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Static stretching alters neuromuscular function and pacing strategy, but not performance during a 3-km running time-trial.

Damasceno MV, Duarte M, Pasqua LA, Lima-Silva AE, MacIntosh BR, Bertuzzi R - PLoS ONE (2014)

Bottom Line: The overall running time did not change with condition (SS 11:35±00:31 s; control 11:28±00:41 s, p = 0.304), but the first 100 m was completed at a significantly lower velocity after SS.Surprisingly, SS did not modify the running economy, but the iEMG for the BF (+22.6%, p = 0.031), stride duration (+2.1%, p = 0.053) and range of motion (+11.1%, p = 0.0001) were significantly modified.Drop jump height decreased following SS (-9.2%, p = 0.001).

View Article: PubMed Central - PubMed

Affiliation: Endurance Performance Research Group, School of Physical Education and Sport, University of São Paulo, São Paulo, São Paulo, Brazil.

ABSTRACT

Purpose: Previous studies report that static stretching (SS) impairs running economy. Assuming that pacing strategy relies on rate of energy use, this study aimed to determine whether SS would modify pacing strategy and performance in a 3-km running time-trial.

Methods: Eleven recreational distance runners performed a) a constant-speed running test without previous SS and a maximal incremental treadmill test; b) an anthropometric assessment and a constant-speed running test with previous SS; c) a 3-km time-trial familiarization on an outdoor 400-m track; d and e) two 3-km time-trials, one with SS (experimental situation) and another without (control situation) previous static stretching. The order of the sessions d and e were randomized in a counterbalanced fashion. Sit-and-reach and drop jump tests were performed before the 3-km running time-trial in the control situation and before and after stretching exercises in the SS. Running economy, stride parameters, and electromyographic activity (EMG) of vastus medialis (VM), biceps femoris (BF) and gastrocnemius medialis (GA) were measured during the constant-speed tests.

Results: The overall running time did not change with condition (SS 11:35±00:31 s; control 11:28±00:41 s, p = 0.304), but the first 100 m was completed at a significantly lower velocity after SS. Surprisingly, SS did not modify the running economy, but the iEMG for the BF (+22.6%, p = 0.031), stride duration (+2.1%, p = 0.053) and range of motion (+11.1%, p = 0.0001) were significantly modified. Drop jump height decreased following SS (-9.2%, p = 0.001).

Conclusion: Static stretch impaired neuromuscular function, resulting in a slow start during a 3-km running time-trial, thus demonstrating the fundamental role of the neuromuscular system in the self-selected speed during the initial phase of the race.

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Related in: MedlinePlus

Variables measured with and without previous static stretching treatment.A and B panels show the running speed and rating of perceived exertion during a 3-km running time-trial, respectively. C and D panels show the drop jump and sit-and-reach tests performed prior to and immediately after static stretching treatment. * Significantly different from control situation (p≤0.05). #Significant difference over time in each condition (p≤0.05).
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pone-0099238-g002: Variables measured with and without previous static stretching treatment.A and B panels show the running speed and rating of perceived exertion during a 3-km running time-trial, respectively. C and D panels show the drop jump and sit-and-reach tests performed prior to and immediately after static stretching treatment. * Significantly different from control situation (p≤0.05). #Significant difference over time in each condition (p≤0.05).

Mentions: Variables measured during time-trial tests performed with and without previous static stretching are presented in figure 2. The speed-distance curve during 3-km running showed a classical U-shape in both conditions. It was detected that the first section (100 m) was completed at a significantly slower speed in the SS condition (very likely harmful, −1.1±1.0 km.h−1 95% CL), compared with the control condition (p = 0.036). However, the overall running time to cover 3-km running during the control condition (11:28±00:41min:s) was not significantly different from that during the SS condition (11:35±00:31min:s) (trivial, 7.0±13.9 s 95% CL). The RPE increased significantly over time in both conditions (p = 0.001). The RPE in the SS condition was statistically greater than that in the control condition only during the first 800 m (p = 0.019). Following SS, the athletes also demonstrated reduced drop jump height (p = 0.001) and improved performance on the sit-and-reach test (p = 0.0001) relative to measures obtained prior to SS protocol. There were no differences in drop jump height (p = 0.351) and sit-and-reach test (p = 0.262) before the 3-km running when the control and experimental situations were compared.


Static stretching alters neuromuscular function and pacing strategy, but not performance during a 3-km running time-trial.

Damasceno MV, Duarte M, Pasqua LA, Lima-Silva AE, MacIntosh BR, Bertuzzi R - PLoS ONE (2014)

Variables measured with and without previous static stretching treatment.A and B panels show the running speed and rating of perceived exertion during a 3-km running time-trial, respectively. C and D panels show the drop jump and sit-and-reach tests performed prior to and immediately after static stretching treatment. * Significantly different from control situation (p≤0.05). #Significant difference over time in each condition (p≤0.05).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4048241&req=5

pone-0099238-g002: Variables measured with and without previous static stretching treatment.A and B panels show the running speed and rating of perceived exertion during a 3-km running time-trial, respectively. C and D panels show the drop jump and sit-and-reach tests performed prior to and immediately after static stretching treatment. * Significantly different from control situation (p≤0.05). #Significant difference over time in each condition (p≤0.05).
Mentions: Variables measured during time-trial tests performed with and without previous static stretching are presented in figure 2. The speed-distance curve during 3-km running showed a classical U-shape in both conditions. It was detected that the first section (100 m) was completed at a significantly slower speed in the SS condition (very likely harmful, −1.1±1.0 km.h−1 95% CL), compared with the control condition (p = 0.036). However, the overall running time to cover 3-km running during the control condition (11:28±00:41min:s) was not significantly different from that during the SS condition (11:35±00:31min:s) (trivial, 7.0±13.9 s 95% CL). The RPE increased significantly over time in both conditions (p = 0.001). The RPE in the SS condition was statistically greater than that in the control condition only during the first 800 m (p = 0.019). Following SS, the athletes also demonstrated reduced drop jump height (p = 0.001) and improved performance on the sit-and-reach test (p = 0.0001) relative to measures obtained prior to SS protocol. There were no differences in drop jump height (p = 0.351) and sit-and-reach test (p = 0.262) before the 3-km running when the control and experimental situations were compared.

Bottom Line: The overall running time did not change with condition (SS 11:35±00:31 s; control 11:28±00:41 s, p = 0.304), but the first 100 m was completed at a significantly lower velocity after SS.Surprisingly, SS did not modify the running economy, but the iEMG for the BF (+22.6%, p = 0.031), stride duration (+2.1%, p = 0.053) and range of motion (+11.1%, p = 0.0001) were significantly modified.Drop jump height decreased following SS (-9.2%, p = 0.001).

View Article: PubMed Central - PubMed

Affiliation: Endurance Performance Research Group, School of Physical Education and Sport, University of São Paulo, São Paulo, São Paulo, Brazil.

ABSTRACT

Purpose: Previous studies report that static stretching (SS) impairs running economy. Assuming that pacing strategy relies on rate of energy use, this study aimed to determine whether SS would modify pacing strategy and performance in a 3-km running time-trial.

Methods: Eleven recreational distance runners performed a) a constant-speed running test without previous SS and a maximal incremental treadmill test; b) an anthropometric assessment and a constant-speed running test with previous SS; c) a 3-km time-trial familiarization on an outdoor 400-m track; d and e) two 3-km time-trials, one with SS (experimental situation) and another without (control situation) previous static stretching. The order of the sessions d and e were randomized in a counterbalanced fashion. Sit-and-reach and drop jump tests were performed before the 3-km running time-trial in the control situation and before and after stretching exercises in the SS. Running economy, stride parameters, and electromyographic activity (EMG) of vastus medialis (VM), biceps femoris (BF) and gastrocnemius medialis (GA) were measured during the constant-speed tests.

Results: The overall running time did not change with condition (SS 11:35±00:31 s; control 11:28±00:41 s, p = 0.304), but the first 100 m was completed at a significantly lower velocity after SS. Surprisingly, SS did not modify the running economy, but the iEMG for the BF (+22.6%, p = 0.031), stride duration (+2.1%, p = 0.053) and range of motion (+11.1%, p = 0.0001) were significantly modified. Drop jump height decreased following SS (-9.2%, p = 0.001).

Conclusion: Static stretch impaired neuromuscular function, resulting in a slow start during a 3-km running time-trial, thus demonstrating the fundamental role of the neuromuscular system in the self-selected speed during the initial phase of the race.

Show MeSH
Related in: MedlinePlus