Maxwell N S, Aitchison T C, Nimmo M A
Department of Physical Education, Sport and Outdoor Education, University of Strathclyde, Glasgow, UK.
Exp Physiol. 1996 Sep;81(5):833-45. doi: 10.1113/expphysiol.1996.sp003980.
The purpose of this study was to test the hypothesis that intermittent supramaximal running would be negatively affected when performed in a hot humid environment. Twelve physically active, male volunteers took part in this study. The exercise model was performed under three environmental trial conditions, randomly assigned and separated by 1 week. This included performing: (a) a standardized warm-up in the cool environment and a repeated sprint test in the cool environment (CC); (b) a standardized warm-up in the cool environment and a repeated sprint test in a hot, humid environment (CH); and (c) a standardized warm-up in a hot, humid environment and a repeated sprint test in a hot, humid environment (HH). The repeated sprint test involved 20 s runs, each at increasing-intensity, with 100s passive recovery between successive sprints. Capillary blood samples were taken post-warm-up and at 1, 3 and 6 min post-repeated sprint test for the determination of plasma lactate, ammonia and glucose concentrations and the percentage change in plasma volume. Rectal, aural and mean skin temperature were measured continuously throughout each trial condition. Sweat loss was estimated from the change in body mass. Sweat loss was significantly greater in the HH trial than in the CH trial and in the CH trial than in the CC trial (P < 0.0001). Performance was significantly better in the CC trial than in the CH and HH trials (CC vs. CH and HH: 151 +/- 4 vs. 144 +/- 5 and 140 +/- 5 s, respectively, P = 0.02). For the post-exercise data, significant differences were found between the CC and the CH and HH trials in rectal (P = 0.007), aural (P < 0.001) and mean skin temperatures (P < 0.001). No significant differences were found in post-repeated sprint test lactate and ammonia concentrations, or in plasma volume among trial conditions, but glucose concentrations were higher in the CH and HH trials than in the CC trial (P = 0.005). No significant differences were found in performance, body temperature or any blood measurement between the CH and HH trials. Intermittent supramaximal running performance was detrimentally affected by a hot, humid environment, resulting in performance being significantly less in the CH and HH trials than in the CC trial.
在炎热潮湿环境中进行间歇性超最大强度跑步时，跑步表现会受到负面影响。12名身体活跃的男性志愿者参与了本研究。运动模式在三种环境试验条件下进行，试验条件随机分配，且每次试验间隔1周。这三种试验条件包括：(a) 在凉爽环境中进行标准热身，然后在凉爽环境中进行重复冲刺测试（CC）；(b) 在凉爽环境中进行标准热身，然后在炎热潮湿环境中进行重复冲刺测试（CH）；(c) 在炎热潮湿环境中进行标准热身，然后在炎热潮湿环境中进行重复冲刺测试（HH）。重复冲刺测试包括每次持续20秒、强度递增的跑步，连续冲刺之间有100秒的被动恢复时间。在热身结束后以及重复冲刺测试后的第1、3和6分钟采集毛细血管血样，以测定血浆乳酸、氨和葡萄糖浓度以及血浆容量的百分比变化。在每种试验条件下，持续测量直肠温度、耳温及平均皮肤温度。通过体重变化估算出汗量。HH试验中的出汗量显著高于CH试验，CH试验中的出汗量显著高于CC试验（P < 0.0001）。CC试验中的表现显著优于CH试验和HH试验（CC与CH及HH试验相比：分别为151±4秒、144±5秒和140±5秒，P = 0.02）。对于运动后的数据，CC试验与CH试验和HH试验在直肠温度（P = 0.007）、耳温（P < 0.001）和平均皮肤温度方面存在显著差异（P < 0.001）。在重复冲刺测试后的乳酸和氨浓度或各试验条件下的血浆容量方面未发现显著差异，但CH试验和HH试验中的葡萄糖浓度高于CC试验（P = 0.005）。CH试验和HH试验在表现、体温或任何血液检测指标方面未发现显著差异。间歇性超最大强度跑步表现受到炎热潮湿环境的不利影响，导致CH试验和HH试验中的表现显著低于CC试验。
