What is sarcopenia?
Sarcopenia is the gradual loss of muscle mass, strength and function with age, to the point where it starts to affect everyday life.
Think of your muscles as your body's savings account. Through midlife the balance slowly drains unless you keep making deposits. Sarcopenia is when the balance gets low enough that everyday expenses, like climbing stairs or carrying shopping, start to bounce.
Why it matters for aging
Muscle is much more than strength or looks. It's the biggest home for mitochondria in your body, the main place your blood sugar goes after a meal, and a protein reserve your body draws on when you're ill. Losing it affects energy, metabolism and independence.
Sarcopenia is linked to falls, fractures, frailty and loss of independence in later life. It often develops quietly, because the loss is slow and easy to mistake for "just getting older." Simple checks such as grip strength or how easily you can rise from a chair are often used to spot it.
The main lever is resistance training. Getting enough protein helps you get more out of it, but on its own it can't replace the training signal.
A common myth
Losing muscle is just part of getting older and there's not much you can do about it.
Muscle responds to training at any age. In a meta-analysis of 47 studies, older adults who did resistance training gained roughly a quarter to a third more strength, with higher-intensity programs working best. It's never too late to make deposits.
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Updated Nov 7, 2026 · All terms