Tufano James J, Malecek Jan, Steffl Michal, Stastny Petr, Hojka Vladimir, Vetrovsky Tomas
Department of Physiology and Biochemistry, Faculty of Physical Education and Sport, Charles University, Prague, Czechia.
Department of Sport Games, Faculty of Physical Education and Sport, Charles University, Prague, Czechia.
Front Physiol. 2018 Sep 12;9:1284. doi: 10.3389/fphys.2018.01284. eCollection 2018.
Assisted jumping can supplement resistance training and traditional plyometric training to increase vertical jump performance. However, as coaches may choose to make field-based decisions based on lab-based research, this study determined whether a field-based assisted jumping set-up results in different ground contact times (CT), take off forces (TOF), flight times (FT), and impact forces (IF) compared to a lab-based set-up. Eighteen active males (24.8 ± 3.0 yr; 178.8 ± 7.8 cm; 77.8 ± 7.8 kg) performed two sessions of assisted jumping: one with each hand holding a commercially available resistance band (1m) that was attached to a pull-up bar (), and the other with assistance from a custom-built system of ropes, pulleys, and long (3 m) elastic bands (). With each set-up, subjects performed five sets of five countermovement jumps on a force plate. Each set was performed with either bodyweight (BW), 90, 80, 70, or 60% of BW, which was achieved by either grabbing higher or lower on the bands during , or by being pulled upward via a full-body harness during . The order of each visit was counter-balanced, and the order of jumps within each visit was quasi-randomized. Data from the 90, 80, 70, and 60% trials for each set-up were then expressed relative to the data of BW jumps, and these relative values were then used for analysis. CT was less than CT at 80, 70, and 60%. FT was greater than FT at 90 and 80%, but FT became greater at 60%. TOF and IF remained unchanged during , but TOF was consistently less than TOF during BW, with IF generally being greater than IF. If the purpose of assisted jumping is to spend less time on the ground without decreasing force, systems with finite adjustments and longer bands like should be used. However, shorter bands similar to may also be used; but due to the larger variability of assistance throughout the range of motion, such systems may alter the neuromuscular characteristics of the jump in other ways that should be investigated in future research.
助力跳跃可以补充阻力训练和传统的增强式训练，以提高垂直跳跃成绩。然而，由于教练可能会根据实验室研究做出基于场地的决策，本研究确定了与基于实验室的设置相比，基于场地的助力跳跃设置是否会导致不同的地面接触时间（CT）、起跳力（TOF）、飞行时间（FT）和冲击力（IF）。18名活跃男性（24.8±3.0岁；178.8±7.8厘米；77.8±7.8千克）进行了两阶段的助力跳跃：一次是双手各持一条连接到引体向上杆的市售阻力带（1米），另一次是在定制的绳索、滑轮和长（3米）弹性带系统的辅助下进行。对于每种设置，受试者在测力板上进行五组，每组五次反向运动跳跃。每组跳跃时，受试者分别采用体重（BW）、体重的90%、80%、70%或60%的负荷，这通过在跳跃过程中在阻力带上抓握更高或更低的位置，或者在跳跃过程中通过全身安全带向上拉动来实现。每次测试的顺序进行了平衡，每次测试中跳跃的顺序为准随机排列。然后将每种设置下90%、80%、70%和60%测试的数据相对于体重跳跃的数据进行表示，并将这些相对值用于分析。在80%、70%和60%负荷时，CT小于体重负荷时的值。在90%和80%负荷时，FT大于体重负荷时的值，但在60%负荷时FT变得更大。在跳跃过程中，TOF和IF保持不变，但在体重负荷时，TOF始终小于体重负荷时的值，IF通常大于体重负荷时的值。如果助力跳跃的目的是在不降低力量的情况下减少地面接触时间，则应使用具有有限调节功能和较长带子（如）的系统。然而，也可以使用类似于的较短带子；但由于在整个运动范围内辅助的变异性较大，此类系统可能会以其他方式改变跳跃的神经肌肉特征，这应在未来的研究中进行调查。
