Department of Sport, Health and Nutrition, Leeds Trinity University, Brownberrie Lane, Horsforth, Leeds, LS18 5HD, UK.
Department of Sport, Exercise and Rehabilitation, Northumbria University, Northumberland Road, Newcastle upon Tyne, UK.
Eur J Appl Physiol. 2018 Dec;118(12):2643-2654. doi: 10.1007/s00421-018-3987-8. Epub 2018 Sep 10.
Hot compared to cold drinks alter sweating responses during very low intensity exercise in temperate conditions. The thermoregulatory, perceptual, and performance effects of hot compared to cold drinks in hot, dry conditions during high-intensity exercise have not been examined.
Ten participants [mean ± SD characteristics age 25 ± 5 years, height 1.81 ± 0.07 m, body mass 73.5 ± 10.6 kg, maximal power output (P) 350 ± 41 W] completed two conditions, where they drank four boluses (ingested at - 9, 15, 30, and 45 min, respectively) of 3.2 mL kg (~ 960 mL total) of either a COLD (5.3 °C) or a HOT drink (49.0 °C), which were contrasted to a no-drink CONTROL. They cycled for 60-min [55% P in hot (34.4 °C) dry (34% RH)] ambient conditions followed by a test to exhaustion (TTE; 80% P). The thermoregulatory, performance, and perceptual implications of drink temperature were measured.
TTE was worse in the CONTROL (170 ± 132 s) than the COLD drink (371 ± 272 s; p = 0.021) and HOT drink conditions (367 ± 301 s; p = 0.038) which were not different (p = 0.965). Sweat responses [i.e., reflex changes in mean skin temperature (T) and galvanic skin conductance] indicated transient reductions in sweating response after COLD drink ingestion. The COLD drink improved thermal comfort beyond the transient changes in sweating.
Only COLD drink ingestion changed thermoregulation, but improved perceptual response. Accordingly, we conclude a role for gut thermoreception in thermal perception during exercise in hot, dry conditions.
与冷饮相比，在温带环境下进行极低强度运动时，热饮会改变出汗反应。在高温、干燥条件下进行高强度运动时，与冷饮相比，热饮对热调节、感知和表现的影响尚未被研究。
10 名参与者（平均特征年龄 25±5 岁，身高 1.81±0.07 米，体重 73.5±10.6 公斤，最大功率输出（P）350±41W）完成了两种条件，分别饮用了 4 次（分别在-9、15、30 和 45 分钟时摄入）4 个 boluses（3.2ml/kg（约 960ml 总量）的 COLD（5.3°C）或 HOT 饮料（49.0°C），与不喝饮料的 CONTROL 相比。他们在 55% P 的热（34.4°C）干燥（34%RH）环境条件下进行了 60 分钟的骑行，然后进行了 80% P 的最大耐受时间（TTE）测试。测量了饮料温度对热调节、性能和感知的影响。
TTE 在 CONTROL（170±132s）中比 COLD 饮料（371±272s；p=0.021）和 HOT 饮料条件（367±301s；p=0.038）更差，且这两种条件没有差异（p=0.965）。出汗反应[即平均皮肤温度（T）和皮肤电导的反射性变化]表明，COLD 饮料摄入后出汗反应短暂减少。COLD 饮料在出汗反应的短暂变化之外改善了热舒适度。
只有 COLD 饮料的摄入改变了热调节，但改善了感知反应。因此，我们得出结论，肠道热感受器在热、干燥条件下运动时的热感知中起作用。
