1. Effects of Peroneal Muscles Fatigue on Dynamic Stability Following Lateral Hop Landing: Time to Stabilization Versus Dynamic Postural Stability Index.
- Author
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Malmir, Kazem, Olyaei, Gholam Reza, Talebian, Saeed, Jamshidi, Ali Ashraf, and Ganguie, Majid Ashraf
- Subjects
LEG physiology ,MUSCLE physiology ,POSTURAL balance ,EXERCISE tests ,FOOT ,HEMODYNAMICS ,RESEARCH methodology ,MUSCLE contraction ,STATISTICAL sampling ,T-test (Statistics) ,TIME ,TORQUE ,BODY movement ,PRE-tests & post-tests ,DATA analysis software ,DESCRIPTIVE statistics ,MUSCLE fatigue - Abstract
Context: Dynamic stability is a necessary requirement in many sports competitions. Muscle fatigue, which can impair stability, may be occurred in many sports competitions in which lateral movements and landing repeated frequently. Objective: To assess the effects of peroneal muscles fatigue on dynamic stability following lateral hop landing through measuring time to stabilization (TTS) and dynamic postural stability index (DPSI). Design: Quasi-experimental. Setting: Laboratory study. Participants: A total of 20 recreationally active, healthy males with no lower-extremity injury during the previous 6 months participated in this study. Intervention: Participants performed a lateral hop on a force plate before and immediately after a fatigue intervention using a Biodex dynamometer. For inducing fatigue, the participant made a prolonged eversion effort with 40% of the maximal voluntary contraction. Fatigue was met when the eversion torque declined by 50% of the initial value. TTS and DPSI were calculated using sequential averaging method and relevant formulas, respectively. Main Outcome Measures: Premeasures and postmeasures of TTS in the anteroposterior, mediolateral and vertical directions, resultant vector of TTS, stability indices in the anteroposterior, mediolateral and vertical directions, and DPSI. Results: Means of the DPSI or its components did not change significantly due to fatigue (P >.05). Means of the TTS in the anteroposterior and mediolateral directions, and the mean of the resultant vector of the TTS increased significantly after fatigue (P <.05). Conclusions: The question that the dynamic stability is affected or not affected by fatigue depends on which of the TTS or DPSI is used for analysis. The TTS may be a sensitive measure to detect subtle changes in postural stability due to fatigue. But, the DPSI which may be changed after a more strenuous fatigue may be related to actual fatiguing situations. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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