| Keywords |
피부온도 초기하강 ; 트래드밀 운동 ; 간헐적 인체 냉각 ; 손가락 온도 Initial fall in skin temperature ; Treadmill exercise ; Intermittent regional cooling ; Finger temperature |
| Abstract |
The present study was designed to observe the thermal dynamics of core and skin temperatures during submaximal treadmill exercise; to investigate the effect of regional body cooling during short rest after the treadmill exercise on the thermal dynamics. Three conditions (No cooling, Head/Hand cooling, Leg cooling) were simulated in a climatic chamber at 24±1oC and 50±5%RH. Subjects performed two bouts of treadmill exercise at a rate of 80%HRmax followed by rest. Body cooling with a hood, long gloves, and a blanket that circulated water set at 15oC was assigned during two bouts of rest. The results showed that (1) rectal temperature (Tre) did not show significant difference between three conditions; (2) Skin temperatures had specific features, depending on body regions. In particular, the initial fall phenomena of skin temperatures at the onset of exercise were noteworthy in the chest, thigh, calf, and finger tip. Of these, the most significant initial fall was found in finger temperature (Tfing). (3) During the period of the initial fall in skin temperatures, Tre gradually increased. (4) The magnitude of the fall of Tfing at the onset of 2nd running was on average 4.8, 5.1 and 3.4oC for Control, HH cooling, and Leg cooling, respectively (p<0.05). The initial drop of Tfing at the onset of running was maintained for an average of 8.1, 7.9 and 6.3 minutes for Control, HH cooling, and Leg cooling, with no significant differences. In conclusion, the initial fall phenomena at the onset of treadmill exercise reflected non-thermal factors, as opposed to internal thermal status. The magnitude of the initial fall in Tfing was affected by legs cooling. Therefore, the initial fall phenomenon should be considered when interpreting the thermal status of the shell during heavy works/exercises that assigned with intermittent regional body cooling. |