Int J Sports Physiol Perform. 2020 Jun 26;15(10):1393-1399. doi: 10.1123/ijspp.2019-0837.
Exercise in hot environments increases body temperature and thermoregulatory strain. However, little is known regarding the magnitude of effect that ambient temperature (Ta), relative humidity (RH), and solar radiation individually have on team-sport athletes.
To determine the effect of these individual heat-stress variables on team-sport training performance and recovery.
Professional Australian Rules Football players (N = 45) undertook 8-wk preseason training producing a total of 579 outdoor field-based observations with Ta, RH, and solar radiation recorded at every training session. External load (distance covered, in m/min; percentage high-speed running [%HSR] >14.4 km/h) was collected via a global positioning system. Internal load (ratings of perceived exertion and heart rate) and recovery (subjective ratings of well-being and heart-rate variability [root mean square of the successive differences]) were monitored throughout the training period. Mixed-effects linear models analyzed relationships between variables using standardized regression coefficients.
Increased solar-radiation exposure was associated with reduced distance covered (-19.7 m/min, P < .001), %HSR (-10%, P < .001) during training and rMSSD 48 h posttraining (-16.9 ms, P = .019). Greater RH was associated with decreased %HSR (-3.4%, P = .010) but increased percentage duration >85% HRmax (3.9%, P < .001), ratings of perceived exertion (1.8 AU, P < .001), and self-reported stress 24 h posttraining (-0.11 AU, P = .002). In contrast, higher Ta was associated with increased distance covered (19.7 m/min, P < .001) and %HSR (3.5%, P = .005).
The authors show the importance of considering the individual factors contributing to thermal load in isolation for team-sport athletes and that solar radiation and RH reduce work capacity during team-sport training and have the potential to slow recovery between sessions.
在炎热环境中运动可导致体温升高和热应激增加。然而，关于环境温度（Ta）、相对湿度（RH）和太阳辐射单独对团队运动运动员的影响程度，人们知之甚少。
确定这些单个热应激变量对团队运动训练表现和恢复的影响。
45 名澳大利亚澳式足球职业运动员完成 8 周的赛前训练，共进行了 579 次室外实地观测，每次训练均记录 Ta、RH 和太阳辐射。通过全球定位系统收集外部负荷（以 m/min 计的距离；>14.4km/h 的高速跑百分比 [%HSR]）。在整个训练期间监测内部负荷（感知用力程度和心率）和恢复情况（主观幸福感评分和心率变异性[均方根差的连续差异]）。使用标准化回归系数，混合效应线性模型分析变量之间的关系。
暴露于更多的太阳辐射与训练中距离减少（-19.7m/min，P<.001）、%HSR 减少（-10%，P<.001）和训练后 48 小时 rMSSD 减少（-16.9ms，P=.019）相关。较高的 RH 与 %HSR 减少（-3.4%，P=.010）相关，但与超过 85%HRmax 的时间百分比增加（3.9%，P<.001）、感知用力程度（1.8AU，P<.001）和训练后 24 小时的自我报告压力（-0.11AU，P=.002）增加相关。相比之下，较高的 Ta 与距离增加（19.7m/min，P<.001）和%HSR 增加（3.5%，P=.005）相关。
作者表明，考虑到单独的热负荷因素对团队运动运动员的重要性，并且太阳辐射和 RH 降低了团队运动训练中的工作能力，并有可能减缓训练之间的恢复。
