Papadopoulos Christos, Theodosiou Konstantinos, Bogdanis Gregory C, Gkantiraga Evangelia, Gissis Ioannis, Sambanis Michalis, Souglis Athanasios, Sotiropoulos Aristomenis
1Laboratory of Sport Biomechanics, Faculty of Physical Education and Sports Science, Aristotle University of Thessaloniki, Serres, Greece; and 2Faculty of Physical Education and Sports Science, University of Athens, Athens, Greece.
J Strength Cond Res. 2014 Sep;28(9):2680-8. doi: 10.1519/JSC.0000000000000456.
This study investigated the effects of short-term eccentric exercise training using a custom-made isokinetic leg press device, on concentric and eccentric strength and explosiveness as well as jumping performance. Nineteen healthy males were divided into an eccentric (ECC, n = 10) and a control group (CG, n = 9). The ECC group trained twice per week for 8 weeks using an isokinetic hydraulic leg press machine against progressively increasing resistance ranging from 70 to 90% of maximal eccentric force. Jumping performance and maximal force generating capacity were measured before and after eccentric training. In the ECC group, drop jump (DJ) height and maximal power were increased by 13.6 ± 3.2% (p < 0.01) and 25.8 ± 1.2% (p < 0.01), whereas ground contact time was decreased by 17.6 ± 2.6% (p < 0.01). Changes in ankle, knee, and hip joint angles were also reduced by 33.9 ± 1.1%, 31.1 ± 1.0%, and 32.4 ± 1.6% (all p < 0.01), respectively, indicating an increase in muscle stiffness during the DJ. Maximal eccentric and concentric leg press force was increased by 64.9 ± 5.5% (p < 0.01) and 32.2 ± 8.8% (p < 0.01), respectively, and explosiveness, measured as force attained in the first 300 milliseconds, was increased by 49.1 ± 4.8% (p < 0.01) and 77.1 ± 7.7% (p < 0.01), respectively. The CG did not show any statistically significant changes in all parameters measured. The main findings of this study were that maximal concentric and eccentric force, explosiveness, and DJ performance were markedly increased after only 16 training sessions, possibly because of the high eccentric load attained during the bilateral eccentric leg press exercise performed on this custom-made device.
本研究使用定制的等动腿部推举装置，调查了短期离心运动训练对向心力量、离心力量、爆发力以及跳跃性能的影响。19名健康男性被分为离心训练组（ECC，n = 10）和对照组（CG，n = 9）。ECC组每周使用等动液压腿部推举机训练两次，共8周，对抗逐渐增加的阻力，阻力范围为最大离心力的70%至90%。在离心训练前后测量跳跃性能和最大力量产生能力。在ECC组中，垂直跳（DJ）高度和最大功率分别增加了13.6 ± 3.2%（p < 0.01）和25.8 ± 1.2%（p < 0.01），而触地时间减少了17.6 ± 2.6%（p < 0.01）。踝关节、膝关节和髋关节角度的变化也分别减少了33.9 ± 1.1%、31.1 ± 1.0%和32.4 ± 1.6%（均p < 0.01），表明在DJ过程中肌肉僵硬度增加。最大离心和向心腿部推举力量分别增加了64.9 ± 5.5%（p < 0.01）和32.2 ± 8.8%（p < 0.01），以最初300毫秒内达到的力量衡量的爆发力分别增加了49.1 ± 4.8%（p < 0.01）和77.1 ± 7.7%（p < 0.01）。CG组在所有测量参数上均未显示出任何统计学上的显著变化。本研究的主要发现是，仅经过16次训练后，最大向心和离心力量、爆发力以及DJ性能就显著提高，这可能是因为在这种定制装置上进行双侧离心腿部推举运动时达到了较高的离心负荷。
