A landmark 47-year longitudinal study from the Karolinska Institute reveals that physical fitness peaks far earlier than conventional wisdom suggests—typically between the late teens and mid-30s. After age 40, the decline in aerobic capacity and muscle strength accelerates significantly, underscoring the importance of establishing exercise habits during youth.
However, the research offers encouraging news for those who begin fitness regimens later in life. Even individuals who start exercising after missing their peak years can achieve measurable improvements of 5–10% in physical capacity. This “physiological reserve” built through early activity serves as a protective buffer against age-related decline, maintaining functional health and independence across the lifespan.
The findings challenge the assumption that middle age offers a second chance for fitness without consequence. While it is never too late to exercise, starting early provides distinct long-term advantages.
Read the full article on GMJ Newsroom.
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