事前運動が最大強度運動時における２つの筋脱酸素化パラメータに及ぼす影響

Abstract

The purpose of this study was to investigate that the effects of prior exercise on two muscle deoxygenation parameters during maximal exercise were different. Seven active male volunteers (24±3 years) performed a heavy intermittent exercise test, composed of a 1-min maximal exercise (M-1), a 6-min exercise at the intensity of 65-70% of maximal oxygen uptake, and a 1-min maximal exercise (M-2), separated by 4-min rests. The changes of deoxygenated hemoglobin and myoglobin (d-HHb) and tissue oxygen saturation (d-StO2), assessed by near-infrared continuous-wave and spatially-resolved spectroscopies, respectively, were monitored from the vastus lateralis continuously. The d- HHb increased and the d-StO2 decreased during both M-1 and M-2 exercises. Compared to the M-1 exercise, d-StO2 was higher throughout the M-2 exercise (P＜0.01), but not d-HHb (N.S.). These results suggest that, during 1-min maximal exercise, the d-StO2 was partially attenuated by the prior exercise-induced vasodilation, but not the d-HHb.