For decades, most medical experts agreed that physical exercise was beneficial to our bodies. Aerobic exercise especially was known to promote increased cardiovascular health, and resistance exercise was effective in building up your muscles. Yet, medical science was unable to state categorically that exercise made any significant contribution to postponing the physical ravages of aging. Recent studies have removed this uncertainty and show that exercise not only delays the aging process but can also reverse it.
The body changes with age in all sorts of ways. Some are obvious, like hair going grey or skin becoming wrinkled. Others are less obvious but much more important. One important and unwelcome change is what’s called sarcopenia – the age-related progressive loss of muscle fiber. It usually starts in our thirties and manifests itself as a loss of muscle mass and strength, decreased aerobic capacity, and less energy. It accelerates in our late sixties. Up until recently, medical science believed that very little could be done about it. New research findings have dramatically changed this thinking. We now know that individuals of all ages can do quite a lot to delay the onset of sarcopenia and slow or even reverse its course. The secret to combating this muscle aging process lies in exercise and diet. In the case of diet, most people put on weight as they age mainly because they eat more food than their less active bodies need. So the appropriate diet’s first aim is to match intake with requirement and, second, to include food that assists muscle tissue development. In the case of exercise, the aim is straightforward, yet far-reaching in its consequences: to build up muscle and slow down the aging process at a cellular level.
Resistance exercises are known to delay the onset of muscle fiber loss and to help build up new muscle tissue, but they achieve much more than that. At a cellular level, the beneficial effects are more significant and only recently understood. Throughout our lives, our cells are continually dividing. With each division, a tiny piece at the end of the cell’s DNA called a telomere is lost. The precise function of telomeres was unknown until three scientists recently solved the puzzle. They were awarded a Nobel Prize in 2009 for their work. The three scientists are Elizabeth Blackburn of the University of California, San Francisco; Carol Greider of the John Hopkins University School of Medicine, Baltimore; and Jack Szostak of the Harvard Medical School, Boston. Their work showed that telomeres are vital in protecting the cell’s DNA. If they did not exist, each cell division would result in important parts of the DNA being snipped off, resulting in very rapid cell death. But the telomeres themselves don’t last indefinitely. Over the years, as cell division continues, they become progressively shorter until they are eventually too short to protect the cell. The result is cell malfunction or cell death.
The length of our telomeres is, therefore, a reasonable indicator of our biological age: younger people have longer cell telomeres than older people, but there are significant exceptions. Another important recent study showed that telomeres in older people who exercised regularly were significantly longer than those of older people who didn’t exercise regularly. Even more striking was the discovery that the telomeres of middle-aged people who took regular exercise were only marginally shorter than those of people half their age who didn’t exercise regularly. This was further confirmation that exercise helps extend the lifespan of the very building blocks of our bodies: our cells.
This cumulative good news means that we can significantly slow the aging process by exercising regularly and by matching the intake of specific nutritional food to our bodies’ needs. There’s just one warning that most people will be happy to heed: don’t overdo the amount of exercise you undertake. A study quoted recently in the New York Times showed that those who exercise to a degree that most people might regard as excessive can damage their hearts. Among those studied were middle age athletes who had each run at least 100 marathons. This, perhaps quirky finding highlights, that with exercise, as with most human activities, one can have too much of a good thing. So, unless you plan to run a marathon every few weeks, you can expect your exercise regime to significantly improve your health and delay the process of aging.