Gupta Dhruv, Donnelly Cyril J, Jensen Jody L, Reinbolt Jeffrey A
Mechanical, Aerospace and Biomedical Engineering, The University of Tennessee, Knoxville, TN 37996, USA.
Rehabilitation Research Institute of Singapore, Nanyang Technological University, Singapore 308232, Singapore.
Life (Basel). 2021 Jun 22;11(7):598. doi: 10.3390/life11070598.
Performance enhancement and injury prevention are often perceived as opposite sides of a coin, where focusing on improvements of one leads to detriment of the other. In this study, we used physics-based simulations with novel optimization methods to find participant-specific, whole-body mechanics of volleyball spiking that enhances performance (the peak height of the hitting hand and its forward velocity) while minimizing injury risk. For the volleyball spiking motion, the shoulder is the most common injury site because of the high mechanical loads that are most pronounced during the follow-through phase of the movement. We analyzed 104 and 209 spiking trials across 13 participants for the power and follow-through phases, respectively. During the power phase, simulations increased ( < 0.025) the peak height of the hitting wrist by 1% and increased ( < 0.025) the forward wrist velocity by 25%, without increasing peak shoulder joint torques, by increasing the lower-limb forward swing (i.e., hip flexion, knee extension). During the follow-through phase, simulations decreased ( < 0.025) peak shoulder joint torques by 75% elicited by synergistic rotation of the trunk along the pathway of the hitting arm. Our results show that performance enhancement and injury prevention are not mutually exclusive and may both be improved simultaneously, potentially leading to better-performing and injury-free athletes.
提高运动表现和预防损伤常常被视为一枚硬币的两面，专注于其中一方面的提升往往会对另一方面造成损害。在本研究中，我们使用基于物理的模拟和新颖的优化方法，来找出针对个体的、能提高排球扣球表现（击球手的峰值高度及其向前速度）同时将受伤风险降至最低的全身力学机制。对于排球扣球动作，肩部是最常见的受伤部位，因为在动作的随挥阶段机械负荷最大。我们分别分析了13名参与者在发力阶段和随挥阶段的104次和209次扣球试验。在发力阶段，模拟通过增加下肢向前摆动（即髋部屈曲、膝部伸展），在不增加肩关节峰值扭矩的情况下，使击球手腕的峰值高度提高了1%（<0.025），并使手腕向前速度提高了25%（<0.025）。在随挥阶段，模拟通过沿击球手臂路径的躯干协同旋转所引发的肩关节峰值扭矩降低了75%（<0.025）。我们的结果表明，提高运动表现和预防损伤并非相互排斥，二者可能同时得到改善，这有可能造就表现更佳且无伤病的运动员。
