Ohkuwa T, Itoh H, Yamamoto T, Yanagi H, Yamazaki Y, Akimaru T
Department of General Studies, Nagoya Institute of Technology, Nagoya, Showa-ku, Japan.
Arch Physiol Biochem. 2001 Dec;109(5):430-4. doi: 10.1076/apab.109.5.430.8034.
This study was designed to examine the effect of exposure to two levels of light intensity (bright; 5000 lux, dim; 50 lux) prior to supramaximal cycle exercise on performance and metabolic alterations. The exercise was performed after bright and dim light exposure for 90 minutes. Ten male long-distance runners volunteered to take part in the study. They performed 45-sec supramaximal exercise using a cycle ergometer in a 500-lux. Mean power output was measured during the exercise. Lactate and ammonia in the blood and epinephrine and norepinephrine concentrations in plasma were measured at rest immediately after bright and dim light exposures and after the exercise. Bright and dim light exposure prior to exercise did not significantly affect the power output during the exercise. Blood glucose concentration immediately after exercise and plasma epinephrine during the resting period were significantly lower after bright light exposure compared with dim light exposure (p < 0.05). No significant difference was found in blood lactate, ammonia, or plasma norepinephrine levels after exercise following bright and dim light exposures. This study demonstrated that bright light stimulation prior to supramaximal exercise decreases glucose and epinephrine levels, but is not related to physical performance.
本研究旨在探讨在进行极限强度自行车运动前，暴露于两种光照强度水平（明亮；5000勒克斯，昏暗；50勒克斯）对运动表现和代谢变化的影响。在明亮和昏暗光照下暴露90分钟后进行运动。十名男性长跑运动员自愿参与本研究。他们在500勒克斯环境下使用自行车测力计进行45秒的极限运动。运动过程中测量平均功率输出。在明亮和昏暗光照暴露后以及运动后立即静息状态下，测量血液中的乳酸和氨以及血浆中的肾上腺素和去甲肾上腺素浓度。运动前的明亮和昏暗光照暴露对运动过程中的功率输出没有显著影响。与昏暗光照暴露相比，明亮光照暴露后运动后即刻的血糖浓度和静息期的血浆肾上腺素显著降低（p<0.05）。明亮和昏暗光照暴露后运动后的血乳酸、氨或血浆去甲肾上腺素水平没有显著差异。本研究表明，极限运动前的明亮光照刺激会降低血糖和肾上腺素水平，但与运动表现无关。
