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Is it harder to stay fit as you get older? The science of aging and exercise.

According to the National Institute on Aging, adults can lose 3–5% of their muscle mass each decade after age 30, a condition known as sarcopenia. This physiological reality is one of the key reasons why people often wonder, **is it harder to stay fit as you get older?** The simple answer is yes, but understanding the underlying causes is the first step toward effective management and lasting health.