Research

Hormonal

Exercise-induced circadian phase shifts are not significantly different between young adults (18-30 years) and older adults (59-75 years), nor between men and women.

You do not need to adjust your exercise timing strategy based on your age or sex to achieve circadian phase shifts. The same timing principles apply to older adults as they do to younger adults.

GoodSupportsHIGH confidence
There were no significant age or sex differences.
Shawn D. Youngstedt et al. · The Journal of Physiology · 2019

Why this rating

Robust study design with sufficient sample size (n=101) to detect differences if they existed.

Source

Human circadian phase–response curves for exercise

Shawn D. Youngstedt et al. · The Journal of Physiology · 2019

DOI 10.1113/jp276943

crossover · n=99Cited 248×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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