Greater muscle mass is associated with improved longevity, disease resistance, and functional capacity in aging populations.

Study: Comparative effectiveness of progressive moderate- to high-intensity peripheral and inspiratory muscle training combined with aerobic exercise in community-dwelling older adults: A randomized clinical trial

People who did leg and arm exercises got stronger, walked farther, and felt better overall—this suggests having more muscle helps older adults live better and stay healthier longer.

Study: Skeletal and cardiac muscle longitudinal associations in the Baltimore Longitudinal Study of Aging (BLSA)

People who lose muscle faster as they age also tend to lose heart muscle faster, which can lead to worse health. So having more muscle likely helps people stay healthier and live longer.

Study: Frailty and sarcopenia as independent predictors of early functional recovery in older adults with osteoporotic vertebral compression fractures: a retrospective cohort study

Older people with less muscle mass had worse mobility, more pain, and stayed in the hospital longer after a fracture — meaning having more muscle helps you recover better and stay healthier as you age.

Study: Intracellular Water Content in Lean Mass is Associated with Muscle Strength, Functional Capacity, and Frailty in Community-Dwelling Elderly Individuals. A Cross-Sectional Study

People with more hydrated, healthy muscle cells tend to be stronger, move better, and are less likely to become frail as they age — even if their overall muscle size is the same as others.