Ichimura Shiro, Murase Norio, Osada Takuya, Kime Ryotaro, Homma Toshiyuki, Ueda Chihoko, Nagasawa Takeshi, Motobe Mayuko, Hamaoka Takafumi, Katsumura Toshihito
Department of Liberal Arts, Faculty of Science and Technology, Tokyo University of Science, Chiba, Japan.
Med Sci Sports Exerc. 2006 Jul;38(7):1277-81. doi: 10.1249/01.mss.0000227312.08599.f1.
The purpose of this study was to determine the interaction of age and habitual physical activity on recovery time of muscle oxygenation following maximal cycling exercise (CycEXmax).
Twelve sedentary middle-aged (50+/-6), 13 sedentary elderly (66+/-3), 13 active middle-aged (53+/-5), and 20 active elderly (67+/-5) women participated in this study. We evaluated the peak pulmonary oxygen uptake (VO2peak) during CycEXmax and the half-recovery time of muscle oxygenation (T1/2reoxy time) using near-infrared spectroscopy at the vastus lateralis (VL) during the recovery phase after CycEXmax.
T1/2reoxy time was significantly greater in the elderly subjects than in the middle-aged subjects in both sedentary (P<0.05) and active groups (P<0.01). T1/2reoxy time of the active group was lower (P<0.01) than that of the sedentary group regardless of age. Age was significantly correlated to T1/2reoxy time in both sedentary and active groups (in both sedentary and active groups: P<0.01). The slope of T1/2reoxy time against age in the sedentary group was significantly greater (VL: P<0.05) than that of the active group. VO2peak showed significant inverse correlation with T1/2reoxy time at the VL in both sedentary and active groups. The slope of VO2peak against T1/2reoxy time showed no significant differences between middle-aged and elderly subjects.
The results of this study suggest that T1/2reoxy time was prolonged with aging, regardless of habitual physical activity levels. However, habitual physical activity may prevent the age-related prolongation in T1/2reoxy time after CycEXmax. VO2peak appears to be one of the major factors determining T1/2reoxy time, not age.
本研究旨在确定年龄与习惯性身体活动对最大强度骑行运动（CycEXmax）后肌肉氧合恢复时间的相互作用。
12名久坐不动的中年女性（50±6岁）、13名久坐不动的老年女性（66±3岁）、13名经常运动的中年女性（53±5岁）和20名经常运动的老年女性（67±5岁）参与了本研究。我们评估了CycEXmax期间的峰值肺摄氧量（VO2peak），以及在CycEXmax后的恢复阶段，使用近红外光谱法在股外侧肌（VL）测量肌肉氧合的半恢复时间（T1/2reoxy时间）。
在久坐不动组（P<0.05）和经常运动组（P<0.01）中，老年受试者的T1/2reoxy时间均显著长于中年受试者。无论年龄如何，经常运动组的T1/2reoxy时间均低于久坐不动组（P<0.01）。在久坐不动组和经常运动组中，年龄均与T1/2reoxy时间显著相关（久坐不动组和经常运动组均为：P<0.01）。久坐不动组中T(_{1/2})reoxy时间随年龄变化的斜率显著大于经常运动组（VL：P<0.05）。在久坐不动组和经常运动组中，VO2peak与VL处的T1/2reoxy时间均呈显著负相关。中年和老年受试者的VO2peak随T1/2reoxy时间变化的斜率无显著差异。
本研究结果表明，无论习惯性身体活动水平如何，T1/2reoxy时间都会随着年龄增长而延长。然而，习惯性身体活动可能会防止CycEXmax后T1/2reoxy时间出现与年龄相关的延长。VO2peak似乎是决定T1/2reoxy时间的主要因素之一，而非年龄。
