Related Experiment Video
Updated: Jul 25, 2026
08:21
Non-invasive Assessments of Subjective and Objective Recovery Characteristics Following an Exhaustive Jump Protocol
Published on: June 8, 2017
Age-related differences in recovery from simulated jet lag
M L Moline1, C P Pollak, T H Monk
1Institute of Chronobiology, New York Hospital-Cornell Medical Center, White Plains.
Sleep
|February 1, 1992
Summary
Middle-aged men struggle more with early morning schedule shifts than younger men, experiencing greater sleep disruption and fatigue. This suggests age-related difficulties in maintaining sleep during early circadian times.
Area of Science:
- Chronobiology
- Sleep Science
- Human Physiology
Background:
- Circadian rhythms regulate sleep-wake cycles and physiological processes.
- Age can influence the ability to adapt to environmental and social time cues.
- Understanding age-related differences in circadian adaptation is crucial for public health.
Purpose of the Study:
- To investigate age-related differences in human circadian rhythm adjustment to a simulated 6-hour advance sleep-wake schedule shift.
- To assess the impact of this shift on sleep patterns, subjective well-being, and performance in young versus middle-aged men.
Main Methods:
- Healthy young and middle-aged men were isolated from time cues for 15 days.
- A 6-hour advance schedule shift was implemented after a baseline period.
- Sleep, meal times, core body temperature, and subjective alertness/well-being were monitored.
Main Results:
- Middle-aged men exhibited increased wakefulness during sleep and earlier sleep termination post-shift compared to young men.
- Middle-aged subjects reported greater decreases in alertness and well-being, and increased sleepiness and fatigue.
- Circadian core temperature rhythm adjustment rates were similar between age groups.
Conclusions:
- Middle-aged individuals experience more significant sleep maintenance issues and subjective distress following an eastward schedule shift.
- Difficulty maintaining sleep at biologically early times may explain the heightened symptoms in middle-aged men.
- Compensatory responses to sleep disruption may be less effective in middle-aged populations.
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