Fit or fat? What's it gonna be? We all know the answer to that one.
But what if the question's a little tougher: If you could pick only one, would you choose to be fit but fat? (Yes, those people exist. I can't be the only one out there who's sometimes made the dumb pre-gym-class mistake of sizing up a blocky fitness instructor as a pushover.) Or would you rather be thin but not physically fit?
That's not an idle question. Researchers, it turns out, have been puzzling over the matter for years, anxious to know which to emphasize -- diet or exercise? -- in the quest to stay healthy.
On the surface, at least, two studies that made headlines last week made the answer look like a toss-up. One study, in the Journal of the American Medical Association, suggested that women's physical fitness level was a much better predictor than body weight of the risk of heart disease. (Translation: Fitness rules. Particularly when this study is viewed along with a prior study that found poor fitness in women poses a greater risk of death than it does in men.)
But the other study, also in JAMA, found a woman's body mass index, or BMI -- a common measure of weight relative to height -- was a far better predictor than fitness level of her risk of contracting diabetes. (Translation: Hey, wait a minute. Didn't you just say . . . )
So where does that leave you and me? With two conclusions, the Moving Crew submits:
* Pursuing both goals -- regular exercise plus weight control -- is uncontestably better healthwise than an either/or policy for both men and women.
* But if you have to prioritize and pick just one goal, pick fitness. That's not just because it's more readily attainable -- though it is. It's also because if you pursue it diligently, you have a better chance shot at weight control.
If on the other hand you were to pursue a healthy BMI without exercising, there would be no certain benefit to your fitness.
That's not just the Moving Crew's opinion. There's good evidence.
Brian Sharkey, former president of the American College of Sports Medicine, cites some of it in his tome "Fitness & Health" (Human Kinetics, 1979), now in its fifth edition. When women in two studies used diet, exercise or a combination of both to lose weight, all succeeded. But the women who exercised lost more fat, conserved more lean tissue and maintained their metabolic rate at a level needed to burn calories.
Those who relied on diet alone, by contrast, typically experienced a 10 to 15 percent drop in metabolic rate that made it hard to retain weight lost. Just two weeks of exercise, Sharkey said, restored the metabolic rate to its pre-diet level.
When you engage in moderate exercise (such as walking, jogging or cycling) 30 minutes or more per day at least five days a week, as recommended for women by the Centers for Disease Control and Prevention, you boost your calorie burning not only during those 30 minutes, but for another half hour or more after you stop.
Add weight training a few times a week to maintain or increase lean muscle tissue, and you can rev up the system a bit further, burning perhaps 30 or 40 calories a day more.
Accelerated calorie burning, of course, is not the only reason to exercise. Among some of the other benefits are more strength, flexibility and energy to do the things you like to do, a more positive mental outlook and better overall health.
But you didn't need any fancy medical research to tell you that.
Join us for the Moving Crew online chat Thursday at 11 a.m. at www.washingtonpost.com/wp-dyn/liveonline/health/movingcrew. Our topic this week: Women's Fitness. Can't make the chat? Share your comments with us anytime at firstname.lastname@example.org. Here's to fitting in fitness.
-- Susan Morse