In a new research study it was discovered that exercising not only keeps you fit but is also known to reverse skin aging in people who exercise regularly.

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 aging in these animals. When members of this breed of mice remained sedentary, they rapidly grew wizened, frail, ill, demented, and graying 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. The researchers speculated that this might do the same for our skin.

Researchers at McMaster University in Ontario began to wonder if such alterations were inevitable.So to test that possibility, the scientists first gathered 29 local male and female volunteers ages 20 to 84. About half of the participants were active, performing at least three hours of moderate or vigorous physical activity every week, while the others were resolutely sedentary, exercising for less than an hour per week. Then the researchers asked each volunteer to uncover a buttock.

“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.

But those results shifted noticeably when the researchers further subdivided their samples by exercise habits. They found that after age 40, the men and women who exercised frequently had markedly thinner, healthier stratum corneums and thicker dermis layers in their skin. Their skin was much closer in composition to that of the 20- and 30-year-olds than to that of others of their age, even if they were past age 65.

But now the samples looked quite different, with outer and inner layers that looked very similar to those of 20- to 40-year-olds. “I don’t want to over-hype the results, but, really, it was pretty remarkable to see,” said Dr. Tarnopolsky, himself a middle-aged exerciser. Under a microscope, the volunteers’ skin “looked like that of a much younger person, and all that they had done differently was exercise.”

How exercise changes skin composition is not completely clear, but in a separate portion of the study, the researchers checked for alterations in the levels of certain substances created by working muscles. Called myokines, these substances are known to enter the bloodstream and jump-start changes in cells far from the muscles themselves. In this case, the scientists found greatly augmented levels of a myokine called IL-15 in the skin samples of volunteers after exercise. Their skin samples contained almost 50 percent more IL-15 after they had been exercising than at the start of the study.

Nor is there evidence that exercise reverses wrinkling and other damage from the sun, some of which many of us accumulate during outdoor exercise. Still, Dr. Tarnopolsky said, “it is astonishing to consider all of the intricate ways in which exercise changes our bodies —including the skin ".

Source:NY Times