Related Experiment Video
Updated: Jan 11, 2026
08:36
Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments
Published on: August 8, 2019
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Circadian rest-activity rhythms and physical function in community-dwelling older men: The MrOS sleep study
Yujia Susanna Qiao1, Terri Blackwell1, Dorothy M Chen2
1Research Institute, California Pacific Medical Center, San Francisco, California, USA.
Sleep Health
|November 12, 2025
Summary
Weaker rest-activity rhythms (RARs) in older men are linked to declines in physical function, especially gait and chair stand speed. Improving RARs may help maintain physical function in aging populations.
Area of Science:
- Gerontology
- Chronobiology
- Physical Therapy
Background:
- Circadian rest-activity rhythms (RARs) are crucial for daily physical activity and sleep patterns.
- Declining physical function with age increases risks of disability and mortality.
- RARs are associated with cardiometabolic risk, fall risk, and cognitive decline.
Purpose of the Study:
- To investigate the association between rest-activity rhythms (RARs) and physical function in older men.
- To explore both cross-sectional and longitudinal relationships between RARs and physical function decline.
Main Methods:
- Utilized data from 2924 older men in the Osteoporotic Fractures in Men (MrOS) study.
- Assessed physical function via 6-meter gait speed, chair stand speed, and grip strength over a mean follow-up of 6.4 years.
- Quantified RARs using functional principal components analysis, parametric, and non-parametric approaches, analyzed with mixed-effects models.
Main Results:
- Reduced RAR strength (e.g., amplitude) and regularity were associated with poorer physical function, particularly gait and chair stand speed.
- Timing aspects of RARs showed cross-sectional associations with chair stand speed.
- Associations varied slightly by RAR quantification method and more significantly by physical function measure.
Conclusions:
- Rest-activity rhythms (RARs) are potential modifiable targets for interventions.
- Maintaining robust RARs may be key to preserving physical function, especially lower extremity function, in older adults.
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