Pill Impacts Exercise
-- Exercise is supposed to lift your mood, strengthen your bones
and slim you down. But if you're a young woman on birth control
pills, a workout can spell trouble for your bones.
That is the
unexpected finding of research at Purdue University into what
happens to women's bodies when they exercise moderately.
[pill] prevents the exercise from reaching its maximum effectiveness
in protecting bone," said Connie Weaver, professor of foods and
nutrition at Purdue.
is good news too: The correct amount of calcium in your diet will
forestall any bad bone effect from oral contraceptives.
studied 180 women, between 18 and 30, for up to two years. One
group did little exercise, while another group had to lift weights
and engage in cardiovascular exercise for up to four hours a week.
the women were paid for the study, only 55 completed it, Weaver
noted. The results are in a recent issue of the journal Medicine
and Science in Sports and Exercise.
were first surprised to find that many of the women were already
losing bone mass -- 1 percent to 2 percent a year -- from their
hips and spines, even at their young ages. "We don't expect premenopausal
women to be losing bone at all, so it was a big shock," Weaver
But she said,
"The exercising women had better bones than the sedentary women,"
unless the exercisers were on birth control. Then, for reasons
that aren't clear, their bones were in worse shape than those
of the couch potatoes.
birth control is holding estrogen at a low constant level, reducing
the spikes in estrogen that help bone," Weaver said.
intake of calcium kept the bone problems at bay in all the women.
For that reason, young women shouldn't stop going to the gym,
exercising," she urged. "Keep on exercising for your overall health,
but make sure you get enough calcium when you do."
be just one part of the whole dietary picture, said Dr. Anne Zeni
Hoch, an assistant professor of physical medicine and rehabilitation
at the Medical College of Wisconsin and an expert on how exercise
affects the female body.
have shown that diet in general, not just calcium, affects bone
mass in female athletes, she said. The Purdue research may not
have taken that fully into account, she added.
"need to be consuming enough calcium, but they also need to consume
enough calories," she said.
of what causes bone loss, the results could be catastrophic, she
said. Losing minerals inside bone could lead to a higher risk
a young female athlete in your teens or 20s, pay special attention
to your diet, especially your calcium intake. You don't need to
eat more calcium than other women, but it's more important that
you get enough.
To learn how
much calcium you need, check this National Osteoporosis Foundation
about osteoporosis, from a young women's point of view, at the
National Women's Health Information Center.
Reference Source 101