대학 테니스 선수들의 여름계절 순화경험이 자발적 온열 부하에 대한 중추피로 감소에 미치는 효과

Abstract

The purpose of this study is to examine whether the summer seasonal acclimatization (SSA) experience improves the tolerance to central fatigue caused by thermal stress. In order to verify it, tympanic temperature (TYMP) was monitored as an index of core temperature and mean body temperature (mTb) was observed while passive heating and prolactin (PRL) which is an indirect biological marker of central serotonergic (5-HT) and dopaminergic (DA) activity was analyzed. Testing was performed in July (pre-SSA) and August (post-SSA) [(temperature, 26.84±1.35℃, relative humidity, 81.05±5.07% during SSA in Cheonan (126º52'N,33.38'E)]. All experiments were carried out in an automated climatic chamber (25.0±0.5℃, RH 60.0±3.0%). Twelve male volunteers who were well-trained college tennis players were recruited in this study(age, 22.50±2.73yrs, height, 175.30±5.80cm, weight, 66.14±5.28kg, body surface area, 1.83±0.15m^2). Passive heating method which takes leg immersion at warm water (43℃) for 30 min is applied. Results showed that TYMP and mTb after SSA were significantly lower (p<.05). It was confirmed that PRL was also significantly lower after SSA (p<.01). The fact which can be presented through this study is that the possibility in which the ratio of 5-HT / DA activity is significantly reduced after SSA under the condition of same thermal stress. The cause could be that the tolerance to the central fatigue caused by thermal stress is improved.