Fit Or Fat?
Fit Beats Thin, in a Heartbeat
By Susan Morse -
The WashingtonPost.com
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:
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.
-- Susan Morse
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