Struzik Artur, Juras Grzegorz, Pietraszewski Bogdan, Rokita Andrzej
Department of Team Sport Games, University School of Physical Education, Wroclaw, Poland.
Department of Motor Behavior, Academy of Physical Education, Katowice, Poland.
J Hum Kinet. 2016 Sep 10;52:157-164. doi: 10.1515/hukin-2016-0003. eCollection 2016 Sep 1.
The basic drill of plyometric training aimed at improving lower limb power and jump height is a drop jump. This exercise can be performed using different techniques, which substantially affects jump variables. Therefore, the aim of this study was to compare the values of the reactive strength index (RSI) for countermovement drop jumps (CDJs) and bounce drop jumps (BDJs). The study was carried out in a group of 8 male youth basketball players. The tests were conducted using the AMTI BP600900 force plate to measure ground reaction forces and the Noraxon MyoMotion system to record kinematic data. Each player performed two CDJs and two BDJs from the height of 15, 30, 45 and 60 cm. The RSI was calculated as a ratio of jump height and contact time. Moreover, the RSI was determined for the amortization and take-off phases separately. Significant differences (p < 0.05) between RSI values for CDJs and BDJs were recorded for jumps from 30, 45 and 60 cm. Differences in RSI values for jumps from 15 cm were not significant. Furthermore, CDJ height values were significantly higher (p < 0.05) than the values recorded for BDJs. Times of contact, amortization and take-off during BDJs were significantly shorter (p < 0.05) than the respective values obtained for CDJs. Therefore, the use of the RSI to monitor plyometric training should be based on the drop jump technique that is commonly performed by basketball players.
旨在提高下肢力量和跳跃高度的增强式训练的基本练习是跳深。这项练习可以使用不同的技术来进行，这会对跳跃变量产生重大影响。因此，本研究的目的是比较反向跳深（CDJ）和反弹跳深（BDJ）的反应力量指数（RSI）值。该研究在一组8名男性青年篮球运动员中进行。测试使用AMTI BP600900测力台测量地面反作用力，并使用Noraxon MyoMotion系统记录运动学数据。每位运动员从15厘米、30厘米、45厘米和60厘米的高度进行两次CDJ和两次BDJ。RSI计算为跳跃高度与接触时间的比值。此外，还分别确定了缓冲阶段和起跳阶段的RSI。从30厘米、45厘米和60厘米的高度进行跳跃时，记录到CDJ和BDJ的RSI值存在显著差异（p < 0.05）。从15厘米的高度进行跳跃时，RSI值的差异不显著。此外，CDJ的高度值显著高于BDJ记录的值（p < 0.05）。BDJ期间的接触时间、缓冲时间和起跳时间显著短于CDJ获得的相应值（p < 0.05）。因此，使用RSI监测增强式训练应基于篮球运动员通常进行的跳深技术。
