Naito Takashi, Iribe Yuka, Ogaki Tetsuro
Graduate School of Human-Environment Studies, Kyushu University, 6-1 Kasuga-koen, Kasuga-City, Fukuoka, 816-8580, Japan.
J Physiol Anthropol. 2017 Jan 5;36(1):9. doi: 10.1186/s40101-016-0122-6.
The timing in which ice before exercise should be ingested plays an important role in optimizing its success. However, the effects of differences in the timing of ice ingestion before exercise on cycling capacity, and thermoregulation has not been studied. The aim of the present study was to assess the effect of length of time after ice ingestion on endurance exercise capacity in the heat.
Seven males ingested 1.25 g kg body mass of ice (0.5 °C) or cold water (4 °C) every 5 min, six times. Under three separate conditions after ice or water ingestion ([1] taking 20 min rest after ice ingestion, [2] taking 5 min rest after ice ingestion, and [3] taking 5 min rest after cold water ingestion), seven physically active male cyclists exercised at 65% of their maximal oxygen uptake to exhaustion in the heat (35 °C, 30% relative humidity).
Participants cycled significantly longer following both ice ingestion with a long rest interval (46.0 ± 7.7 min) and that with a short rest interval (38.7 ± 5.7 min) than cold water ingestion (32.3 ± 3.2 min; both p < 0.05), and the time to exhaustion was 16% (p < 0.05) longer for ice ingestion with a long rest interval than that with a short rest interval. Ice ingestion with a long rest interval (-0.55 ± 0.07 °C; both p < 0.05) allowed for a greater drop in the core temperature than both ice ingestion with a short rest interval (-0.36 ± 0.16 °C) and cold water ingestion (-0.11 ± 0.14 °C). Heat storage under condition of ice ingestion with a long rest interval during the pre-exercise period was significantly lower than that observed with a short rest interval (-4.98 ± 2.50 W m; p < 0.05) and cold water ingestion (2.86 ± 4.44 W m).
Therefore, internal pre-cooling by ice ingestion with a long rest interval had the greatest benefit on exercise capacity in the heat, which is suggested to be driven by a reduced rectal temperature and heat storage before the start of exercise.
运动前摄入冰块的时间对于优化其效果起着重要作用。然而，运动前不同时间摄入冰块对骑行能力和体温调节的影响尚未得到研究。本研究的目的是评估摄入冰块后时间长短对高温环境下耐力运动能力的影响。
七名男性每5分钟摄入1.25克/千克体重的冰块（0.5°C）或冷水（4°C），共六次。在摄入冰块或水后的三种不同条件下（[1]摄入冰块后休息20分钟，[2]摄入冰块后休息5分钟，[3]摄入冷水后休息5分钟），七名身体活跃的男性自行车运动员在高温环境（35°C，相对湿度30%）下以最大摄氧量的65%进行运动直至力竭。
与摄入冷水（32.3±3.2分钟）相比，摄入冰块后长时间休息间隔（46.0±7.7分钟）和短时间休息间隔（38.7±5.7分钟）后参与者的骑行时间显著更长（均p<0.0
