Body temperature regulation and circulatory response of persons with spinal cord injury during exercise in a hot environment.

本研究旨在探讨热环境下，脊髓损伤截瘫患者在进行摇臂运动时的体温调节特点。病变位于T3和L5之间的成年男性SCI和成年男性健全受试者（AB）参与了本研究。受试者暴露于高温（33℃）或中等温度（25℃）环境中1小时。在暴露的最后5或30分钟期间，受试者以40 W的运动强度进行手臂摇动运动5分钟或以20 W的运动强度进行30分钟。在实验期间连续监测身体的6个部位的皮肤温度、鼓膜温度、大腿皮肤血流量（SBFT）和心率。高位病变组（T3-T10）在安静和运动时的鼓膜温度和心率均高于低位病变组（T11-L5）。高位截瘫患者SBFT在33℃时保持不变，而低位截瘫患者在运动时SBFT持续增加，与AB相似。高位截瘫患者下肢交感血管功能受损，皮肤血流量在高温下无变化。高位病变截瘫患者的核心温度升高被认为是由于麻痹区域缺乏血管活性和汗液反应。根据本研究的结果，可以认为，高核心温度没有任何SBFT的增量可能是在热环境中运动时高位病变截瘫患者的身体热平衡的特点。

The purpose of this investigation was to clarify the characteristics of body temperature regulation in paraplegics due to spinal cord injury (SCI) during arm cranking exercise in a hot environment. Adult male SCI with lesions located between T3 and L5 and adult male able-bodied subjects (AB) participated in this study. The subjects were exposed to a hot (33℃) or a moderate temperature (25℃) environment for one hour. During the last 5 or 30 min of the exposure, the subject performed arm cranking exercises for 5 min at an exercise intensity of 40 W or for 30 min at 20 W.The skin temperature at six sites of the body, the tympanic membrane temperature, the skin blood flow of the thigh (SBFT), and heart rate were continuously monitored during the experiment. Paraplegics with high lesion (T3-T10) showed the higher tympanic membrane temperature and heart rate than those with low lesions (T11-L5) at rest and during exercise. SBFT of paraplegics with high lesion remained unchanged during the experiment at 33℃, while paraplegics with low lesions showed consecutive increases in SBFT during exercise similar to AB.In paraplegics with high lesions, who have impaired sympathetic vasomotor function in the lower limbs, skin blood flow is unchanged by exposure to a high temperature. The increased core temperature in paraplegics with high lesions was considered to be due to lack of a vasomotor activity and a sweat response in the paralyzed area. On the basis of the findings in this study, it can be suggested that high core temperature without any increment of SBFT may be characterized as body heat balance of paraplegics with high lesions during exercise in a hot environment.