Exercise not only appears to keep skin younger, it may also even reverse skin ageing in people who start exercising late in life, according to surprising new research.
As many of us know from woeful experience, our skin changes as the years advance, resulting in wrinkles, crow’s feet and sagging skin. This occurs because of changes within our layers of skin. After about age 40, most of us begin to experience a thickening of our stratum corneum, the final, protective, outer layer of the epidermis, itself the top layer of your skin. The stratum corneum is the portion of the skin that you see and feel. Composed mostly of dead skin cells and some collagen, it gets drier, flakier and denser with age.
At the same time, the layer of skin beneath the epidermis, the dermis, begins to thin. It loses cells and elasticity, giving the skin a more translucent and often saggier appearance.
These changes are independent of any skin damage from the sun. They are solely the result of the passage of time.
But recently, researchers at McMaster University in Ontario began to wonder if such alterations were inevitable. Earlier studies at McMaster involving mice that were bred to age prematurely had shown that a steady regimen of exercise could stave off or even undo the signs of early ageing in these animals. When members of this breed of mice remained sedentary, they rapidly grew wizened, frail, ill, demented, and greying or bald. But if they were given access to running wheels, they maintained healthy brains, hearts, muscles, reproductive organs, and fur far longer than their sedentary labmates. Their fur never even turned gray.
Of course, we humans long ago swapped our fur for naked skin. But if exercise could keep animals’ outer layer from changing with age, it might, the researchers speculated, do the same for our skin.
“We wanted to examine skin that had not been frequently exposed to the sun,” said Dr. Mark Tarnopolsky, a professor of pediatrics and exercise science at McMaster who oversaw the study, which was presented this month at the American Medical Society for Sports Medicine annual meeting in New Orleans.
The scientists biopsied skin samples from volunteers and examined them microscopically. When compared strictly by age, the skin samples overall aligned with what would be expected. Older volunteers generally had thicker outer layers of skin and significantly thinner inner layers.
But those results shifted noticeably when the researchers