A 47-Year Study Reveals the Exact Age Strength Starts Declining—and It’s Earlier Than You Think

As we age, muscles naturally weaken, and even simple, everyday tasks become more challenging without consistent movement. Losing muscle mass and strength can affect your independence, mobility, and overall health over time. And now, as if you needed another reason to exercise, a recent study found that muscle decline often starts well before age 40.

The Swedish study, published in the Journal of Cachexia, Sarcopenia and Muscle, followed several hundred people for 47 years, tracking their strength, endurance, and aerobic fitness.