Time memory for heat exposure and exercise limited to a fixed daily time in humans.

人类对热暴露和运动的时间记忆仅限于每天固定的时间。

• 批准号: 13680061
• 负责人: HIRASHITA Masami
• 金额: $ 1.66万
• 依托单位: Kinjo University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13680061/
• 关键词: Heat-acclimation; Core temperature; VO_2max; AT; Sweat rate; Exercise; Hc; Hot environment; サーカディアンリズム; 体温調節反応; V-slope法; トレーニング; 短期暑熱馴化; peakVo_2; 体液量

After daily heat exposure or exercise for 4-5 h limited to a fixed time for more than 5 consecutive days, body core temperature of rats drops before and during the period they were previously exposed to heat. To investigate the influence of exposure to heat or exercise performance, we measured the changes of hematological status, anaerobic threshold (AT : V-slope), maximal oxygen consumption (VO_2max), and sweat rate during exercise in long distance student runners before and after continuous heat exposure at tropical regions (Thailand). And after the core temperature is regard as oral temperature, when they wake up, their basal body temperature were measured. After then, they were measured 5 times everyday (before a breakfast, at resting time before and after an exercise, before a dinner, and before going to bed). The amount of sweat during exercise is measured as a sweat loss with the following equation. Sweat loss = (weight before during exercise + weight of drinking water) - weight … More after the exercise. The ambient temperature is measured with WBGT with a heat environment checker (Kyoto Electronics Manufacturing Co.,Ltd).Changes in basal and resting core temperature (Tcor) during 12 experimental days in hot environmentIn the case of staying in Japan, Tcor kept about 35.9℃ and in the case of Thailand, the Tcor shifted to the neighborhood of 36.4℃. After they came back to Japan, the Tcor kept 36.3℃ on the second day. In staying in Japan, the Tcor of resting after an exercise was always lower than that of resting before an exercise. On the other hand and in the case of Thailand, the result was opposite. Thus, our human basal temperature may be rise by repeating exercise in hot environment.Although the sweat rate during exercise showed about 700g/h under cold environment of Japan, the sweat rate increased largely until the 5th day after the participant moved to Thailand, it decreased a little and kept about 1400g/h. When the subjects were 2 hour exercising in winter in Japan, the amount of drinking water was not observed, but the amount kept about 500g/h in Thailand. These result suggested that the raising of basal temperature after repeating exercise in hot environment is caused by dehydration.The difference of physiological responses between pre- and post- heat exposure during maximal exercise, sweat rate during maximum exercise after 12 heat exposure.The hematological data (RBC, Ht) and heart rate were significantly lower before heat-acclimation than after heat-acclimation. VO_2max and sweat rate were significantly higher before heat-acclimation than after heat-acclimation. These results indicate that maximal aerobic power may be increased by consecutive heat exposure. And this increased exercise performance is caused by plasma and blood volume. Less

每日热暴露或连续5天以上固定时间运动4 ~ 5小时后，大鼠在热暴露前和热暴露期间的体核温度下降。为了研究热暴露对运动表现的影响，我们在热带地区（泰国）测量了长跑学生运动员在连续热暴露前后的血液学状态、无氧阈值（AT: V-slope）、最大耗氧量（VO_2max）和排汗率的变化。将核心体温作为口腔体温后，在受试者醒来时测量其基础体温。之后，每天测量5次（早餐前、运动前后休息时间、晚餐前、睡觉前）。运动时的出汗量是用下面的公式来衡量的。排汗=（运动前的体重+饮水的体重）-运动后的体重…使用带热环境检测器（京都电子制造有限公司）的WBGT测量环境温度。高温环境下12天实验的基础和静息核心温度（Tcor）变化：在日本停留时，Tcor保持在35.9℃左右，在泰国停留时，Tcor移至36.4℃附近。回到日本后，第二天温度保持在36.3℃。在日本逗留期间，运动后休息的Tcor总是低于运动前休息的Tcor。另一方面，在泰国的情况下，结果正好相反。因此，我们的人体基础体温可能会通过在高温环境中反复运动而升高。虽然在日本寒冷环境下，运动时的排汗率约为700g/h，但到泰国后第5天，运动时的排汗率大幅上升，之后略有下降，保持在1400g/h左右。在日本冬季运动2小时时，不观察饮水量，而在泰国则保持在500g/h左右。上述结果提示，高温环境下反复运动后基础体温升高是由脱水引起的。热暴露前后最大运动时生理反应的差异，热暴露后最大运动时的排汗率。血液学指标（RBC、Ht）和心率在热驯化前显著低于热驯化后。热驯化前的VO_2max和出汗率显著高于热驯化后。这些结果表明，连续的热暴露可以增加最大有氧能力。这种运动表现的提高是由血浆和血容量引起的。少

项目成果

"Thermoregulatory responses during heat load and isometric exercise in hot environment."Kinjo University Bulletin. 3. 107-115 (2003)

“热负荷和热环境中等长运动期间的体温调节反应。”金城大学通报。

Yoko KAJIWARA, Seiichi NAKAI, Masami HIRASHITA: "Environmental temperature and thermoregulatory responses in children during baseball practice in summer."The Fourth ICHPER. SD Asia Congress Proceedings. 4. 79-84 (2003)

Yoko KAJIWARA、Seiichi NAKAI、Masami HIRASHITA：“夏季棒球练习期间儿童的环境温度和体温调节反应。”第四届 ICHPER。

平下政美: "持久的運動鍛錬の違いによる下半身陰圧負荷時循環調節反応"金城大学紀要. 第2号. 123-130 (2002)

平下正美：“由于耐力运动训练的差异而导致的下半身负压负荷时的循环控制反应”金城大学通报第 2. 123-130 号（2002 年）。

平下政美: "短期暑熱馴化による運動時発汗量の変化"体力科学. 51巻・6号. 682 (2002)

Masami Hirashita：“由于短期热适应而导致的运动过程中的出汗量变化”《体能科学》，第 51 卷，第 6.682 期（2002 年）。

平下政美: "高温環境下における体温上昇時の局所作業時体温調節反応"金城大学紀要. 第3号. 107-115 (2003)

平下雅美：“高温环境下体温升高时局部工作时的体温调节反应”金城大学公报第 3. 107-115 号（2003 年）。