Adaptation mechanisms of the knee extensors contractile properties in response to short-term stretch-shortening exercise training

作者：Negyesi Janos^*; Vaczi Mark; Magyar Oliver Matyas; Pantovic Milan; Tihanyi Jozsef; Racz Levente

来源：Isokinetics and Exercise Science, 2017, 25(1): 65-72.

DOI：10.3233/IES-160646

• Plyometric exercises
• dynamometer
• stretch-load

BACKGROUND: The effects of stretch-shortening cycle (SSC) training are well-described in the literature but the mechanism of how it changes the characteristics of the SSC moment-time curve and contraction velocity is unknown.
OBJECTIVE: The purpose of the present study was to investigate the adaptation mechanisms of the knee extensor contractile properties in response to a short-term unilateral SSC exercise training.
METHODS: Twenty-four subjects (22.9 +/- 2.4 years) were randomised to an experimental or control group. A custom-built dynamometer was used to test the mechanical properties of the quadriceps muscle. Each subject participated in the pre-, and post-test session. Subjects in the experimental group participated in nine training sessions and performed maximal voluntary stretch-shortening cycle contractions on the dynamometer. Changes in the knee extensor contractile properties were measured from an SSC curve.
RESULTS: Multivariate analysis of variance (MANOVA) revealed a significant multivariate effect for the measured variables in relation to group assignment. SSC exercise training significantly changed concentric moment (M-CC, F-1,F-22 = 96.2, p = 0.000), and contraction velocity (F-1,F-22 = 125.6, p = 0.000) resulting in a 29.6% improvement in concentric peak angular velocity (omega). Stepwise multiple regression analysis showed that. was significantly predicted only by M-CC (r = 0.751, p = 0.005).
CONCLUSIONS: Short-term unilateral SSC exercise training modifies the characteristics of the SSC moment-time curve and contraction velocity through the mechanical adaptation of the knee extensor contractile properties.

• 出版日期2017