Can exercise really prevent muscle loss as we age?

How exercise fights age-related muscle loss: The science behind stronger muscles

Muscle loss is a natural part of aging, starting around age 30 when adults lose 3–8% of muscle mass per decade. After 60, this decline accelerates, threatening mobility and independence. But recent research shows that exercise doesn’t just slow the decline—it works at a molecular level to keep muscles healthy.

A study published in PNAS identifies DEAF1, a transcription factor, as a key driver of age-related muscle weakening. According to Tang Hong-Wen, Assistant Professor at Duke-NUS Medical School, Singapore, exercise suppresses DEAF1, restoring the muscle’s ability to repair itself rather than just grow.

“We believe our findings uncover a previously unknown mechanism behind muscle weakening with age. Exercise protects muscle health by directly modulating DEAF1,” said Tang.

Understanding DEAF1, mTORC1 pathways

Researchers found that DEAF1 becomes more active in aging muscle, triggering mTORC1 hyperactivation, which shifts muscle cells’ focus from repair to unchecked growth. This imbalance leads to weakened, fragile muscles. Sebnem Unluisler, genetic engineer at the London Regenerative Institute, explained:

“Aging shifts muscle protein regulation away from repair, and DEAF1 suppresses the cell’s ability to clear damaged proteins, leaving muscle tissue vulnerable.”

How exercise restores muscle balance

Physical activity turns on protective FOXO genes, which act as brakes on DEAF1. When DEAF1 is suppressed, muscle cells regain their ability to recycle damaged components and produce proteins needed for repair. Both resistance training (weights, bodyweight exercises) and aerobic activity (brisk walking, cycling, swimming) activate FOXO pathways, protecting muscles from age-related decline.

“Exercise restores the muscle cell’s ability to fix itself. Resistance exercise provides the strongest stimulus, but a combination of aerobic and strength training is ideal,” said Sebnem Unluisler.

It’s never too late to start

Even in older adults, DEAF1 can be suppressed, and cellular repair mechanisms reactivated. Tang encourages all ages to stay active:

“Muscle aging is not just about losing mass—it’s losing the ability to maintain healthy muscle. Exercise, at any age, can help preserve strength, mobility, and independence.”

Practical steps include brisk walks, cycling, swimming, and light resistance exercises multiple times a week. These activities not only build strength but also activate cellular pathways that repair and maintain muscle tissue, slowing the effects of aging.

Stay informed, stay healthy!

CLICK HERE TO JOIN Medical News Pakistan on WhatsApp for latest stories, expert tips, health updates, and the medical research straight to your phone.