Physical Capacity Decline Begins Decades Before Sarcopenia

LONGITUDINAL data demonstrate that physical capacity decline begins before age 40, accelerating toward substantial sarcopenia risk. In a population-based cohort of 427 participants evaluated across nearly five decades from age 16 to 63, objective functional assessments revealed that physical performance follows a constitutive trajectory. Peak muscular endurance and aerobic capacity occurred between ages 26 and 36, whereas muscular power peaked as early as age 19 in women and age 27 in men. Following these peaks, functional capacity entered a progressive decline that initiated at modest rates of 0.3% to 0.6% annually before accelerating to over 2.0% per year by the seventh decade of life.

Trajectories of Physical Capacity Decline Across Adulthood

Cumulative functional loss reached 30% to 48% from peak performance to age 63 across upper-body muscular endurance, lower-limb power, and cardiorespiratory fitness. Relative rates of decline followed comparable curves in both sexes, indicating that physical capacity decline reflects an innate biological aging trajectory rather than sex-specific divergence. Notably, inter-individual variance in physical performance expanded dramatically over time, showing a 25-fold increase in relative aerobic capacity variance and a nearly fivefold increase in muscular power variance by age 63. This widening divergence underscores that while aging universally limits maximum physiological potential, individual functional trajectories remain highly heterogeneous throughout life, carrying implications for systemic vulnerability across chronic rheumatic disease states.

Clinical Implications for Musculoskeletal and Sarcopenia Management

For rheumatologists and musculoskeletal specialists managing osteoarthritis and mobility preservation, these findings offer vital prognostic context. Skeletal muscle function directly protects articular structures, yet clinical sarcopenia evaluations often occur only after overt physical disability manifests. In this cohort, four women and zero men fell below standard clinical cutoffs for sarcopenia at age 63 on handgrip or chair stand assessments, despite significant preceding musculoskeletal losses. Importantly, engaging in leisure-time physical activity in adolescence, or adopting exercise during adulthood, conferred measurable gains across all modalities, including an 11% increase in muscular endurance and up to 7% in aerobic capacity. Clinicians should prioritize proactive resistance and aerobic regimens during midlife to build functional reserves before accelerated physical capacity decline compromises musculoskeletal health.

Reference

Westerståhl M et al. Rise and Fall of Physical Capacity in a General Population: A 47-Year Longitudinal Study. J Cachexia Sarcopenia Muscle. 2025;16:e70134.