Longevity & AgingFrailty Is Far More Than Muscle Loss — A New Biopsychosocial Model Redefines It
For decades, frailty was defined almost entirely by physical markers — slow gait, muscle weakness, and unintentional weight loss. A major 2026 review in Clinical Geriatrics Medicine argues that frailty is far broader: a multidimensional biopsychosocial syndrome encompassing cognitive, social, and psychological dimensions alongside the physical. The authors survey updated definitions for each domain, the assessment tools clinicians use to detect them, epidemiological data on how common each type is, what drives them at a biological and social level, and current frameworks for prevention and treatment. The expansion of frailty's definition has drawn social and behavioral scientists into a field once dominated by geriatricians, opening new avenues for intervention. Understanding frailty's full scope is essential for anyone aiming to extend not just lifespan but genuine functional independence into old age.
