June 5, 2006

Ill effects of inactivity reversible with exercise

By Charnicia E. Huggins

NEW YORK (Reuters Health) - Couch potatoes can lower their
risk of developing heart disease, diabetes and other health
conditions, if they start spending as much time exercising as
they previously spent being inactive, new study findings

In the study, men and women whose health and fitness
deteriorated when they volunteered to be physically inactive
for six months, had a complete reversal of most of the
subsequent deterioration in health measures when they increased
their activity level during the next six months.

"Inactivity is worse than we thought," study co-author
Jennifer L. Robbins, an exercise physiologist at Duke
University in Durham, North Carolina, told Reuters Health. Yet,
she said, "a little bit of activity can make a big difference."

Robbins presented her team's findings during last week's
annual meeting of the American College of Sports Medicine, held
in Denver, Colorado.

"Although exercise is known to enhance health and wellness,
the extent to which one can reverse the debilitating effects of
physical inactivity is unknown," Robbins and her associates
note in materials provided at the meeting.

To look into that issue, they studied mildly overweight but
otherwise healthy individuals who had been assigned to a
comparison group of a previous exercise study, in which they
were instructed to not make any changes in their diet or
exercise level -- i.e. to continue their normal pattern of
inactivity -- for a six-month period. These participants
afterwards elected to follow the study's exercise program for
an additional six months.

During their period of inactivity, the men and women
experienced deterioration in 12 of the 17 variables studied,
including their waist size, how quickly they became exhausted
while using a treadmill, and their visceral fat, or the amount
of fat surrounding their internal organs -- a known predictor
of cardiovascular disease.

After six months of exercise, however, the 33 study
participants decreased their waist size, lost weight, exercised
longer before becoming exhausted on a treadmill, lowered their
cholesterol and otherwise improved in 13 of the 17 variables
studied, according to Robbins and her team.

The exercise returned these variables to "normal" -- i.e.
to the levels measured before the initial study began -- or
even led to improvements beyond those initial levels.

"It's promising to know with a similar period of activity,
health parameters can be reversed," Robbins said.

What's more, study participants who fared the worst during
the sedentary period also experienced the greatest improvement
during the exercise program, the researchers note.

This is good news for men and women who recently gained
weight, according to Robbins. "They may indeed be the ones who
have the most benefit" from increasing their level of physical
activity, she said.

The study findings indicate that "it only takes a small
amount of activity to make a difference and to keep
cardiovascular risk factors at a manageable level," Robbins

"Something's better than nothing and more is better than
less, generally," she added.

The research was funded by a grant from the National
Institutes of Health.