You've heard it your entire life: you must powerwalk, jump rope, and/or perform other forms of strenuous exercise at least three times a week if you want to be healthy.
It's not a problem for me. Until a knee injury sidelined me last year, I eagerly played four to six hours of tennis a week. I just ordered an exercise bike to help strengthen the post-operative knee and suspect that I will use the contraption for years to come (riding a bike is in my Dutch genes, but I now prefer a stationary one since it allows me to watch the Simpsons while pedaling, rather than maneuver out of the way of exhaust-belching cars whizzing by). With any luck, I'll be back on the courts in a few short months.
Anyway, how much stock should we put in the decades-long exhortations that, to stave off death's clammy grip, we must exercise vigorously at least every other day? The benefits of exercising are a mixed bag, say Gina Kolata in the New York Times.
Exercise has long been touted as the panacea for everything that ails you. For better health, simply walk for 20 or 30 minutes a day, boosters say — and you don’t even have to do it all at once. Count a few minutes here and a few there, and just add them up. Or wear a pedometer and keep track of your steps. However you manage it, you will lose weight, get your blood pressure under control and reduce your risk of osteoporosis.
If only it were so simple. While exercise has undeniable benefits, many, if not most, of its powers have been oversold. Sure, it can be fun. It can make you feel energized. And it may lift your mood. But before you turn to a fitness program as the solution to your particular health or weight concern, consider what science has found. ...
[I]t is impossible to know with confidence whether exercise prevents heart disease or whether people who are less likely to get heart disease are also more likely to be exercising.
Scientists have much the same problem evaluating exercise and cancer. The same sort of studies that were done for heart disease find that people who exercised had lower rates of colon and breast cancer. But whether that result is cause or effect is not well established. Exercise is often said to stave off osteoporosis. Yet even weight-bearing activities like walking, running or lifting weights has [sic] not been shown to have that effect. ...
Exercise alone, in the absence of weight loss, has not been shown to reduce blood pressure. Nor does it make much difference in cholesterol levels. Weight loss can lower blood pressure and cholesterol levels, but if you want to lose weight, you have to diet as well as exercise. Exercise alone has not been shown to bring sustained weight loss.Just ask Steven Blair, an exercise researcher at the University of South Carolina. He runs every day and even runs marathons. But, he adds, “I was short, fat and bald when I started running, and I’m still short, fat and bald."
Feel free to add the limitless benefits of exercise to all the other claims that health nannies loved to beat us all over the head with, only to be proven wrong time and again.
Mark Twain said it best:
"the only way to keep your health is to eat what you don't want, drink what you don't like, and do what you'd druther not."
Posted by: Martin Owens | Thursday, January 17, 2008 at 11:52 AM