The benefits of prenatal exercise are undisputed — for both mom and baby. In fact, many experts say that being inactive is the real risk, leading to high blood pressure, excessive aches and pains, and a high risk for gestational diabetes. Even just moderate activity (like brisk walking) will keep your heart rate up, get your blood circulating, and keep your body in shape for labor.
But there are a lot of myths circulating about prenatal exercise, scaring women off from being active. After the jump, I tackle each myth, debunking it with a mix of research and personal experience …
1. If you weren’t active before pregnancy, you can’t be active now 1 of 10
It's common belief that if you did (blank) before pregnancy, you can (blank) during your pregnancy. While helpful to those who've always been active, it can be confusing to those women who don't know where to get started. What if I used to be a runner, and I haven't laced up in a year? What if I wasn't too active — how much is safe now?
According to Raul Artal, MD, lead author of the American College of Obstetricians and Gynecologists' (ACOG) guidelines on prenatal exercise, "nowhere in the medical literature does it say that moderate exercise such as walking is unsafe, even for previously sedentary women." For normal, healthy pregnancies, Artal recommends walking 30 to 60 minutes a day, broken up however you'd like. The ACOG recommends that previously inactive women should start slowly — beginning with as little as 5 minutes of exercise a day and adding 5 minutes each week until they can stay active for 30 minutes a day.
2. The most important areas to focus on are your pelvic floor, hips, and back 2 of 10
I'm not sure where I read this during my pregnancy, but I focused all of my prenatal strength training on hip flexor and lower-back exercises — thinking it would strengthen the area needed for labor. But then I actually went through labor, and little did I know that it actually works every muscle in your body — even muscles you didn't know you had. (Not to mention you'll spend the next year carrying a heavy car seat/infant/diaper bag.)
Speaking from personal experience, I urge you to strengthen your arms, legs, and core as well. As long as your pregnancy isn't considered high-risk, doing some strength training is completely safe. A recent study conducted by the University of Georgia followed a group of pregnant women, between weeks 21 and 25, for 12 weeks as they weight-trained (with supervision) two days per week. No one was injured. However, it's important to note that you should stop lifting weights at the first sign of dizziness. Overexertion is not healthy for anyone!
3. Ab exercises are out of the question 3 of 10
In an interview with Fit Pregnancy, prenatal fitness trainer Sara Haley said that doing crunches on your back is a no-no because "your growing uterus can compress the vena cava, the major vessel that returns blood to your heart, potentially reducing blood flow and making you feel dizzy and nauseated." But, she reassures, there are plenty of ways to work out your core by standing, kneeling, or using a stability ball. In fact, Haley performed the plank move until the day she gave birth (which she was very thankful for during those last two hours of labor). Read more of Haley's advice.
4. Yoga is dangerous 4 of 10
While there are certain poses that aren't possible during pregnancy, there are specific yoga classes just for pregnant women. The relaxation and meditation techniques in yoga are especially beneficial during pregnancy, so even if your local yoga studio doesn't offer prenatal classes, most yoga instructors will modify a gentle yoga class for you. I've personally gotten so much more out of a yoga class than an at-home DVD — especially because the instructor can ensure your safety.
5. Exercising can cause preterm labor 5 of 10
Though there are a lot of theories that claim exercising can cause preterm labor, there's actually no evidence to support these claims. If you don't have a history of preterm labor and are experiencing a low-risk, healthy pregnancy, exercising in your third trimester is perfectly safe. In fact, prenatal exercise actually helps prep your body for labor and delivery by increasing your stamina and muscle strength.
With that said, always listen to your body. It's normal to be more tired during the last trimester, so take it easy and just do what you can, even if it's a 10-minute walk.
6. Exercising can cause miscarriage 6 of 10
A Danish study of 92,000 women showed no increase in miscarriage from exercise performed after 18 weeks. Before 18 weeks, an increase in miscarriage was found only in women who intensely worked out more than 7 hours per week with high-impact activities. As long as your healthcare provider approves your exercise plans, you can rest assured that you'll actually be doing your body a favor rather than putting it at risk; prenatal exercise can actually reduce some symptoms of pregnancy, such as back pain and other discomforts. So while experts still can't say for sure, it's best to stick to low-impact activities in the first 18 weeks, stay hydrated, and avoid excessive huffing and puffing. It's also a good idea to avoid exercising in the heat so that your core body temperature isn't raised too high.
Photo: Flickr/Denis Todorut
7. Running can damage your fetus 7 of 10
Of course you won't be able to maintain your old pre-pregnancy routine, but if you were a runner before getting pregnant, you can still run during your pregnancy. In an interview with Fit Pregnancy, Raul Artal — author of the ACOG's guidelines on prenatal exercise — said there's no way you can "shake your baby loose." He explained that the amniotic fluid keeps your baby plenty safe. "As long as there are no changes in your joints and ligaments, you can continue running," he said.
BabyCenter has a great list of precautions to take during each trimester, such as running on a track to help you stay balanced and making sure you stay hydrated. You should also stop running if you experience any physical discomfort, vaginal bleeding or leaking, and difficulty breathing.
Photo: Flickr/lululemon athletica
8. Don’t work out more than 3 times a week 8 of 10
According to Lisa Druxman, a pre- and postnatal fitness expert and founder of Stroller Strides, "Following a doctor's approval, it's recommended that pregnant women engage in 30 minutes or more of moderate exercise daily, five or more times a week." (This includes everything from walking down the road to climbing stairs.) The ACOG agrees, recommending exercising and being active "at least 30 minutes on most, if not all, days of the week" to help physical ailments (constipation, backaches, swelling, etc.) and medical conditions (like gestational diabetes), and to help cope with labor and recovery. The ACOG also cites improved mood, energy, and sleeping as reasons to exercise.
9. Your heart rate shouldn’t go over 140 beats per minute 9 of 10
Although this used to be a common recommendation from the ACOG and OBGYNs, women's heart rates vary too widely to stick to this rule. The ACOG now recommends that women use the "Borg Scale" (or the talk test) to determine physical exertion: during moderate activity, you should be able to talk (but not sing) through an activity. Learn more from the CDC guidelines on measuring physical activity intensity.
10. Pregnant women should only do low-impact activities 10 of 10
Yes, pregnancy causes the hormone relaxin to loosen your ligaments to prepare for labor, but you don't need to limit yourself to water aerobics and the elliptical machine from the get-go. Of course there will probably come a time when jogging will feel uncomfortable, but according to fitness instructor Nicole Nichols for BabyFit.com, you can easily modify most pre-pregnancy fitness routines throughout your pregnancy — even spin classes and Pilates — with advice from your instructor. Your body will also tell you its limits, so just pay attention to how you're feeling.
There are some exercises, however, that are off limits. The ACOG recommends avoiding high-risk activities, such as gymnastics, water skiing, and horseback riding, and contact sports, such as hockey, basketball, and soccer. They also recommend avoiding scuba diving because of decompression sickness, and downhill skiing because it shifts your center of gravity and puts you at risk of altitude sickness. Photo: Flickr/University of Salford
Bottom line: Talk to your doctor, stay hydrated, and always listen to your body. But above all else — start moving!