Sex Differences in Strength & Size Adaptations to Resistance Training in Older Adults
Meta-analysis
Key Findings
30 studies (41 comparison groups), 1410 participants (651 men, 759 women) older than 50, men and women performing IDENTICAL resistance-training interventions; searched to June 2020; mean quality 14.7/29 (modified Downs and Black, moderate)
Relative lower-body strength: women gained MORE than men (g=−0.21, 95% CI −0.33 to −0.10, p=0.0003)
Relative upper-body strength: no sex difference (g=−0.29, 95% CI −0.62 to 0.04, p=0.08); relative muscle size: no difference (g=0.10, 95% CI −0.04 to 0.23, p=0.16)
Absolute gains: men gained more upper-body strength (g=0.48, 95% CI 0.09-0.88, p=0.016) and lower-body strength (g=0.33, 95% CI 0.19-0.47)
Authors' conclusion: sex differences in adaptation ARE apparent in older adults, but their interpretation depends heavily on whether results are presented in absolute or relative terms
Nuances by menopause — see REF-523 (postmenopausal women showed no hypertrophy at 6-8 sets/muscle/week)
Practical Application
Meta-analysis of 30 studies (1410 adults over 50) doing identical resistance training: women gained more relative lower-body strength than men (g=−0.21, p=0.0003), relative upper-body strength and muscle size did not differ, and men gained more in absolute terms (upper g=0.48, lower g=0.33). Women do not adapt less — they start lower in absolute terms.
For a coach of female athletes: apply the same volume/frequency principles (REF-513/514), not "lightened" versions; expect equal or better relative progress
Age modification (postmenopause) — via volume, not via changing principles (REF-523)
Inference, not tested here: the older-adult sample is the strongest available sex comparison; transfer to young female athletes is indirect
Limitations
The meta-sample is adults older than 50; transfer to young female athletes is indirect
Study quality moderate (14.7/29); absolute vs relative effects require careful interpretation
Protocol heterogeneity
How this entry was checked and changed
Content correction 2026-09-27
"Relative (%) adaptations are broadly comparable between sexes" -> the abstract reports women gained MORE relative lower-body strength (g=−0.21, p=0.0003); upper-body strength and muscle size were comparable; men gained more absolutely. Direction corrected and numbers added (30 studies, 41 groups, n=1410, 651 M/759 F, quality 14.7/29).
Sport "cycling, running, rowing" -> "strength" (resistance-training meta-analysis); Tier "mixed" -> Tier 0-2 (adults over 50).