Zubac Damir, Paravlić Armin, Koren Katja, Felicita Urzi, Šimunič Boštjan
University of Split, Faculty of Kinesiology, Croatia.
J Musculoskelet Neuronal Interact. 2019 Mar 1;19(1):38-49.
This study investigated the effects of an 8-week plyometric training (PT) session on countermovement jump (CMJ) height, take-off velocity, and Tensiomyography (TMG) derived contractile parameters in seniors.
Twenty-three senior adults (age 66.7±5.2 years) were randomly divided into two groups: PLYO (n=11) and CTRL (n=12). Tensiomyography was measured in vastus lateralis (VL), biceps femoris (BF), tibialis anterior (TA), gastrocnemius medialis (GM), and lateralis (GL). Additionally, the electromechanical efficiency (EME) index was calculated in GM as a ratio between amplitudes of peak-to-peak M-wave and TMG (Dm) responses. Biochemical markers of muscle damage and inflammation were evaluated to provide indirect indices of exercise protocol safety.
The main effect of time (for take-off velocity p=.023; ɳ= .236) and group x time interactions (for CMJ, Tc (BF, GM), Dm (BF) and EME p<.05; ɳ= .136 - .236) were observed. Post hoc analysis showed a significant increase in CMJ height and take-off velocity, namely by 14.2% (p=.001) and 8.2% (p=.01) in PLYO, respectively. Contraction time (Tc) decreased in BF -5.7% (p=.001) and GM -9.6% (p=.001). Dm decreased only in BF -20.8% (p=.001), while the EME index of the GM improved by 22.9% (p=.002). There were no differences between groups or assessment time points for C-reactive protein (p=.122).
The present study clearly supports the application of supervised PT exercise in seniors, since explosive power, muscle contractility, and EME of the lower limbs were markedly improved after training.
本研究调查了为期8周的增强式训练（PT）课程对老年人反向运动跳（CMJ）高度、起跳速度以及张力肌电图（TMG）得出的收缩参数的影响。
23名老年人（年龄66.7±5.2岁）被随机分为两组：增强式训练组（PLYO，n = 11）和对照组（CTRL，n = 12）。在股外侧肌（VL）、股二头肌（BF）、胫骨前肌（TA）、腓肠肌内侧头（GM）和外侧头（GL）测量张力肌电图。此外，计算腓肠肌内侧头的机电效率（EME）指数，即峰峰值M波与TMG（Dm）反应幅度的比值。评估肌肉损伤和炎症的生化标志物，以提供运动方案安全性的间接指标。
观察到时间的主效应（起跳速度p = 0.023；ŋ = 0.236）以及组×时间交互作用（CMJ、收缩时间（BF、GM）、Dm（BF）和EME，p < 0.05；ŋ = 0.136 - 0.236）。事后分析显示，增强式训练组的CMJ高度和起跳速度显著增加，分别增加了14.2%（p = 0.001）和8.2%（p = 0.01）。股二头肌的收缩时间（Tc）下降了5.7%（p = 0.001），腓肠肌内侧头下降了9.6%（p = 0.001）。仅股二头肌的Dm下降了20.8%（p = 0.001），而腓肠肌内侧头的EME指数提高了22.9%（p = 0.002）。两组之间或各评估时间点的C反应蛋白无差异（p = 0.122）。
本研究明确支持在老年人中应用有监督的PT运动，因为训练后下肢的爆发力、肌肉收缩力和EME均有显著改善。
