Public-health efforts on obesity have been misplaced and counterproductive. Fitness - independent of weight - contributes to good health. A fit person who is heavy is at less risk of diabetes, cardiovascular disease and fatal heart attack than an unfit, heavy person, and perhaps even than an unfit person of "normal" weight, according to some studies. "Fitness is more important than fatness," says Mark Tarnopolsky, an expert in exercise at McMaster University's medical school in Hamilton.
Canada spends far too much time obsessing over "fatness" - that is, on trying to slim down the obese (24 per cent of Canadians) and the merely overweight (37 per cent). The effort has been largely futile. What's worse, when people exercise and find that they don't lose weight, they give up. Exercise on its own rarely leads to weight loss.
Later this month, national guidelines on physical activity will be revised downward, a positive step. Adults are currently told they should exercise an hour a day at minimum. It's out of touch with how people live. Thus, few bother to try. The new target will be 150 minutes a week, the World Health Organization standard. It's doable.
But Canada shouldn't stop there. The doable principle ought to be at the heart of public health, and that means turning the focus to exercise and movement, and away from how much individuals weigh. Obesity isn't like smoking. It isn't a habit. It is built in part on habits, but those are woven into society-wide practices (such as reliance on fast food, on desk jobs, on the car) that are difficult to remake. It is also a matter of genetics. It does not yield easily to social engineering.
Exercising in a safe way at any weight is a more limited and therefore achievable goal. For those motivated by vanity, exercise may keep additional pounds at bay, even if it leaves existing adiposity untouched.
But perhaps even the term "exercise" is off-putting. It may be more doable to "move" for 150 minutes a week, or 30 minutes a day, five times a week, than to exercise. Six five-minute periods of movement a day are as effective as three 10-minute bouts or one 30-minute program, Glenn Gaesser, an expert in exercise physiology at Arizona State University, says. Prof. Tarnopolsky stresses the need to work hard enough to be nearly short of breath, or to feel sweaty.
Heavy people who go out to pound the pavement as runners would get joint pain and eventually osteoarthritis, Prof. Tarnopolsky says. But cycling (on a stationary bike, for instance) safely takes the weight off the joints. So does swimming. Walking (not strolling) is fine, too.
Five minutes at a time. It's doable. Let's put fatness on the back burner and give fitness at any weight or body shape more of the public-health spotlight.