Pregnancy No Excuse for Inactivity
Feb. 16, 2000 (Atlanta) -- There are physical and psychological benefits to
initiating exercise during pregnancy, according to a report in the January
issue of Medicine & Science in Sports & Exercise. Experts say
supervised exercise significantly increases aerobic fitness and emotional
well-being in previously inactive women, without adverse effects on pregnancy
After doctors had characterized the pregnancies as low-risk, researchers
randomly assigned 15 inactive women to one of two study groups. Physical
measurements were obtained, and body image was evaluated using a standard
scale. Additionally, heart rate and blood pressure were monitored before,
during, and after a baseline exercise session.
The training program consisted of three one-hour sessions per week for 15
weeks. For the first two weeks, the sessions combined rowing, stationary
cycling, and walk-jogging, with a maximum heart rate of 130. Afterward,
rhythmic calisthenics, step aerobics, and brisk outdoor walks were introduced,
with a maximum heart rate of 156.
After 15 weeks, the exercise group showed significant increases in aerobic
fitness and perceived stamina, strength, and energy. But there were no
differences in the percentage of deliveries by cesarean section or infant
status at birth. For these reasons, the authors say that inactive women with
low-risk pregnancies should participate in supervised exercise.
"Many experts urge caution about exercise during pregnancy for women
who've been sedentary," says study co-author Arlette Perry, PhD, an
associate professor of physiology at the University of Miami. "And others
advise against it, because there are no specific guidelines."
"Recent studies have shown that active women tolerate labor better, have
fewer episodes of fetal distress, require less medical intervention, and
deliver leaner babies," says Perry. "Now, we've demonstrated the safety
and effectiveness of supervised exercise during pregnancy in previously
inactive women." Doctors say that common sense and safety should moderate
"Early in pregnancy, physically fit women can usually maintain their
workouts," says Michael Lindsay, MD, division director of maternal-fetal
medicine and associate professor of obstetrics and gynecology at Emory
University in Atlanta, who reviewed the study for WebMD. "But later in
pregnancy, aerobics and jogging increase the risk of falls. Throughout
pregnancy, the maximum heart rate should never exceed the resting pulse
multiplied by two."
"We introduced exercise during the second trimester -- with medical
clearance -- to reduce the risk of complications," says Perry. "That
means the findings may not be applicable to the general population. Clearly,
the data must be replicated with a larger and more representative sample."
Perry tells WebMD that she looks forward to conducting more research in this
- New research shows that supervised exercise in previously inactive pregnant
women improves fitness and emotional well-being, without any adverse effects on
- Some in the medical community advise against exercise during pregnancy for
inactive women, but these findings seem to counter that advice.
- Throughout pregnancy, a woman's maximum heart rate should never exceed her
resting heart rate multiplied by two.