Research

Mixed

Class II sarcopenia (skeletal muscle index more than 2 standard deviations below young adult mean) is independently associated with a significantly increased likelihood of functional impairment and physical disability in older adults, particularly women.

If you are over 60, your muscle mass relative to your body weight matters significantly for your ability to perform daily tasks. Severe muscle loss (Class II sarcopenia) doubles or triples your risk of disability. Focus on maintaining or building muscle through resistance exercise, as this is a key factor in preserving independence and functional ability in later life.

GoodSupportsHIGH confidence
The likelihood of functional impairment and disability was approximately two times greater in the older men and three times greater in the older women with class II sarcopenia than in the older men and women with a normal SMI, respectively.
Ian Janssen et al. · Journal of the American Geriatrics Society · 2002

Why this rating

Large, nationally representative cross-sectional study (NHANES III) with rigorous adjustment for confounders, though causality is limited by cross-sectional design.

Source

Low Relative Skeletal Muscle Mass (Sarcopenia) in Older Persons Is Associated with Functional Impairment and Physical Disability

Ian Janssen et al. · Journal of the American Geriatrics Society · 2002

DOI 10.1046/j.1532-5415.2002.50216.x

cross_sectional · n=4504Cited 3,143×
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DOI resolved against Crossref · corpus check 2026-06-10

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