The Copenhagen Sarcopenia Study: lean mass, strength, power, and physical function in a Danish cohort aged 20-93 years.
Level 4 - case-series / case-control
Cross-sectional population-based observational study.
PubMed 31419087 · doi:10.1002/jcsm.12477
What was done
A cross-sectional study of 1,305 healthy volunteers aged 20–93 years (729 women, mean age 56.4 ± 18.9 years; 576 men, mean age 57.0 ± 17.5 years) drawn from the Copenhagen City Heart Study. Researchers measured lean mass using dual-energy X-ray absorptiometry (total lean mass, appendicular lean mass [ALM], and ALM adjusted for height squared [ALM/h²]), muscle strength and power (Jamar handgrip strength, Nottingham leg extension power), and functional performance (30-second sit-to-stand test, 10-meter habitual and maximal gait speed) to establish normative reference values across the adult lifespan.
What was found
Total lean mass, ALM, and ALM/h² decreased with age in both sexes (P < 0.001), with men maintaining higher absolute and relative ALM, handgrip strength, and leg extension power than women across all age groups (P < 0.001). Handgrip strength and leg extension power declined progressively with age (P < 0.01). Power-based metrics (leg extension power and 30-second sit-to-stand) began declining earlier, showing significant reductions from age 50 onward compared with young controls (P < 0.001). Maximal gait speed decreased from age 60 (P < 0.001), whereas habitual gait speed, handgrip strength, and lean mass parameters remained relatively preserved until age 70 and older (P < 0.001).
Why it matters
This study provides population-specific normative reference data for muscle mass, power, and physical performance across adulthood. It highlights that functional muscle power declines decades before detectable reductions in gross muscle mass or standard isometric grip strength.
Limits
The cross-sectional design cannot measure individual rates of decline or establish causal trajectories over time. The cohort was restricted to healthy Danish volunteers, limiting generalizability to other ethnicities, geographic regions, or clinical populations with chronic comorbidities.
Cited by
- context Muscle mass begins to decline starting in a person's 30s if left unaddressed.