A pregnant woman stretches before she undergoes moderate exercise outside.
If you’re pregnant and just getting started with exercise, a moderate level of activity is your best bet. (For Spectrum Health Beat)

Almost everyone can use a little exercise, including moms-to-be.

But women who are expecting may want to take some extra precautions and know the do’s and don’ts before undertaking a fitness program.

“Especially in pregnancy and prior, exercise activity is really important,” said Caesy Yarling, DO, a primary care sports medicine physician with Spectrum Health. “But individuals differ, so it’s also important to first discuss any exercise activity with their physician or obstetrician.”

Regular exercise can help pregnant women reduce back pain and fight constipation. It can also promote healthy weight and improve aerobic ability.

Because each woman differs, the intensity level of any exercise program will vary.

Moderation is best

When in doubt, a moderate exercise program featuring aerobic and strengthening activities is recommended, Dr. Yarling said. This usually entails about 20 to 30 minutes a day, five days a week—typically under a doctor’s guidance.

With a workout of moderate intensity, you’re typically able to talk during exercise.

Some low- to moderate-intensity activities, meanwhile, include walking, swimming, water workouts and using a stationary bike.

Women who have previously been involved in higher intensity exercises—such as jogging, running and racket sports—can probably continue these activities, at least initially.

“If they start having difficulty doing some of the movements, they should listen to their bodies and look for modifications or reduce the intensity,” Dr. Yarling said.

Ready for change

There may come a point in the pregnancy when a woman has to start changing her exercise routines.

For example, usually after 16-20 weeks of pregnancy women should avoid lying flat on their backs. Their changing anatomy will affect some of the movements they can do.

“I always recommend modifying activities to accommodate a growing belly,” Dr. Yarling said. “There are lots of prenatal classes that women can take. And if they need some medical direction, they can talk to a sports medicine doctor.”

The types of exercises pregnant women can do will also depend on their physical condition. Everyone starts in their own place, she said.

For mothers-to-be who already carry more weight, exercise is recommended because it can help achieve and maintain a healthy weight, Dr. Yarling said.

Watch for warning signs

Certain warning signs will indicate that a woman should discontinue an exercise or workout program.

This includes vaginal bleeding, contractions while exercising, dizziness, headaches and chest pain, Dr. Yarling said.

Watch for swelling in the lower extremities—severe or unilateral (one sided) swelling that would need to be reported to their doctor immediately.

Generally, expectant women should avoid high-intensity exercises because of the risks they carry.

This includes most contact sports, given the danger of falling or being struck in the abdomen.

Pregnant women should also avoid activities that put them at risk of overheating, such as hot yoga and pilates. A stationary bike may be OK, but women should monitor the intensity level—intense stationary biking could be too much for some pregnant women.

Another important tip: Avoid exercising outside when it’s hot and humid. Modify the activity or take it indoors.

It’s critical to stay hydrated and wear the proper clothing, Dr. Yarling said.

Standing for long periods of time can also cause problems, because it changes vascular and blood circulation. This can make pregnant women feel lightheaded or dizzy, resulting in an injury-causing fall.

Also, remember that hormones change during pregnancy.

Hormones relax the ligaments, which can help in a delivery but cause an injury because the joints can be over-extended. There’s a higher risk of injury from relaxing the ligaments.

“Generally, moderate physical activity and exercise in pregnancy—if done under the watchful eye of a physician—can be very beneficial to moms-to-be,” Dr. Yarling said. “It will help both the mother and the baby have a healthy pregnancy and delivery.”