PHASE RESPONSE CURVES FOR EXERCISE AND BRIGHT LIGHT

描述（改编自研究者摘要）：研究者的 实验室发现了一个令人震惊的普遍不同步的 平均年龄70岁的志愿者的昼夜节律。老年人可能 对强光的昼夜同步效应有异常抵抗力。 如果是这样的话，我们可能需要开发替代方法， 使它们的昼夜节律与环境同步。最近的研究表明 运动可能会改变年轻人的昼夜节律，但目前还不清楚 关于锻炼对调节衰老中的昼夜节律的价值 人口似乎至关重要的是要扩大我们的理解运动的影响， 昼夜节律系统，特别是，比较潜在的价值， 运动和明亮的光线，以纠正昼夜节律不同步， 美国老人该项目将建立昼夜相位响应曲线 96名志愿者，年龄在18-30岁之间，加上128岁， 60-75岁的老年志愿者。志愿者将被记录为4.8至4.6 在极短的睡眠-觉醒周期（包括30分钟）后， 然后是60分钟的清醒时间基线昼夜节律时相 尿6-硫酸氧褪黑激素、尿游离皮质醇、体温和睡眠 将每90分钟评估一次倾向性。将对口腔温度进行采样 每30分钟一次。志愿者将接受实验性的相移治疗 （运动或明亮的光线）3天。由此产生的昼夜节律阶段将是 确定计算相位响应曲线，以检查 刺激（运动与光照）、年龄和性别对昼夜节律的相互作用 响应能力。

DESCRIPTION (adapted from investigator's abstract): The investigator's laboratory has discovered an appalling prevalence of malsynchronization of circadian rhythms among volunteers averaging 70 years of age. Aging people may be abnormally resistant to the circadian synchronizing effects of bright light. If so, we may need to develop alternative methods by which older Americans can synchronize their circadian rhythms to the environment. Recent studies indicate that exercise may shift circadian rhythms in young adults, but nothing is known about the value of exercise for regulating circadian rhythms in the aging population. It seems crucial to extend our understanding of exercise effects on the circadian system and, specifically, to compare the potential values of exercise and bright light for correcting the circadian malsynchronization of older Americans. The project will establish circadian phase response curves both for exercise and for bright light in 96 volunteers, ages 18-30 plus 128 older volunteers ages 60-75 years. Volunteers will be recorded for 4.8 to 4.6 days while following an ultra-short sleep-wake cycle, consisting of 30 minutes for sleeping, followed by 60 minutes for waking. Baseline circadian phases of urinary 6-sulphatoxymelatonin, urinary free cortisol, temperature and sleep propensity will be assessed every 90 min. Oral temperature will be sampled every 30 min. Volunteers will be given experimental phase-shifting treatments (exercise or bright light) for 3 days. Resultant circadian phases will then be determined to compute the phase response curves, in order to examine interactions of stimulus (exercise vs. light), age, and gender on circadian responsiveness.