Murata Munenori, Naito Takashi
Department of Faculty of Sports and Life Science, National Institute of Fitness and Sports in Kanoya, Kanoya, Japan.
Faculty of Law, Hokkai-Gakuen University, Sapporo, Japan.
Front Sports Act Living. 2023 Feb 13;5:1113717. doi: 10.3389/fspor.2023.1113717. eCollection 2023.
Assessment of fatigue effect on hitting ability in tennis has been controversial in previous studies. The purpose of this study was to determine the relationship between player fatigue and groundstroke type in tennis. We hypothesized that subjects with higher blood lactate concentration during play would apply heavier spin to the ball. We divided players into two groups based on their blood lactate concentration during a pre-measured hitting test (HIGH and LOW). Each group performed a simulated match-play protocol consisting of repeated running and hitting tests, which simulated a three-set match. Heart rate, percent of heart rate reserve, oxygen uptake, pulmonary ventilation, and respiratory exchange were measured. The distance between the ball's landing point and the target, and the ball's kinematics, were recorded during the hitting test between sets. We found no significant difference in ball kinetic energy between groups, but the HIGH group hit the ball with a greater ratio of rotational kinetic energy to total kinetic energy. However, the progression of the simulation protocol did not affect physiological responses (including blood lactate concentration) or hitting ability. Therefore, it is suggested that the type of groundstrokes used by players is one of the factors that should be considered when discussing fatigue in tennis.
在以往的研究中，评估疲劳对网球击球能力的影响一直存在争议。本研究的目的是确定网球运动员疲劳与击球类型之间的关系。我们假设，比赛期间血乳酸浓度较高的受试者会给球施加更大的旋转。在预先测量的击球测试中，我们根据运动员的血乳酸浓度将他们分为两组（高浓度组和低浓度组）。每组都执行了一个模拟比赛方案，该方案包括重复的跑步和击球测试，模拟了一场三盘比赛。测量了心率、心率储备百分比、摄氧量、肺通气量和呼吸交换率。在各盘之间的击球测试中，记录了球的落点与目标之间的距离以及球的运动学数据。我们发现两组之间的球动能没有显著差异，但高浓度组击球时旋转动能与总动能的比值更大。然而，模拟方案的进程并未影响生理反应（包括血乳酸浓度）或击球能力。因此，建议在讨论网球运动中的疲劳时，运动员使用的击球类型是应考虑的因素之一。
