Lower-intensity exercise may melt more pounds
By Amy Norton
A brisk walk through the park might be better than a fast run when it comes
to shedding pounds, a small study suggests.
Researchers found that among 14 women who embarked on a three-month
exercise regimen, those who worked out at a moderate pace lost more
weight than those who exercised more intensively.
But it's not time for runners to start slowing down, according to the study
authors. For one, women in the higher-intensity exercise group did retain
more muscle mass than those who worked out more moderately.
More importantly, though, there is no such thing as one "magic exercise,"
said lead study author Dr. Vassilis Mougios of Aristotle University of
Thessaloniki in Greece.
To get the greatest health and fitness benefits, he told Reuters Health,
people should strive for a mix of moderate and vigorous cardiovascular
exercise, as well as strength training.
Mougios and his colleagues report their findings in the International Journal
of Sports Medicine.
Losing weight basically boils down to burning more calories than you take
in. But it hasn't been clear whether the intensity of a regular workout makes
a difference in body composition - that is, the proportions of fat and lean
tissue.
To study the question, Mougios and his colleagues randomly assigned 14
normal-weight and overweight women to one of two groups: one that
exercised on a treadmill at a moderate pace, four times a week; and one
that worked out at a more vigorous clip, also four times per week.
The researchers set the duration of the workouts so that women in both
groups would burn 370 calories each time.
After three months, exercisers in both groups were slimmer, but the
lower-intensity group lost more weight -- about 7 pounds, on average,
compared with 4 pounds in the high-intensity group.
Fat-free mass decreased slightly (less than half a pound) in the
low-intensity exercisers and increased slightly (about 1 pound) in the
high-intensity group.
It's possible, according to Mougios, that women in the high-intensity group
shed fewer pounds because they ended up eating more, or were so
drained by their regimen that they relaxed more in their leisure time.
In turn, the women may have held on to more muscle simply because they
lost less weight. On the other hand, the researchers note, high-intensity
exercise may actually spur some growth in muscle fibers.
The bottom line, according to Mougios, is that people should stay active
with various forms of exercise. But for those who want to know whether
they're working hard or moderately, he said a heart rate monitor or some
simple pulse checks during the workout will provide that information.
SOURCE: International Journal of Sports Medicine, March 2006.