Waterhouse Jim, Drust Barry, Weinert Dietmar, Edwards Benjamin, Gregson Warren, Atkinson Greg, Kao Shaoyuan, Aizawa Seika, Reilly Thomas
Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UK.
Chronobiol Int. 2005;22(2):207-25. doi: 10.1081/cbi-200053477.
This review first examines reliable and convenient ways of measuring core temperature for studying the circadian rhythm, concluding that measurements of rectal and gut temperature fulfil these requirements, but that insulated axilla temperature does not. The origin of the circadian rhythm of core temperature is mainly due to circadian changes in the rate of loss of heat through the extremities, mediated by vasodilatation of the cutaneous vasculature. Difficulties arise when the rhythm of core temperature is used as a marker of the body clock, since it is also affected by the sleep-wake cycle. This masking effect can be overcome directly by constant routines and indirectly by "purification" methods, several of which are described. Evidence supports the value of purification methods to act as a substitute when constant routines cannot be performed. Since many of the mechanisms that rise to the circadian rhythm of core temperature are the same as those that occur during thermoregulation in exercise, there is an interaction between the two. This interaction is manifest in the initial response to spontaneous activity and to mild exercise, body temperature rising more quickly and thermoregulatory reflexes being recruited less quickly around the trough and rising phase of the resting temperature rhythm, in comparison with the peak and falling phase. There are also implications for athletes, who need to exercise maximally and with minimal risk of muscle injury or heat exhaustion in a variety of ambient temperatures and at different times of the day. Understanding the circadian rhythm of core temperature may reduce potential hazards due to the time of day when exercise is performed.
本综述首先探讨了用于研究昼夜节律的可靠且便捷的核心体温测量方法，得出结论：直肠温度和肠道温度测量满足这些要求，但腋下隔热温度测量则不然。核心体温昼夜节律的起源主要归因于通过四肢散热速率的昼夜变化，这由皮肤血管舒张介导。当将核心体温节律用作生物钟标志物时会出现困难，因为它也受睡眠 - 觉醒周期的影响。这种掩盖效应可通过固定作息直接克服，也可通过“纯化”方法间接克服，本文描述了其中几种方法。有证据支持在无法进行固定作息时，纯化方法可作为替代方法的价值。由于许多导致核心体温昼夜节律的机制与运动中体温调节时的机制相同，所以二者之间存在相互作用。这种相互作用在对自发活动和轻度运动的初始反应中表现出来，与静息体温节律的峰值和下降阶段相比，在低谷和上升阶段，体温上升更快，体温调节反射的启动更慢。这对运动员也有影响，他们需要在各种环境温度和一天中的不同时间进行最大强度的运动，同时将肌肉损伤或热衰竭的风险降至最低。了解核心体温的昼夜节律可能会降低因运动时间而产生的潜在危害。
