, strength training (ST) has been identified by sports and exercise scientists as an effective strategy for enhancing running economy and performance in middle-and long-distance runners [7,8] while also reducing injury risk [9][10][11][12][13][14][15][16]. ST can be defined as the systematic and organized use of exercises in which the body, through muscular actions, works against a certain resistance with the goal of maintaining or optimizing muscular strength. ...
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Despite strength training (ST) being well characterized by professional runners, little is known about the inclusion of ST models for recreational runners. Thus, the present study aimed to investigate the presence of ST in the training practices of recreational runners, with a focus on understanding its characteristics and the motivations of recreational athletes for including ST in their routines. To this end, 801 recreational runners (493 male and 308 female) completed a structured questionnaire regarding their training habits, the inclusion of ST, and its characteristics, concerning the type of ST, training volume, and the reasons for including ST in their training programs. To assess the possible associations between categorical variables, data were analyzed using the chi-square test for independent samples. Approximately 625 runners (78.1%) reported that they included ST in their training routine, with a statistically significant difference between the sexes (men: 73.5% vs. women: 85.4%; X2 = 14.09; p = 0.01). Traditional strength training (TST) was the predominant type of ST included (78.5%), with most participants performing 2–4 sets and 8–12 repetitions per set at a frequency of 3–4 sessions per week. The importance of ST was primarily attributed to performance improvement (85%). The results suggest that recreational runners incorporate different types of ST into their training routines, with TST being the predominant type perceived by runners as a valuable asset for improving running performance.
... Compared to RT, PT can be relatively easily implemented and is suggested to decrease oxygen cost during running by enhancing the ability to utilize elastic energy, consequently contributing to improvements in running performance (Barnes & Kilding, 2015;Turner et al., 2003). Indeed, a previous study recruiting mostly young recreational runners found that the relative changes in the drop jump index (jump height divided by ground contact time) induced by jump rope training were associated with changes in a 3 km running time (Garcia-Pinillos et al., 2020). ...
Article
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The effects of plyometric training (PT) versus resistance training (RT) on running economy and performance are unclear, especially in middle‐aged recreational runners. We examined (1) the efficacy of PT versus RT on running economy and performance in middle‐aged recreational runners and (2) the relationships between the main training outcomes. Twenty middle‐aged recreational runners were randomly allocated to a PT or RT group (n = 10/group). Training was conducted twice/week for 10 weeks combined with daily running. PT included the countermovement jump (CMJ), rebound jump, hurdle hop, and drop jump. RT consisted of leg press, leg curl, and calf raise with 50%–90% of one‐repetition maximum (1RM). Before and after the intervention, 1RM of the three lifting tasks, CMJ and drop jump performances, oxygen cost at 8–12 km/h, and 5 km running time were assessed. PT enhanced 1RM of leg curl only (8.5% and p = 0.007), whereas RT increased 1RM of the three lifting tasks (19.0%–21.1% and p < 0.001). Both groups improved CMJ height (6.4%–8.3% and p = 0.016) and drop jump performance (height: 9.7%–19.4%, p = 0.005, height/contact time: 11.4%–26.3% and p = 0.009) and oxygen cost regardless of running velocity (2.0% and p = 0.001) without significant group differences. However, neither group changed the 5‐km running time (p ≥ 0.259). A significant correlation was found between the changes in calf raise 1RM and oxygen cost (r = −0.477 and p = 0.046) but not between the other measured variables. These results suggest that for middle‐aged recreational runners, PT and RT can similarly improve running economy albeit not necessarily the 5‐km running time, and enhancing plantarflexion strength may particularly contribute to improving running economy.
... A key component of the swiming' record is the ability to store and recover elastic energy from eccentric contraction (23). Several studies have shown the improvement of swiming record as a result of various types of training (24,25). The positive effect of resistance training leads to an increase in the stiffness of the lower body muscles-tendon, the degree of nerve input to the muscle, an increase in muscle strength and elastic return, and an improvement in the coordination of the motor unit (24,26). ...
Article
Resistance training is one of the training methods that leads to muscle growth, functional improvement and injury prevention for athletes. The aim of the present study was to investigate the effect of twelve weeks dry-land resistance training improving swimmers records. The Present study was semi-experimental. The implementation of the present study, 60 young swimmers were selected and randomly divided into two training and control groups. The exercise group performed resistance exercises for twelve weeks. Absolute power, relative power, lower limb power and 100m free style record were analyzed. Multivariate analysis of variance (MANCOVA) test was used to compare the pre-test and post-test of two groups. Also, in order to compare the post-test of two groups, the correlated t-test was used. Paired t-test was also used to compare the pre-test and post-test of the training group to obtain the effect of resistance training. All statistical tests were performed in SPSS version 26. The results showed that exercise group that performed resistance exercises with weight s for twelve weeks had a significant increase compared to the control group. Also, the factors of absolute strength, relative strength, lower limb strength and telemetry of limbs had a significant increase. In addition, the athletes in the training group had lower sprint records. Resistance training increases hypertrophy in muscles and increases power in swimers. Possibly, increasing the absolute and relative strength of the lower limb muscles can affect the anaerobic system and improve the swimming record. However, more research is needed on the volume and intensity of swimmers' resistance training.
... Notably, these enhancements occurred without notable changes in the maximum volume of oxygen consumed per unit time (VO2 max). [16] Likewise, in proficient male middle and long-distance runners, PT led to improved velocities, with increments of 5.7% and 4.1%, respectively, following PT regimens lasting 6 and 9 weeks, respectively. [17] Plyometrics training generally improves jumping ability, linear sprint speed, and change of direction, balance, and strength. ...
Article
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Exercises that involve plyometrics are typically broken up into a stretch-shortening cycle with three phases: an eccentric phase (rapid muscle lengthening), an amortization phase (short resting interval), and a concentric phase (explosive muscle shortening). How quickly an athlete transitions from the eccentric to the concentric phase is a measure of his power. Plyometric training (PT) affects the neuromuscular components of the body for maximum contraction of muscle in minimum time. Soccer is a multidimensional sport and requires various strength training, endurance training, power and agility training, and soccer tactical training. Considering all facts, PT has got a strong tendency to develop cardiovascular and neuromuscular fitness. PT improves VO2 max, explosive strength, linear sprint speed, effective kicking, endurance, agility, soccer skills, and vertical jump ability in athletes of any age. PT improves tendon strengthening and increases muscle elasticity, which results in avoiding injuries.
... Many studies have already proved the benefits of adding heavy or plyometric strength training programs on performance and running economy [17][18][19]23,33,34], untrained endurance runners should preferably follow a maximal-strength-oriented program to enhance maximal force, power, and reactive-strength capabilities, which will lead to an improvement in running economy. This differs from well-trained endurance runners with high-force capabilities who should focus on specific explosive and reactive-strength training to improve performance [24]. ...
Article
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Background: Running-related injuries (RRI) are common in novice runners. Reducing early training running volume with strengthening activities may improve RRI without impeding running performance. Objectives: 1. Gather feasibility data for a randomized, controlled trial comparing a strengthening-based program to a conventional running program; 2. Assess RRI; and 3. Assess running performance. Methods: Seventy-four university students (38 females, 21 ± 2.3 years, 68.2 ± 10.8 kg, BMI: 22.6 ± 2.97), all novice runners, were randomized in two groups, i.e., a strengthening and running group (INT) and a running group (CON). The completed sessions, RRI, dropout, and maximal aerobic speed were recorded through an online application. Results: The INT group had 52.6% attrition, while the CON group had 41.7%. The INT group had 56.6% adherence, while the CON group had 45.7%. The Chi-square test showed no significant difference in RRI incidence across groups (CHI2 = 2.958, p value = 0.08). A two-way ANOVA showed no significant difference in maximal aerobic speed across groups (p = 0.822) or before and after training (p = 0.304). Conclusions: This pilot study confirmed the feasibility of this randomized, controlled trial with a needed sample size of 194. However, novice runners had greater attrition rates when starting. Based on those limited data, strengthening activities that replaced running volume did not improve RRI or maximal aerobic speed.
... En los últimos años el entrenamiento de fuerza en la carrera de medio fondo y fondo ha sufrido un gran auge y un gran número de entrenadores han empezado a incluirlo en sus planificaciones. El objetivo de este tipo de entrenamiento es que la musculatura del atleta se vuelva más fuerte, rápida y potente para que el gesto de carrera sea más efectivo y económico (Turner et al., 2003). Las adaptaciones que se producen en el organismo gracias al entrenamiento de fuerza, no solo son físicas sino también a nivel neuromuscular, mejorando el ciclo de acortamiento estiramiento, favoreciendo el reclutamiento y sincronización de las unidades motrices, lo que supone una mayor rigidez músculo-tendinosa o stiffness y por ende una reducción del tiempo de contacto al correr (Mikkola et al., 2007;Mikkola et al., 2011). ...
Thesis
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El propósito de este trabajo ha sido realizar una serie de test físicos para valorar la estabilidad y fuerza en la cadera junto con un estudio biomecánico a 7 atletas de medio fondo y fondo (5 hombres y 2 mujeres) de nivel competitivo, para detectar posibles desequilibrios musculares y riesgo lesivo. Antes de comenzar el estudio se tomaron datos antropométricos de los participantes y se les pidió que rellenaran una encuesta con sus datos personales. Tras ello se realizaron los test físicos de (i.e., Fuerza Isométrica de core, Trendelenburg, Y-Balance y Abducción-Aducción isométrica máxima de cadera) y acto seguido un análisis biomecánico en 2 dimensiones donde se analizaron 3 variables (i.e., basculación de cadera, flexión de rodilla y ventana de rodilla). Los resultados de los test físicos informaron de algunas deficiencias de fuerza en la musculatura de la cadera. El principal desequilibrio muscular encontrado fue la basculación excesiva de la cadera en 6 de 7 participantes. En conclusión, se ha observado que todos los test utilizados son válidos para valorar la estabilidad de cadera pero algunos muestran resultados más acordes a las descompensaciones encontradas en el estudio biomecánico como es el de Abducción-Aducción isométrica máxima de cadera.
... The results of this MA showed that highly trained athletes improved more than recreational athletes (ES =0.94 vs. ES =0.45). This could be explained because PJT is well tolerated by highlevel athletes (Turner, Owings, & Schwane, 2003) and not so much by lower-level runners (Pellegrino, et al., 2016), which could be due to a minimum of strength needed to start a PJT program as suggested by current concepts (Davies, et al., 2015). Thus, the low training level of recreational athletes, added to the high-impact exercises, could be too aggressive for people without previous experience. ...
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Running economy (RE) has a strong relationship with distance running performance and is defined as the energy demand for a given velocity. Plyometric jump training may improve RE. The present study aimed to assess the effects of plyometric jump training on endurance runners’ running economy and to estimate the effectiveness of program duration, training frequency, total sessions, age, training status and velocity. A literature search was performed using PubMed/MEDLINE, Web of Science, and SCOPUS databases. Subgroup and single training factor analyses of program duration, frequency, total sessions, chronological age, training status, and running velocity were performed. A random-effects model for meta-analyses was used. Eighteen studies were selected for the systematic review and 10 for the meta-analysis. A trivial effect was noted for plyometric jump training on running economy (ES=0.19). However, plyometric jump training combined with resistance training revealed a large effect on running economy (ES=1.34). Greater running economy improvements were noted after training interventions with >15 total sessions (ES=1.00), >7 weeks (ES=0.95) and >2 days/week (ES=0.89). The youngest (ES=0.95) and highly trained participants (ES=0.94) with faster velocities (ES=0.95) obtained better results. Our findings highlight the effect of plyometric jump training that may improve running economy, particularly in combination with resistance training, after longer-term interventions (i.e., >15 total sessions, >7 weeks), with greater frequency, and among younger and more highly trained runners, especially during running at higher competitive velocities.
... So, it is used in physical training to develop the qualities of maximal strength, fast power and explosive power of athletes with obvious effects, and it has become a common training method for lower limb strength training. It has been found that plyometric training can increase the stiffness of muscle tendons and improve the economy of movement of athletes thus improving their competitive performance, but no signi cant changes in lactate threshold and maximal oxygen uptake occurred in athletes after training [41]. It has also been found that weight-bearing plyometric training can signi cantly increase peak hip and ankle moments, peak joint power, joint stiffness, and thus high lower limb muscle strength and explosive power, as well as improve neuromuscular adaptations by reducing hip antagonist muscle activation, and this type of training method was found to be well suited for competitive events [42]. ...
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The objective was to investigate the effect of lower limb muscle isometric strength on speed skating specialized characteristics in elite female speed skaters. Three China speed skaters were subjects (mean age 18.0 ± 1.4) with a mean best score (4'18.9). The isometric mid-thigh pull (IMTP) method was used to test peak force (PF), relative peak force (RPF), rate of force development (RFD), and impulse (IMP) of the lower limb muscles from 0-250ms in June 2021 at the national training base in Qinhuangdao, China. It was concluded that the force-time curves of the athletes' isometric mid-thigh pull (IMTP) exhibited varying elevated and decaying time distribution characteristics. Combined with the skating characteristics of athletes in 3000m Competition, it was found that peak force (PF) and relative peak force (RPF) are important factors affecting average skating speed, rate of change of speed, starting speed, maximum speed and speed endurance. Therefore, the IMTP test can be used as an effective method for preliminary assessment of specific strength and skating ability in the early training of speed skaters while providing effective data support for individualized lower limb strength training and specific technical training.
... The understanding of individual athlete's reactions to different types of training is crucial to remove physiological factors limiting endurance performance [4]. From the essential training variables, exercise intensity and its distribution are probably the most critical and the most heavily debated [3]. ...
... Plyometric training often involves skipping, jumping, and hopping [23]. These exercises have been shown to improve jumping ability [24], sprinting [25], and running economy [26]. However, in addition to plyometric workouts for the lower extremities, the development of upper extremity exercises has been ongoing, and related benefits have been seen, such as improved tennis maximal serve speed and throwing velocity of baseball players [27,28]. ...
Article
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Objective: We aimed to meta-analyze the effects of combined upper and lower limb plyometric training (ULLPT) on physical fitness attributes in athletes. Methods: A systematic literature search was conducted in Web of Science, SPORTDiscus, PubMed, and SCOPUS, for up to 13 August 2022. Controlled studies with baseline and follow-up measures were included if they examined the effects of ULLPT on at least one measure of physical fitness indices in athletes. A random effects meta-analysis was performed using the Comprehensive Meta-Analysis software. Results: Fifteen moderate-to-high-quality studies with 523 participants aged 12–22.4 years were included in the analyses. Small to large (ES = 0.42–1.66; p = 0.004 to <0.001) effects were noted for upper and lower body muscle power, linear sprint speed, upper and lower body muscle strength, agility, and flexibility, while no significant effects on static and dynamic balance were noted (ES = 0.44–0.10; all p > 0.05). Athletes’ sex, age, and training program variables had no modulator role on the effects of ULLPT in available data sets. Conclusions: ULLPT induces distinct neuro-muscular adaptations in the upper and lower body musculature and is an efficient method for enhancing athletes’ physical fitness
... As a previous study has shown that the maximum adaptive capacity of RE occurs within 4-6 weeks of strength training (Turner et al., 2003), our study adopted parallel randomized controlled trials using a 6-week training program. Subjects were randomly assigned to an intervention or control group while pretest and post-tests were performed to analyze the change in RE and jumping performance. ...
Article
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The study aimed to investigate the effect of flywheel accentuated eccentric loading (AEL) training on the running economy (RE) of young male well-trained distance runners. Twenty-two runners participated and were randomly assigned to the flywheel (FG, n = 12) and the control group (CG, n = 10). Traditional endurance training was performed in both groups three times a week for 6-week, while traditional resistance and flywheel AEL training was added to the CG and FG respectively. Subjects performed the incremental exercise test, squat jump, and countermovement jump (CMJ) before and after training. The results showed that 1) the RE at 65% of peak oxygen consumption (VO2peak), 75% VO2peak, and 85% VO2peak improved significantly after 6 weeks of training (p < 0.01, Effect size (ES) = 0.76; p < 0.01, ES = 1.04; p < 0.01, ES = 1.85) in FG, and the RE of 85% VO2peak in FG was significantly lower than CG (p < 0.05, ES = 0.30); 2) in post-training, both squat jump (p < 0.01, ES = 0.73) and CMJ (p < 0.01, ES = 1.15) performance, eccentric utilization ratio (p < 0.04, ES = 0.44), the rate of force development (RFD) of squat jump (p < 0.05, ES = 0.46), and CMJRFD (p < 0.01, ES = 0.66) were significantly improved in FG. And there are no significant differents in CG group because it was maintain training for our participants. Our findings showed that 1) flywheel AEL training improves the muscles’ explosive strength and other neuromuscular functions, and improves the athlete’s running economy under 65%, 75%, and 85% VO2peak, which potentially increases endurance performance. 2) Flywheel AEL training can improve the height, RFD, and the eccentric utilization ratio of squat jump and CMJ, and other lower limb elastic potential energy indicators of the young male, well-trained distance runners.
... Namun tidak semua studi menemukan bahwa PT mampu meningkatkan VJ. Perempuan dari lingkungan perguruan tinggi (Vescovi, Canavan, & Hasson, 2008) dan seorang atlet lari laki-laki (Turner, Owings, & Schwane, 2003) tidak menunjukkan peningkatan VJ dengan perlakuan selama 6 Minggu. Dari sini dapat disimpulkan bahwa perlakuan LP selama 6 Minggu masih belum bisa memberikan dampak yang menunjukkan peningkatan VJ. ...
... Plyometric training i.e., a jump-based strength training method is a commonly used training strategy to increase neuromuscular strength through the stretch-shortening cycle (SSC) in muscle actions ( Ghosh & Biswas, 2020;Markovic & Mikulic, 2010;Ramírez-Campillo et al., 2013) that may positively affect the aerobic performance factors (Conley & Krahenbuhl, 1980), and increases the RSI simultaneously (Paavolainen et al., 1999). A previous study reported that after 6-weeks of plyometric training recreational runners improved their running economy (Turner et al., 2003). Moreover, the running economy can be increased independently by the changes in VO 2 max in plyometric training (Paavolainen et al., 1999). ...
Article
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Abstract: Background: It is already established that plyometric training is a powerful training means for speed and power development; however, very few studies have attempted to know the impact of Plyometric Training on aerobic capacity so far. Sufficient studies were not found by the researchers on plyometric training in land and aquatic medium with & without weight vests for the development of aerobic capacity. Consequently, it was planned to investigate the impact of plyometric training in land and aquatic medium on aerobic capacity from a comparative standpoint. Purpose: Therefore, the present experimentation was aimed to compare the effectiveness of plyometric training programs for 14 weeks on the aerobic capacity of the athletes conducted in three different conditions in land and aquatic medium. Approach: Forty-eight (N = 48) middle-distance track athletes were finally selected based on simple randomization. The selected participants were divided into four equal groups of strength (n=12) each: i) Land Plyometric Training Group (LPTG) ii) Aquatic Plyometric Training Group (APTG) iii) Weighted Vest Aquatic Plyometric Training Group (APTGWV) and iv) Control Group (CG). The same plyometric training was performed for fourteen weeks on the respective training groups in different conditions on dry land surfaces (without a weighted vest) and aquatic medium (without a weight vest & with a weighted vest). Aerobic capacity in terms of maximum oxygen consumption i.e. VO2max (ml.kg-1.min-1) was measured through Queen’s-College-Step-Test (QCST). To draw a statistical inference on aerobic capacity among the groups in baseline & post-intervention conditions, analysis of covariance (ANCOVA) was used. Tukey's post-hoc LSD test was employed to identify the location of difference among the groups. Statistical inferences were drawn at p<.05 level. Results: Different plyometric training groups improved significantly in comparison to the control group in aerobic capacity. Therefore, plyometric training was found as an effective means of developing aerobic capacity. A significant difference was also observed between the land plyometric training group and the weighted vest aquatic plyometric training group in aerobic capacity. However, the rest of the experimental groups didn’t differ significantly. Conclusions: Plyometric training is not only beneficial for speed and power development but also proved as an effective means for developing aerobic capacity. It is further established that weighted vest aquatic plyometric training is the best one among the training groups for improving the aerobic capacity of the athletes. Normal aquatic plyometric training is equally effective as land Plyometric training for improving aerobic capacity. Key Words: - Aerobic ability; Aerobic fitness; Queen’s College Step Test (QCST); VO2max; Aquatic plyometric training; Weighted vest aquatic plyometric training.
... Increasing lower leg quasi-stiffness and reactive strength through plyometric training enables better utilization of the SSC [11,57]. Interestingly, Turner et al. [58] reported that moderately trained endurance runners improved running economy after 6 weeks of plyometric training; however, there was no improvement in vertical jump performance. This could have been due to the shorter duration of the plyometric training (10-15 min), which was not primarily focused on improving vertical jumping performance. ...
Article
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It is well-accepted that at least a certain amount of resistance exercise (RE) is recommended for most endurance athletes. In this review, we aim to summarize the evidence regarding the effects of RE on running economy, running biomechanics, and running-related injury risk in endurance runners. The evidence robustly shows that lower limb RE is effective for improving running economy and performance, with a combination of strength and plyometric training being recommended to improve RE. Isometric training is also emerging as a possible alternative to implement during periods of high overall training load. Lower limb RE may change some aspects of joint kinematics during running; however, the evidence regarding the effects on kinetics is limited. Lower limb RE may help reduce running-related injury risk, but further evidence is needed.
... Plyometric training is widely used in speed and strength development studies 14 . Studies have shown that plyometric training increases the athlete's sprint 11 , agility 20 , change of direction 21 and running economy 22,23 . The ability of athletes to use eccentric and concentric contraction properties effectively is an important performance criterion in many sports 24,25,26,53,54 . ...
Article
Aim: The aim of the study was determined as the examination of the reactive strength index parameter, which shows the maximal strength and explosive force characteristics of 16-17 age group basketball players determined by isometric test. Method: The basketball branch Xage = 16.50 ± 0.51 years, XHeight = 177.22 ± 8,56 cm, XBW= 73.14 ± 12,43 kg, XBMI= 23.26 ± 3,46 kg / m2, and XBFP = 14.72 ± 5.67% of which 32 are men. In the study, the measurements of the height of the participants were made with Holtain brand stadiometer, body weight and fat percentage ratio measurement with Tanita BC 418 MA, reactive strength index measurement with Opto Jump Next, and maximal strength measurement with Baseline brand leg dynamometers. Pearson test was used to determine the relationship between branch-specific MS and RSI. Results: According to the correlation results, no significant relationship was found between MS and RSI (p>0.05). Conclusions: As a result, it has been determined that basketball players between the ages of 16-17 do less quality work on developing MS and explosive force. Keywords: Basketball, Maximal Strength, Reactive Strength İndex.
... Direct assessment of skeletal muscle ultrastructure has provided evidence of disruption to the normal myofibrillar banding pattern (7-10) after strenuous exercise involving repeated eccentric muscle actions. Accordingly, long-distance running events, and plyometric and resistance training, which may be included in endurance training programs to improve running economy (11)(12)(13), are associated with substantial muscle soreness, inflammation and swelling, increased concentration of creatine kinase (CK) in the plasma, and the loss of muscle function and running economy, which persists for several days (14,15). ...
Article
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Purpose: We tested the hypotheses that a highly cushioned running shoe (HCS) would: 1) improve incremental exercise performance and reduce the oxygen cost (Oc) of submaximal running; and 2) attenuate the deterioration in Oc elicited by muscle damage consequent to a downhill run. Methods: Thirty-two recreationally-active participants completed an incremental treadmill test in a HCS and a control running shoe (CON) for the determination of Oc and maximal performance. Subsequently, participants were pair-matched and randomly assigned to one of the two footwear conditions to perform a moderate-intensity running bout pre- and 48 h post a 30-min downhill run designed to elicit muscle damage. Results: Incremental treadmill test performance was improved (+5.7%; +1:16 min:ss; P < 0.01) in the HCS when assessed in the non-damaged state, relative to CON. This coincided with a significantly lower Oc (-3.2%; -6 ml·kg-1·km-1; P < 0.001) at a range of running speeds and an increase in the speed corresponding to 3 mM blood lactate (+3.2%; +0.4 km·h-1; P < 0.05). As anticipated, the downhill run resulted in significant changes in biochemical, histological, and perceptual markers of muscle damage, and a significant increase in Oc (+5.2%; 10.1 ml·kg-1·km-1) was observed 48 h post. In the presence of muscle damage, Oc was significantly lower in HCS (-4.6%; -10 ml·kg-1·km-1) compared to CON. Conclusions: These results indicate that HCS improved incremental exercise performance and Oc in the absence of muscle damage and show, for the first time, that despite worsening of Oc consequent to muscle damage, improved Oc in HCS is maintained.
... Namun tidak semua studi menemukan bahwa PT mampu meningkatkan VJ. Perempuan dari lingkungan perguruan tinggi (Vescovi, Canavan, & Hasson, 2008) dan seorang atlet lari laki-laki (Turner, Owings, & Schwane, 2003) tidak menunjukkan peningkatan VJ dengan perlakuan selama 6 Minggu. Dari sini dapat disimpulkan bahwa perlakuan LP selama 6 Minggu masih belum bisa memberikan dampak yang menunjukkan peningkatan VJ. ...
... Research examining concurrent strength and endurance training show the largest performance improvements are generated primarily from moderateto-progressively heavy load ST exercises ($80% of 1RM) with 2-3 minutes of rest between each set (10,11,39,62,71,72,(77)(78)(79)83,84,88,90,91,96,99,100). To ensure ST is completed at the correct loads, athletes may undertake 1RM testing for primary exercises regularly. ...
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Concurrent training, commonly acknowledged as a training method where strength and endurance training are completed complementary to each other, is a strategy often implemented in endurance cyclists' and runners' programs to improve physiological determinants of success such as exercise economy. Although concurrent training methods and strategies have been examined to a large extent in endurance cyclists and runners, literature examining optimal concurrent training methods to improve physiological variables in long-distance triathletes is minimal, leaving optimal programming relatively unknown. This practical applications paper identifies and outlines current concepts and considerations regarding concurrent training for long-distance triathletes including mechanisms contributing to improved performance, muscle and movement patterns used, exercise selection, load, velocity of movement, scheduling, frequency, and duration of training. Common misconceptions related to concurrent training are also identified and practical considerations for the application of concurrent training for coaches, athletes, and other professionals to improve all 3 disciplines of triathlon are discussed.
... RE was calculated from the running velocity divided by netVO 2 normalized to individual body mass (m·ml −1 ·kg −1 ) where neṫ VO 2 =VO 2 −restVO 2 , with restVO 2 given by the average over the last minute of a 5 min upright stance measure prior to the submaximal running test. This choice of units for RE have a conceptual advantage that numerical values are directly related to RE (i.e., the larger the numerical value, the better the RE) (Turner et al., 2003). ...
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... The following six exercises were performed for seven weeks: warm-up double-leg vertical jumps with 50% maximal effort; intermittent double-leg vertical power jumps; intermittent single-leg vertical power jumps; vertical springing jumps; split squat jumps; and double-leg springing jumps on an inclined plane. The plyometric exercise program is explained in more detail in Table 1 [18]. ...
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... In contrast, previous literature suggests vertically applied programs typically benefit transitional (10-20 m) and maximal speed phases and vertical jump performance by increasing ground reaction forces, reactive strength, leg stiffness, and decreasing ground contact time (15,36). Although, plyometric training programs that have reported no sprint performance benefits tend to be void of horizontal stimulus and are generally associated with low-intensities (46,52). Thus, more clarity is needed to understand the loading parameters and specific adaptations with respect to training axis, especially because most direction-based investigations are in young populations. ...
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Background The running performance of middle-distance and long-distance runners is determined by factors such as maximal oxygen uptake (VO2max), velocity at VO2max (vVO2max), maximum metabolic steady state (MMSS), running economy, and sprint capacity. Strength training is a proven strategy for improving running performance in endurance runners. However, the effects of different strength training methods on the determinants of running performance are unclear. Objective The aim of this systematic review with meta-analysis was to compare the effect of different strength training methods (e.g., high load, submaximal load, plyometric, combined) on performance (i.e., time trial and time until exhaustion) and its determinants (i.e., VO2max, vVO2max, MMSS, sprint capacity) in middle-distance and long-distance runners. Methods A systematic search was conducted across electronic databases (Web of Science, PubMed, SPORTDiscus, SCOPUS). The search included articles indexed up to November 2022, using various keywords combined with Boolean operators. The eligibility criteria were: (1) middle- and long-distance runners, without restriction on sex or training/competitive level; (2) application of a strength training method for ≥ 3 weeks, including high load training (≥ 80% of one repetition maximum), submaximal load training (40–79% of one repetition maximum), plyometric training, and combined training (i.e., two or more methods); (3) endurance running training control group under no strength training or under strength training with low loads (< 40% of one repetition maximum); (4) running performance, VO2max, vVO2max, MMSS and/or sprint capacity measured before and after a strength training intervention program; (5) randomized and non-randomized controlled studies. The certainty of evidence was assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. A random-effects meta-analysis and moderator analysis were performed using Comprehensive meta-analysis (version 3.3.0.70). Results The certainty of the evidence was very low to moderate. The studies included 324 moderately trained, 272 well trained, and 298 highly trained athletes. The strength training programs were between 6 and 40 weeks duration, with one to four intervention sessions per week. High load and combined training methods induced moderate (effect size = − 0.469, p = 0.029) and large effect (effect size = − 1.035, p = 0.036) on running performance, respectively. While plyometric training was not found to have a significant effect (effect size = − 0.210, p = 0.064). None of the training methods improved VO2max, vVO2max, MMSS, or sprint capacity (all p > 0.072). Moderators related to subject (i.e., sex, age, body mass, height, VO2max, performance level, and strength training experience) and intervention (i.e., weeks, sessions per week and total sessions) characteristics had no effect on running performance variables or its determinants (all p > 0.166). Conclusions Strength training with high loads can improve performance (i.e., time trial, time to exhaustion) in middle-distance and long-distance runners. A greater improvement may be obtained when two or more strength training methods (i.e., high load training, submaximal load training and/or plyometric training) are combined, although with trivial effects on VO2max, vVO2max, MMSS, or sprint capacity.
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Carder, MJ, Scudamore, EM, Savanna, KN, Pribyslavska, V, Bowling, LR, and O'Neal, EK. Retrospective and contemporary predictors of National Collegiate Athletic Association Division I cross-country performance are sex specific. J Strength Cond Res 37(11): 2267–2272, 2023—The purpose of this study was to identify National Collegiate Athletic Association (NCAA) Division I cross-country (XC) performance potential using laboratory-based and field-based parameters and retrospective high school (HS) personal best (PB) data at various distances of current collegiate XC runners. Fifteen female and 17 male NCAA XC runners provided their PB for 5-km (women) and 8-km (men) distances from the previous season. Bivariate correlation and stepwise and hierarchical regression modeling were used to predict XC performance. Single squat jump height and multijump reactive strength index displayed r < 0.27 for both sexes, suggesting lower-body power is a poor predictor of XC performance or masked by other factors of greater importance. Triceps skinfold thickness approached significance ( r = 0.43; p = 0.09) for men but was unrelated to women's performance ( r = −0.05; p = 0.86). HS XC PB neared significance ( r = 0.55, p = 0.054), but no other single or combination of variables reached significance for female runners. Aerobic capacity displayed a moderate to strong relationship ( r = 0.65) for male runners. High school 3,200-m PB for men produced a robust prediction capacity ( r = 0.85; p = 0.005, SEE = ± 0.65 minutes), and predicted 8-km PB within 30 seconds for approximately two-thirds of runners. These outcomes suggest when recruiting HS or transfer athletes, male and female XC runners should not be recruited on the same factors. Women's XC PB is more difficult to predict, but skinfold thickness was statistically the least valuable predictor of all factors.
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A regular endurance training program may elicit different adaptations compared to an isolated training method. In this study, we analyzed the effects of 8 weeks of a regular endurance training program on running economy (RE), particularly neuromuscular and biomechanical parameters, in runners of different athletic abilities. Twenty-four male runners were divided into two groups: well-trained (n=12) and recreational (n=12). Both groups completed a 4-min running bout at 13 and 17 km·h-1, respectively, for the recreational and well-trained group, and a 5-jump plyometric test pre-post intervention. During the training program, participants completed low-intensity continuous sessions, high-intensity interval training sessions, and auxiliary strength training sessions. RE, measured as oxygen cost and energy cost, decreased by 6.15% (p=0.006) and 5.11% (p=0.043), respectively, in the well-trained group. In the recreational group, energy cost of running, respiratory exchange ratio, and leg stiffness decreased by 5.08% (p=0.035), 7.61% (p=0.003), and 10.59% (p=0.017), respectively, while ground contact time increased by 3.34% (p=0.012). The maximum height of the 5-jump plyometric test decreased by 4.55% (p=0.018) in the recreational group. We suggest that 8 weeks of regular endurance training leads to an improvement of ~5% in RE in recreational and well-trained runners with different physiological adaptations between groups and few changes in biomechanical and neuromuscular parameters only in recreational runners.
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Plyometric training (PT) has been shown to have numerous benefits and few harmful effects. This study aimed to compare the effects of PT vs. strength training on muscle strength, sprint, and lower limb functional performance in soccer players. Ninety participants (mean age 22.5 years) were equally and randomly divided into three groups: a plyometric training group (PTG; n = 30), a strength training group (STG; n = 30), and a control group (CG; n = 30). In PTG: bounding, hurdling, and drop jumping exercises were performed. In STG: isometric exercises of knee extension (at 60º knee flexion), quadriceps (in supine), hip adductors (in crook lying), and straight leg raise were performed. In CG: no specific training was given. All interventions were performed for eight weeks. Isometric strength (IS), sprint (ST), and single-leg triple hop (SLTH) tests were outcome measures. The wilcoxon signed ranks test was used for with-in-group analysis, and Kruskal Wallis and Mann–Whitney u tests were used for between-group analyses. In PTG: in comparison to a baseline measurement, IS increased by 8.83% (p < 0.05), ST decreased by 20.14% (p < 0.05), and SLTH increased by 7.78% (p < 0.05). In STG: IS increased by 15.76% (p < 0.05), ST decreased by 30.26% (p < 0.05), and SLTH increased by 12.41% (p < 0.05). In CG: IS increased by 5.72% (p < 0.05), ST decreased by 15.54% (p < 0.05), and SLTH increased by 4.41% (p < 0.05). The greatest improvements were observed in STG, followed by PTG and CG. Strength training was found to be more effective than PT in improving muscle strength, sprint, and lower limb functional performance in male soccer players.
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Running economy is one of the factors contributing running performance. The athlete who use oxygen more economically is more successful. Currently, there is no research on this topic in Azerbaijan. Azerbaijani athletes have not been investigated on running economy before, so this will be the first research in this field in the country. By the end of this research more economical position on the pitch and comparison National Football Players with elite athletes has been identified.
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The effect of compression tights on running economy is unclear. The purpose of this investigation was to assess the influence of compression tights on economy. Following an incremental test to exhaustion to determine aerobic capacity (V̇O2max) and peak running speed (vV̇O2max), twenty-six moderately endurance-trained males (28 ± 7 years; 76.1 ± 8.4 kg; V̇O2max = 54.7 ± 4.8 mL·kg⁻¹·min⁻¹) were allocated to either a 60% (n = 8), 62.5% (n = 9) or 65% vV̇O2max group (n = 9) using block randomisation. Participants ran for 15 min at the allocated vV̇O2max with compression tights and a non-compression control condition in a randomised, counter-balanced order, separated by seven days. Oxygen consumption (V̇O2) and expired carbon dioxide (V̇CO2) was measured to determine economy as caloric unit cost. No difference was observed between conditions for the 60% and 62.5% vV̇O2max groups, however economy was improved with compression at 65% vV̇O2max (P < 0.01). Combined analysis of all participants revealed ΔRE (Δ = control − compression) correlated with relative aerobic capacity (%V̇O2max) (r = 0.50, P < 0.01) but not running speed (r = 0.04, P < 0.84). These data suggest that compression tights influence economy at 65% vV̇O2max or at relative exercise intensities of approximately 75–85%V̇O2max.
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Bu araştırmanın amacı, 16-17 yaş grubu güreşçilerin izometrik test ile belirlenen maksimal kuvveti ve patlayıcı kuvvet özelliklerini gösteren reaktif kuvvet indeksi parametresinin incelenmesi şeklinde belirlenmiştir. Araştırmaya Ankara ilinde çeşitli spor kulüplerinde antrenman yapan güreş branşından (XYaş=16,62±0,49yıl, XBoy=171,08±7,55cm, XVA=69,22±11,08 kg, XVKİ=23,50±2,82 kg/m2, ve XVYY=10,97±3,89 %) 24 erkek gönüllü sporcu katılmıştır. Araştırmada, katılımcıların boy uzunluğu ölçümü stadiometre, vücut ağırlığı ve yağ yüzde oranı ölçümü profesyonel vücut analiz cihazı, reaktif kuvvet indeksi ölçümü Opto Jump Next, maksimal kuvvet ölçümü bacak dinamometresi ile yapılmıştır. Güreşçilerin MK ile RKİ arasındaki ilişkiyi belirlemek için pearson testi uygulanmıştır. Korelasyon sonuçlarına göre, güreşçilerin MK ile RKİ arasında anlamlı bir ilişki tespit edilmemiştir. Sonuç olarak, bu araştırma; 16-17 yaş aralığında olan güreşçilerin maksimal kuvvetleri ile patlayıcı kuvvetlerinin gelişim düzeylerinde farklılık olduğunu göstermiştir.
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Back Ground: Trunk performance is important for functional outcomes and also a predictor for activities of daily living after stroke. Swiss ball training is superior to ground-based exercise in its ability to recruit trunk muscles by increasing its demand and trunk balance on healthy individuals and athletes. However retrievable literature evidence for Swiss ball training on trunk performance is not available in the stroke population. Objective: To evaluate trunk performance on Swiss ball training after stroke. Design: An assessor-blinded,quasi-experimental study design. Setting: Physiotherapy Department of Kasturba Medical College and hospital, Mangalore, Manipal University. Participants: Twelve subjects having first-ever unilateral stroke who can able to sit on a stable surface independently for one minute were recruited. Intervention: In addition to conventional physiotherapy all the study subjects received 10 hours of individual and supervised trunk exercises on Swiss ball; 45 minutes with adequate rest periods 10-15 minutes, 6 times a week, for 3 weeks. Outcome Measurement: Trunk performance was evaluated by the Trunk Impairment Scale (TIS) by Verheyden. Results: Post-intervention the study group has shown an improvement in TIS score. A significant improvement was seen in dynamic balance and coordination subscales and also in the total score (p-value <0.05) of TIS. Conclusion: Training on Swiss ball improves trunk performance after stroke.
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Background The aim of this study is to conduct a systematic review with meta-analysis to explore the effects of plyometric jump training (PJT) on the physical fitness of individual sport athletes (ISA). Methods Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched through PubMed, Web of Science, and SCOPUS electronic databases. We included controlled studies that incorporated a PJT intervention among ISA (with no restriction for age or sex), that included a pre-to-post intervention assessment of physical fitness (e.g., sprint; jump). From the included studies, relevant data (e.g., PJT and participants characteristics) was extracted. We assessed the methodological quality of the included studies using the PEDro scale. Using a random-effects model, meta-analyses for a given outcome was conducted. Means and standard deviations for a measure of pre-post-intervention physical fitness from the PJT and control groups were converted to Hedges’ g effect size (ES). Heterogeneity was assessed using the I ² statistic. The risk of bias was explored using the extended Egger’s test. The statistical significance threshold was set at p < 0.05. Moderator analyses were conducted according to the sex, age and sport background of the athletes. Results Twenty-six studies of moderate-high methodological quality were included (total participants, n = 667). Compared to controls, PJT improved vertical jump (ES = 0.49; p < 0.001; I = 0.0%), linear sprint (ES = 0.23; p = 0.032; I ² = 10.9%), maximal strength (ES = 0.50; p < 0.001; I ² = 0.0%) and endurance performance (ES = 0.30; p = 0.028; I ² = 11.1%). No significant effect was noted for sprint with change of direction (ES = 0.34; p = 0.205; I ² = 70.9%). Athlete’s sex, age and sport background had no modulator role on the effect of PJT on vertical jump, linear sprint, maximal strength and endurance performance. Among the included studies, none reported adverse effects related to the PJT intervention. Conclusions PJT induces small improvements on ISA physical fitness, including jumping, sprinting speed, strength and endurance.
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This study determined the effects of a 10-week strength training program on running economy in 12 female distance runners who were randomly assigned to either an endurance and strength training program (ES) or endurance training only (E). Training for both groups consisted of steady-state endurance running 4 to 5 days a week, 20 to 30 miles each week. The ES undertook additional weight training 3 days a week. Subjects were tested pre and post for [latin capital V with dot above]O2, max, treadmill running economy, body composition, and strength. A repeated-measures ANOVA was used to determine significant differences between and within groups. The endurance and strength training program resulted in significant increases in strength (p < 0.05) for the ES in both upper (24.4%) and lower body (33.8%) lifts. There were no differences in treadmill [latin capital V with dot above]O2, max and body composition in either group. Running economy improved significantly in the ES group, but no significant changes were observed in the E group. The findings suggest that strength training, when added to an endurance training program, improves running economy and has little or no impact on [latin capital V with dot above]O2, max or body composition in trained female distance runners. (C) 1997 National Strength and Conditioning Association
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This study was undertaken to determine the response of V˙\dot V O2 max and of running performance (805 and 3218 m) to the onset of training in untrained individuals and to an increase in the volume and intensity of training in well trained individuals. In series A, V˙\dot V O2 max and performances of 12 previously untrained individuals were determined before and after 4 and 8 weeks of training. In series B, performances, V˙\dot V O2 max and V˙\dot V O2 submax of 15 previously well trained runners were determined before and after 4 and 8 weeks of controlled training. In series A, V˙\dot V O2 max increased during the first 4 weeks of training but failed to increase further even in the presence of an increased training load (80 total km for the first 4 weeks, 130 total km for the second 4 weeks). Running performances improved throughout the training period. In series B, neither V˙\dot V O2 max nor V˙\dot V O2 submax changed but running performance improved throughout the experimental period. The results indicated that not all of the improvement in running performance subsequent to training is attributable to changes in V˙\dot V O2 max. Further the results indicate that changes in running economy are not a likely explanation for performance improvement among previously well trained runners. It is suggested that physiological adaptations not integrated in the test of V˙\dot V O2 max, or improvement in pacing contribute to training induced improvements in running performance.
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The purpose of the study was to determine the relationship between running economy and distance running performance in highly trained and experienced distance runners of comparable ability. Oxygen uptake (Vo2) during steady-state and maximal aerobic power (Vo2max) were measured during treadmill running using the open-circuit method. Distance running performance was determined in a nationally prominent 10 km race; all subjects (12 males) placed among the top 19 finishers. The subjects averaged 32.1 min on the 10 km run, 71.7 ml.kg-1.min-1 for Vo2max, and 44.7, 50.3, and 55.9 ml.kg-1.min-1 for steady-state Vo2 at three running paces (241, 268, and 295 m.min-1). The relationship between Vo2max and distance running performance was r = -0.12 (p = 0.35). The relationship between steady-state Vo2 at 241, 268 and 295 m.min-1 and 10 km time were r = 0.83, 0.82, and 0.79 (p < 0.01), respectively. Within this elite cluster of finishers, 65.4% of the variation observed in race performance time on the 10 km run could be explained by variation in running economy. It was concluded that among highly trained and experienced runners of comparable ability and similar Vo2max, running economy accounts for a large and significant amount of the variation observed in performance on a 10 km race.
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Plyometric training has become a popular training and rehabilitation tool. The purpose of this study was to compare the effects of plyometric and isokinetic concentric/eccentric training of the shoulder internal rotators. Female subjects (N = 78) were randomly assigned to three groups: control, isokinetic training, and plyometric training. Pre-/posttesting measurements included: 1) concentric/eccentric isokinetic power measurements of the shoulder internal rotators at 60 degrees/sec, 180 degrees/sec, and 240 degrees/sec; 2) kinesthetic measurements of shoulder internal rotation, external rotation < 45 degrees, and external rotation > 45 degrees; and 3) a softball distance test. Both groups trained twice a week for 8 weeks. Power and kinesthetic data were analyzed using multiple analyses of variance with repeated measures. A one-way analysis of variance was performed on the softball throw data. No significant (p < .05) pre-/posttest differences were found with kinesthetic testing or the softball throw. Pre-/postpower differences were significantly greater for the isokinetic group at 60 degrees/sec eccentric, 120 degrees/sec concentric and eccentric, and 240 degrees/sec concentric and eccentric. Isokinetic training of the shoulder internal rotators increases isokinetic power, but neither isokinetic nor plyometric training resulted in a functional improvement with the softball throw.
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To investigate the effects of simultaneous explosive-strength and endurance training on physical performance characteristics, 10 experimental (E) and 8 control (C) endurance athletes trained for 9 wk. The total training volume was kept the same in both groups, but 32% of training in E and 3% in C was replaced by explosive-type strength training. A 5-km time trial (5K), running economy (RE), maximal 20-m speed (V20 m), and 5-jump (5J) tests were measured on a track. Maximal anaerobic (MART) and aerobic treadmill running tests were used to determine maximal velocity in the MART (VMART) and maximal oxygen uptake (VO2 max). The 5K time, RE, and VMART improved (P < 0.05) in E, but no changes were observed in C. V20 m and 5J increased in E (P < 0.01) and decreased in C (P < 0.05). VO2 max increased in C (P < 0.05), but no changes were observed in E. In the pooled data, the changes in the 5K velocity during 9 wk of training correlated (P < 0.05) with the changes in RE [O2 uptake (r = -0.54)] and VMART (r = 0.55). In conclusion, the present simultaneous explosive-strength and endurance training improved the 5K time in well-trained endurance athletes without changes in their VO2 max. This improvement was due to improved neuromuscular characteristics that were transferred into improved VMART and running economy.
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By utilizing a special 'sledge' apparatus which was connected to a force-plate, eccentric and concentric exercises were isolated so that only one form of contraction of the leg extensor muscles (either eccentric or concentric) was performed in a single exercise set of 80 contractions. A total of four submaximal energy levels were investigated in both exercise types and the peak knee angular velocities ranged from 14 rad x s -1 to 28 rad x s -1, respectively during the lowest, and highest exercise levels. The net mechanical efficiency was computed so that the force-plate record gave the mechanical work output, and the analysis of the expired air during the work and recovery phases gave the energy expenditure over that in the resting conditions. The results indicate that under all exercise conditions the net mechanical efficiency of the concentric exercise stayed relatively constant with a mean of 19.4±2.0%. In eccentric exercise the corresponding value was 85.2±36.8%, but varied greatly, the highest individual value being 190.6%. In the whole group of six subjects the net mechanical effciency of eccentric exercise was significantly (P<.01) related to the peak knee angular velocity, indicating higher efficiency values with increased stretch velocities of the knee extensor muscles. The results suggest that while no set value can be given to the efficiency of negative work, the mechanical behavior of muscle during eccentric contraction results in performance of high mechanical work with low energy expenditure.
Article
Forty-eight volunteer males were randomly assigned to one of three groups. Group I trained with isokinetic exercises, Group II trained with plyometric exercises, and Group III was the control. Subjects in the training groups trained three times per week for 8 weeks. The isokinetic group performed three sets of 10 repetitions per set of leg presses each training session. The plyometric group performed three sets of 10 repetitions per set of depth jumps from a height of 34 inches, with added resistance beginning with weeks 3, 5, and 7 of 10, 15, and 20 pounds, respectively. Prior to and at the end of the training period, all subjects were given a vertical jump-and-reach test. Covariance analysis was used to compare posttest scores with the effect of pretest differences removed. Results showed both training groups improved significantly in vertical jump capacity; however, no significant difference existed between training groups.
Article
The question, if muscles can absorb and temporarily store mechanical energy in the form of elastic energy for later re-use, was studied by having subjects perform maximal vertical jumps on a registering force-platform. The jumps were performed 1) from a semi-squatting position, 2) after a natural counter-movement from a standing position, or 3) in continuation of jumps down from heights of 0.23, 0.40, or 0.69 m. The heights of the jumps were calculated from the registered flight times. The maximum energy level, Eneg, of the jumpers prior to the upward movement in the jump, was considered to be zero in condition 1. In condition 2 it was calculated from the force-time record of the force-platform; and in condition 3 it was calculated from the height of the downward jump and the weight of the subject. The maximum energy level after take-off, Ep0s, was calculated from the height of the jump and the jumper's weight. It was found that the height of the jump and Epos increased with increasing amounts of Eneg, up to a certain level (jumping down from 0.40 m). The gains in Epos over that in condition 1, were expressed as a percentage of Eneg and found to be 22.9 % in condition 2, and 13.2, 10.5, and 3.3 % in the three situations of condition 3. It is suggested that the elastic energy is stored in the active muscles, and it is demonstrated that the muscles of the legs are activated in the downward jumps before contact with the platform is established.
Article
The purpose of this study was to compare the oxygen cost of running as it relates to speed of running among the following four groups: trained male distance runners, trained female distance runners, untrained but active men and women. Each subject was given a series of treadmill tests during which Vo2 was measured at submaximal work loads. The linear regression equation was utilized to compute the relationship between Vo2 and running speed for each groups. The results indicated that the rate of increase in Vo2 for a given increase in running speed could be represented as a straight line and was the same for all groups (P greater than .05). The trained male runners had a significantly lower Vo2 (P less than .05) than those of the other three groups at any measured speed. The trained females and untrained males had significantly lower Vo2s than the untrained females (P less than .05) at any of the given range of speeds. No significant differences were observed between the untrained mean and trained women (P greater than .05). It was concluded that there were differences in the oxygen cost of running not only between the trained and untrained groups but also between males and females.
Article
The study of running economy has important performance implications for the long-distance runner and may provide insight into mechanisms underlying economical human locomotion. Physiological aspects of running economy discussed in this paper include intraindividual variability, body temperature, heart rate, ventilation, muscle fiber type, gender, air and wind resistance, altitude, fatigue, and training. The lack of consensus evident in the literature regarding many of these variables and their influence on economy supports the use of expanded sample sizes featuring both genders, standard testing conditions, and cross- and interdisciplinary approaches to help explain group economy differences observed in descriptive and experimental paradigms and to extend the generalizability of research findings.
Article
The purposes of this investigation were to document the changes in stride length of college-age male novice runners (n = 13) who were allowed of freely choose their stride length throughout a 7-week training period (FCSL), and to compare subsequent changes in running economy to those observed in a similar group of runners (n = 13) that ran for 7 weeks with constant stride lengths equivalent to their initially chosen stride lengths (CSL). Subjects trained 3 days per week for approximately 7 weeks (22 training bouts). Each training bout consisted of a minute warmup (60% VO2max) and a 15-minute run at a speed equivalent to 80% of the subjects' initial VO2max. Absolute stride length (ASL), heart rate (HR), and ratings of perceived exertion (RPE) were measured during the 12th and 20th minute of exercise. Relative and absolute submaximal VO2 were measured during the 4th and 22nd training bout. No significant differences in percent change in ASL were found between the groups or across the weeks of training at the 12th or 20th minute of exercise; however, there was a significant difference (p less than or equal to .05) between the groups during the 4th week of training. No significant differences were found between the groups in relative or absolute submaximal VO2. Relative submaximal VO2 at the 12th minute of exercise decreased significantly following the training period in both the FCSL (-3.38%) and CSL (-4.32%) groups. Absolute submaximal VO2 did not change significantly following the training period.(ABSTRACT TRUNCATED AT 250 WORDS)
Article
The mechanical efficiency of the leg extensor musculature of men and women was examined with a special “sledge ergometer”. The subjects (ten males and ten females) performed (a) pure positive work, (b) pure negative work and (c) a combination of negative and positive work (strech-shortening cycle). The mechanical efficiency of pure positive work was on average 19.8±1.2% for female subjects and 17.4±1.2% for male subjects (t=4.12, P<0.001), although the work intensity was equal in both groups. The mechanical efficiency of pure negative work was slightly lower in women than in men (59.3±14.4% vs 75.6±29.3%). The mechanical efficiency of positive work (η+) in a stretch-shortening cycle exercise was 38.1±6.8% in men and 35.5±6.9% in women. The utilization of prestretch was better for female subjects at low prestretch levels, whereas males showed greater potentiation of elastic energy at higher prestretch levels. Regarding absolute W el (work due to elasticity) values, male subjects showed greater (P<0.001) values than females (189±44 J vs 115±36 J, respectively). Fundamental differences in neuromuscular functions in men and women might cause the differences in the results obtained.
Article
The effect of plyometric training on vertical jump was determined in male high school basketball players (n=26). Players were randomly assigned to a training group or a control group. The training group performed 3 sets of 10 depth jumps 3 days/week for 12 weeks. The control group performed only the regular basketball training. The plyometric group improved in vertical jump with arm assistance significantly (p<.05) more than the control group. The two groups were not significantly (p>.05) different in vertical jump without arm assistance. In the plyometric group, 57% of the vertical jump gain was due to jumping skill improvement, and 43% was due to strength gain. Therefore, plyometric training appears to enhance the coordination of the arms with strength development of the legs and provides a convenient in-season training method.
Article
3 subjects ran on the treadmill (10 km/h) against varying horizontal impeding forces. One subject was further studied during the same kind of walking and bicycling on the treadmill, and during work consisting in lowering and lifting the body by flexing and extending the legs from a standing or sitting position at varying frequencies, with or without rebound in the deepest position. Workpower (W kcal/min), and the corresponding steady state metabolic rate (E kcal/min, Douglas bag method) were measured. Apparent efficiency (N) was calculated as Δẁ/ΔÈ× 100 %. During load running N was 53.8, 37.6 and 41.2 %, respectively, in the 3 subjects. In the subject more extensively studied N was: running 53.8, walking 32.3, bicycling 25.1, knee-flexions (deep or half) with rebound 39.4 or 41.0, without rebound 26.1 or 21.9 %. These variations in N % were explained in accordance with the possibilities for re-using the energy, absorbed and stored in the muscles as elastic energy during a phase of negative exercise, in a subsequent phase of positive exercise. The condition of this is that the positive phase follows immediately after the negative. A calculation showed that during running 35–53 % of the energy absorbed during the negative phase was re-used. Corresponding figures for walking and rebounding knee-extensions were 23 % and 34 %, respectively, while in bicycling and knee-extensions without rebound all of the negative work degenerated into heat.
Article
To determine the effects of prescribed training programs on 5 physical fitness test items, each of 50 high school boys participated for 10 wk. in one of three programs (wrestling, softball, and plyometrics; weight training; and weight training and plyometrics). (a) On the sit-ups, 40-yd. dash, vertical jump, and pull-ups, each group improved significantly from pre- to posttest. (b) On the shuttle run, none of the groups improved significantly from pre- to posttest. (c) On the vertical jump, groups had a significant effect, but the interaction was nonsignificant. No effects were significant.
Article
This study was performed to determine which of three theoretically optimal resistance training modalities resulted in the greatest enhancement in the performance of a series of dynamic athletic activities. The three training modalities included 1) traditional weight training, 2) plyometric training, and 3) explosive weight training at the load that maximized mechanical power output. Sixty-four previously trained subjects were randomly allocated to four groups that included the above three training modalities and a control group. The experimental groups trained for 10 wk performing either heavy squat lifts, depth jumps, or weighted squat jumps. All subjects were tested prior to training, after 5 wk of training and at the completion of the training period. The test items included 1) 30-m sprint, 2) vertical jumps performed with and without a countermovement, 3) maximal cycle test, 4) isokinetic leg extension test, and 5) a maximal isometric test. The experimental group which trained with the load that maximized mechanical power achieved the best overall results in enhancing dynamic athletic performance recording statistically significant (P < 0.05) improvements on most test items and producing statistically superior results to the two other training modalities on the jumping and isokinetic tests.
Article
The purpose of this study was to compare standard (S-weight plus rowing ergometer training) and standard plus plyometric (S+P-weight plus rowing ergometer training, plus plyometric exercises) programs on sport-specific and non sport-specific tests. Twenty-four female rowers completed the weight training or the weight training plus plyometric exercises three times per week and rowing ergometer training four times per week, 1 hr per session for 9 wks. Analysis of variance tests were used to compare S (n = 11; 5 novice and 6 experienced rowers) and S+P (n = 13; 7 novice and 6 experienced rowers) programs on the following sport-specific tests: 1) time to row 2,500 m and 2) distance rowed in 90 s; and on the following non sport-specific tests: 1) leg press, 1 RM, 2) leg press endurance, 3) bench pull 1 RM, 4) bench pull endurance, 5) vertical jump, 6-9) isokinetic knee extensor peak and average power during concentric and eccentric muscle actions and 10) angle of occurrence of peak torque during concentric muscle actions (isokinetic knee extension). Although experienced oarswomen scored significantly higher than did novice oarswomen on eight of 12 tests (p < 0.04), both levels of rower responded similarly to training. No significant differences were observed post-training between the S and S+P training programs (p > 0.05). These results do not discount the value of plyometric exercises, but indicate that the jump exercises used offered no advantages to intercollegiate oarswomen.
Article
Based upon the optimal control solutions to a maximum-height countermovement jump (CMJ) and a maximum-height squat jump (SJ), this paper provides a quantitative description of how tendons and the elastic elements of muscle store and deliver energy during vertical jumping. After confirming the ability of the model to replicate the major features of each jump (i.e. muscle activation patterns, body-segmental motions, ground reaction forces, jump height, and total ground contact time), the time histories of the forces and shortening velocities of all the musculotendon actuators in the model were used to calculate the work done on the skeleton by tendons as well as the series-elastic elements, the parallel-elastic elements, and the contractile elements of muscle. We found that all the elastic tissues delivered nearly the same amount of energy to the skeleton during a CMJ and an SJ. The reason is twofold: first, nearly as much elastic strain energy was stored during the SJ as the CMJ; second, more stored elastic strain energy was lost as heat during the CMJ. There was also a difference in the way energy was stored during each jump. During the CMJ, strain energy stored in the elastic tissues came primarily from the gravitational potential energy of the skeleton as the more proximal extensor muscles were stretched during the downward phase of the jump. During the SJ, on the other hand, energy stored in the elastic tissues came primarily from the contractile elements as they did work to stretch the tendons and the series-elastic elements of the muscles. Increasing tendon compliance in the model led to an increase in elastic energy storage and utilization, but it also decreased the amount of energy delivered by the contractile elements to the skeleton. Jump height therefore remained almost the same for both jumps. These results suggest that elastic energy storage and utilization enhance jumping efficiency much more than overall jumping performance.
Article
Running technique and economy (VO2submax) were examined before and after a 6-wk period of running training. Fifteen males were filmed and performed 10-min economy runs at 3.36 m.s-1 on a treadmill. An incremental treadmill test was used to record running performance and maximal oxygen consumption (VO2max). Subjects were randomly assigned to a training group and a control group that did not participate in any running program. There were no significant changes in kinematic variables between pre- and post-training tests for either group. Neither were there any significant physiological changes over the 6 wk in the control group. However, the training group demonstrated a significantly (P < 0.01) increased VO2max (57.7 +/- 6.2 vs 61.3 +/- 6.3 ml.kg-1.min-1) and running performance. VO2submax in the training group was significantly (P < 0.05) worse (41.0 +/- 4.5 vs 42.4 +/- 4.3 ml.kg-1.min-1) post-training, although the percent utilization of VO2max (71.6 +/- 7.9 vs 69.3 +/- 6.9%) and submaximal heart rate (169 +/- 15 vs 161 +/- 15 beats.min-1) were significantly lower (P < 0.05). The training-induced improvements in running performance could be attributed to physiological rather than biomechanical modifications. There were no changes in biomechanical descriptors of running style that signaled changes in running economy.
Article
The objective of this work was to study the effects of plyometric training on the mechanical properties of the ankle joint in humans. Changes in the mechanical parameters of this musculo-articular structure were quantified with the aid of a sinusoidal perturbation technique. This technique allowed the expression of the mechanical impedance of the musculo-articular system in terms of stiffness, viscosity and inertia. Measurements were performed under passive conditions and when the subject performed plantar flexion. A 7-week period of training induced a decrease in the slope of the relationship between stiffness and plantar flexion torque, whereas passive stiffness was increased. A slight decrease in viscosity and an invariability in inertia were also found. These results are interpreted in terms of the possible adaptations of the musculo-articular structure and ultrastructure involved in the performance of plantar flexion.
Article
Stretch-shortening cycle (SSC) in human skeletal muscle gives unique possibilities to study normal and fatigued muscle function. The in vivo force measurement systems, buckle transducer technique and optic fiber technique, have revealed that, as compared to a pure concentric action, a non-fatiguing SSC exercise demonstrates considerable performance enhancement with increased force at a given shortening velocity. Characteristic to this phenomenon is very low EMG-activity in the concentric phase of the cycle, but a very pronounced contribution of the short-latency stretch-reflex component. This reflex contributes significantly to force generation during the transition (stretch-shortening) phase in SSC action such as hopping and running. The amplitude of the stretch reflex component - and the subsequent force enhancement - may vary according to the increased stretch-load but also to the level of fatigue. While moderate SSC fatigue may result in slight potentiation, the exhaustive SSC fatigue can dramatically reduce the same reflex contribution. SSC fatigue is a useful model to study the processes of reversible muscle damage and how they interact with muscle mechanics, joint and muscle stiffness. All these parameters and their reduction during SSC fatigue changes stiffness regulation through direct influences on muscle spindle (disfacilitation), and by activating III and IV afferent nerve endings (proprioseptic inhibition). The resulting reduced stretch reflex sensitivity and muscle stiffness deteriorate the force potentiation mechanisms. Recovery of these processes is long lasting and follows the bimodal trend of recovery. Direct mechanical disturbances in the sarcomere structural proteins, such as titin, may also occur as a result of an exhaustive SSC exercise bout.
Strength training in female distance runners: impact on running economy Mechanical efficiency of concentric and eccentric exercises performed with medium to fast contraction rates
  • R E Johnston
  • T J Quinn
  • N B Kaneko
  • P V Komi
JOHNSTON, R.E., T.J. QUINN, R. KERTZER, AND N.B. VROMAN. Strength training in female distance runners: impact on running economy. J. Strength Cond. Res. 11:224–229. 1997. 18. KANEKO, M., P.V. KOMI, AND O. AURA. Mechanical efficiency of concentric and eccentric exercises performed with medium to fast contraction rates. Scand. J. Sports Sci. 6:15–20. 1984.
The optimal training load for the development of dynamic athletic performance Acknowledgments This research was supported by Organized Research Funds of The University of Texas at Tyler (FRC Grant 979809
  • R U Newton
  • A J Murphy
WILSON, G.J., R.U. NEWTON, A.J. MURPHY, AND B.J. HUMPHRIES. The optimal training load for the development of dynamic athletic performance. Med. Sci. Sports Exerc. 25:1279–1286. 1993. Acknowledgments This research was supported by Organized Research Funds of The University of Texas at Tyler (FRC Grant 979809). Address correspondence to Dr. James A. Schwane, jschwane@mail.uttyl.edu.