Three days before Nancy Karabaic's baby was born -- when most moms-to-be are finding it tough enough just walking a couple of blocks -- Karabaic took a 3.5-mile run, because it felt good, she says.
"It was really important to me to stay fit and strong throughout my pregnancy," says the 39-year-old personal trainer from Wheaton, Md. "There's so little you can control when you're pregnant that at least you can feel like you're doing your best to stay healthy. I felt it would make my baby healthier, too."
So after talking over safe and reasonable guidelines with her midwife, Karabaic continued to swim, bike, run and lift weights -- albeit at a lesser intensity than she was used to -- throughout the nine months of her pregnancy.
To Karabaic, who delivered a healthy 7-pound, 6-ounce boy last January, the benefits were clear.
"My health stayed really good, I felt better emotionally, and I still felt like I looked good -- I had that healthy glow you get when you're exercising and you're pregnant." She's also convinced her labor, delivery and recovery were smoother because she was in such good shape.
The average pregnant woman won't be taking a three-mile jaunt, however, nor should she. Still, recent studies on pregnant women like Karabaic are shattering a lot of myths about the potential dangers of moderate-to-strenuous exercise during pregnancy.
That's good news for women who have been fairly active before conceiving. It's also reassuring news to those, even novices, who are concerned that exercise might hurt them or their baby.
"Exercise is not a process that needs be eschewed or prevented during pregnancy," says Dr. John Botti, director of maternal-fetal medicine at Penn State Geisinger Health System, who studied the effects of exercise on moderately conditioned pregnant women. "Reasonably performed exercise doesn't appear to cause harm, and may, in fact, have benefits."
The key is finding a reasonable level, and that depends largely on the shape you were in before, the activities your body was comfortable with, and your health during pregnancy. Always check with your doctor or midwife first, but here's food for thought for the novice and the enthusiast, as well as some basic dos and don'ts.
The Novice: Walking and Water Spell R-E-L-I-E-F
"Only 20% to 30% of the population exercises on a regular basis, so the typical pregnant woman hasn't exercised prior to pregnancy," says Bonnie Berk, creator of MOTHERWELL, a pre- and postnatal fitness program offered throughout the United States and abroad.
Still, it's not too late for pregnant women who haven't been consistent exercisers to start now. Although hard data on the value of prenatal exercise isn't as well-documented for unfit women as for fit ones, experts like Berk have seen firsthand the difference that exercise can make, even for couch potatoes.
For one thing, by doing exercises that strengthen the muscles supporting the uterus, women stand to experience fewer complications like backaches, ankle swelling and fatigue during pregnancy, and their bodies will be better prepared for the rigors of childbirth, too.
Exercise also typically reduces stress and enhances body image, so pregnant women who are working on their fitness level often feel better about themselves. Such was the case for Dena Higgins, a nurse from Carlisle, Pa., who took MOTHERWELL water aerobics classes twice a week before her son, Joshua, was born last December.
"It was so nice to go exercise at the end of the day, get away from work for a while and just concentrate on myself and the baby," recalls Higgins. "It just made me feel so much better." In fact, Higgins admits while she wasn't successful at fitting in a regular exercise routine before pregnancy, she's hooked now and is already taking a mom-infant class.
Of course, that doesn't mean it's time to suddenly get hard-core, either.
Incorporating some moderate aerobic activity, such as walking or swimming, and some flexibility and strengthening work, like yoga, is all any pregnant woman needs, says Berk. About 20 to 30 minutes of brisk walking three to four times a week is plenty, four to five times if you're trying to minimize weight gain.
Overexertion may cause a dangerous reduction in blood flow to the fetus, so the American College of Obstetricians and Gynecologists recommends mild-to-moderate exercise and stopping when fatigued. (It recommends mild-to-moderate exercise at least three times per week.) Rather than targeting a specific heart rate, many experts say it's more important for women to pay attention to "perceived exertion," which is basically how hard they're breathing and feel they're working.
"You don't want to push yourself beyond your individual tolerance level, and the best measure of that is your own breath," says Berk. "You should never be breathing so hard that you can't talk." You may also feel differently from one day to the next, "so you really need to listen to your body and exercise according to how you feel that day," says Berk.
To help make sure your baby's handling the extra effort, Berk suggests taking some time each day to count your baby's kicks. Fetuses usually kick at least five times an hour, but since babies have 20-minute sleep cycles, if the baby doesn't kick five times, try counting again for a second hour. If you have concerns, check with your health-care provider.
Don't panic if the kicks get more active right after you've exercised, either. Your baby is just responding to a rush of oxygen and glucose that's been diverted temporarily during exercise. It's nothing to worry about as long as you're not overdoing it, she says.
Besides brisk walking, swimming and water aerobics are ideal for pregnancy. Not only does water make you feel 90% lighter, but it helps rid your body of excess fluid and minimizes edema. Water sports also carry little chance of physical injury, and water resistance helps tone and strengthen muscles.
Yoga can be particularly beneficial during pregnancy because the deep breathing relaxes and centers you, helps prepare you for the focused breathing you'll need during labor, and tones abdominal muscles. It's a good all-around muscle strengthener, too. In fact, Berk does yoga every day, has decreased the amount of weight training she does, and still maintains her strength.
Higgins says she liked going to an exercise class designed specifically for pregnant women because it gave her a chance to commiserate with others in the same boat. Also, having a trained instructor on hand to make sure you're performing an exercise correctly can help reduce the chances of injury.
If you're going solo, a number of books and videos provide detailed programs, including "Maternal Fitness," by Julie Tupler; "Water Fitness During Your Pregnancy," by Jane Katz; "Essential Exercises for the Childbearing Year: A Guide to Health and Comfort Before and After Your Baby Is Born," by Elizabeth Noble and "Yoga for Pregnancy," by Sandra Jordan. MOTHERWELL also has an exercise video, which can be previewed by checking the organization's Web site.
The Conditioned Athlete: Keep It Up, but Down a Notch
Until recently, athletic women like Karabaic were cautioned by most doctors to curtail intense physical activity, particularly exercise that involved jumping, bouncing or impact, like running or aerobics, and advised to switch to walking, swimming and stretching because there wasn't enough evidence to show that moderate-to-intense activity was safe.
But research by experts like Dr. James Clapp III, author of "Exercising Through Your Pregnancy," is debunking the prevailing conservative stance. He tracked the effects of frequent (five or more times per week), prolonged (30- to 90-minute) bouts of high-intensity (65% to 90% of maximum capacity), weight-bearing exercise on competitive runners and aerobic dance instructors.
Dr. Clapp found that these pregnant athletes' bodies were not only conditioned to handle the physical changes that occur from more strenuous workouts -- such as increased heart rates, higher body temperatures, stress on muscles and ligaments, and reduced levels of oxygen and glucose -- but that they had easier, healthier pregnancies when they continued these activities.
Women who continued regular weight-bearing exercise above 50% of their prepregnancy levels tended to have fewer physical discomforts, gained about 8 pounds less than those who stopped exercising, and did not sustain more injuries or complications such as membrane ruptures. They also had easier, shorter and less complicated labors with less medical intervention, like pain relief, pitocin and episiotomies, and recovered faster.
Likewise, the babies weren't adversely affected. They didn't experience oxygen deficiency or stress during exercise, even though their heart rates temporarily increased. Nor did they show a higher risk of prematurity or low birth weight, although they were born a few days earlier, were about 14 ounces lighter and had 5% less body fat -- which Dr. Clapp says could be beneficial to mothers and their babies.
Dr. Botti says that women who keep running or doing moderate-to-strenuous exercise will still have to modify the intensity of their workouts, especially as their pregnancies progress. If you lift weights, switch to lighter ones and increase the reps. You may even have to switch to a lower impact activity, for instance switching from running to cycling or swimming.
The key is your own comfort level. Even pros like Mary Decker Slaney, who holds five U.S. track records, slowed down in her seventh month after experiencing abdominal pains precipitated by running.
"Women can run, but most women find they get too uncomfortable between 20 and 32 weeks," Dr. Botti says. "Your body's probably going to tell you when to start slowing down, and when it does, listen to it."
Karabaic, who usually ran sprints with friends to increase her speed and took one longer, 12-mile run once a week before getting pregnant, stopped doing both. And instead of her usual hour-long workout, she'd go only 45 minutes and never exceeded five miles.
"I radically changed my program, but I still swam, biked, ran and lifted weights," she says. "I just decreased the intensity and time, and I based my workouts on how I felt that day."
Gauging safe levels of exercise by a specific heart rate is even less useful for conditioned women than for novices, since the better shape women are in, the higher intensities they can achieve at lower heart rates.
Experts advise not to push through pain or exhaustion, and to first map out a realistic program with your doctor, and even to seek additional advice, if necessary, from an exercise physiologist familiar with pregnancy -- ideally before you even conceive.
"That way, it allows women time to find out if their health provider is up-to-date (about exercise) and if they're philosophically in tune with them," Botti says. "If they're not happy with the way this person looks at the whole process, they have a chance to get a second opinion."
Some Safe-Exercise Guidelines
Here are some guidelines to help keep your exercise routine safe for you and your baby:
- Any woman who wants to exercise during pregnancy should get their doctor's OK first. Certain medical conditions -- such as preterm rupture of membranes, pregnancy-induced hypertension, preterm labor, persistent second- or third-trimester bleeding, poor fetal growth, incompetent cervix or multiple-birth pregnancy -- may require modifying or avoiding exercise.
- Drink plenty of water before, during and after exercising, particularly in very hot or humid weather. That goes for swimming, too, even though you may not feel dehydrated. An increase in core body temperatures in early pregnancy can cause fetal defects, and dehydration in late pregnancy is associated with premature labor.
- Always include a warm-up and cool-down when putting muscles to work. Gentle stretches will prevent strains, joint injuries and muscle cramps.
- Dress in comfortable clothes that wick sweat and keep you cool. Shoes for running, jogging and walking should have good cushioning under the heel to avoid injuries to the foot or Achilles tendon. Bras should provide good support.
- Don't overflex or overextend the knee joints, as with deep-knee bends, unless your body is well-conditioned for these motions. Knee joints are more prone to injury because of the pregnancy hormone relaxin, which softens ligaments and tendons.
- Stop exercising immediately if you experience symptoms such as chest pains, vaginal bleeding or uterine contractions, or if your membranes rupture.
- Remember to eat a balanced diet, preferably five or six small meals or snacks per day, to replace the calories and glucose used by your working muscles during exercise. Metabolism speeds up during pregnancy anyway.
- Avoid exercises on your back after the first trimester or whenever you feel dizzy, lightheaded or nauseated. The weight of your uterus puts pressure on the vein responsible for returning blood from the lower body to the heart.
- These sports are generally not recommended during pregnancy: contact sports, such as football and basketball; adventure sports, such as water skiing and scuba diving; and sports that carry a high risk of trauma, such as horseback riding and downhill skiing.