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Safe Fitness Tips for Expectant Moms

By Kristi Molinaro | September 21, 2012 8:39am

NEW YORK CITY — It happens fairly regularly to me: A few minutes before I am about to start teaching my workout class, a woman walks up to me, generally someone who has been taking the class often, with a pensive look on her face.

She takes a deep breath and says, “Kristi, can you help me? I am a couple months pregnant, and I really need to work out, but I am not sure if this workout is too hard. Can I keep coming?”

Luckily, for her and most women, the resounding answer is 'Yes!' The benefits of regular physical activity during pregnancy definitely outweigh the risks. There are, however, some guidelines to follow and some myths to debunk:

1. Can I exercise throughout my pregnancy?

It is always a good idea to get clearance from your OB before you start or continue your exercise program. Suzanne LaJoie, OB/GYN at Downtown Women’s Group in SoHo and my personal doctor, said that very few women will not get the OK from their doctor. The American Council of Gynecologist recommends that pregnant women maintain an active lifestyle, but women at risk for preterm labor should avoid exercise.

2. How intense can the activity be?

This depends mostly on how fit you were before you got pregnant. I have had plenty of women take my interval class up to the final week of their pregnancy and I, myself, taught class all the way through. There are some modifications that should be made:

On a scale from 1-10, with 10 being as hard as you can go, stay around an 8.

Stick to workouts your body is already familiar with. A very challenging workout may be safe for someone familiar with the tricky choreography, but dangerous for someone who is not especially as the pregnancy progresses. Additional weight on the joints coupled with a hormone called relaxin, which loosens the joints in preparation of childbirth, can be a recipe for disaster. A simple missed landing that you might have recovered from pre-pregnancy could mean an actual fall during pregnancy.

3. Is my heart rate an OK way to monitor my exertion while pregnant?

Heart rate is not a good indicator of output and, therefore, not a great way to monitor your intensity. I often see newly pregnant, super-fit women standing in the back of my classroom marching in place and staring at their heart-rate monitors trying to get their rate below 140 beats per minute. It drives me crazy, because the American Congress of Obstetricians and Gynecologists took the heart-rate limitation out of their guidelines back in 1996, and plenty of doctors are still telling their patients this outdated information.

4. Can I do sit-ups?

Avoid lying on your back after the first trimester. I personally feel that it is time to take a break from traditional abdominal exercises — you will be making up for those lost crunches in about 9 months! Planks are still great exercises that should be done throughout your pregnancy, because they strengthen the deep core, which can be a big help during labor, and toward getting your pre-baby abdominals back.

5. Can I do hot yoga?

Skip the Bikram yoga class. For many years, it was thought that women should keep the intensity of exercise during pregnancy very low because high core body temperature is not healthy for a growing baby. We now know this is not true; the heat a pregnant woman creates is easily moderated by her own body. In fact, some studies show that women control their core temperature more efficiently during pregnancy than they do normally. The only heat she has to be concerned with is external heat from very hot rooms or saunas. So, if your spin teacher likes to keep the AC and the fans off, it might be time to find a new instructor — at least for the next few months.

6. What if I don’t feel well enough to work out? How important is it?

Many women feel horrible during their first trimester, and some for longer. But becoming active can help with some of these symptoms, and the benefits of exercise during pregnancy are huge. Regular workouts lower the risk of gestational diabetes, help with mood swings prevalent in pregnancy, improve body image, help prevent lower back pain and can possibly increase stamina during labor. Women who continue their exercise program throughout their pregnancy are also much more likely to return to their pre-pregnancy weight — and much sooner.

7. What if I am having trouble getting pregnant? Should I stop working out?

Maybe. Daily intense workouts coupled with low body weight can make it very difficult for many women to conceive. If you have been trying to conceive for six months with no luck, it is time to visit your OB, especially if you are over 35.

8. Can I work out during my fertility treatments?

This gets a bit trickier. Generally, when a woman is seeking help conceiving, she is already in a delicate situation. Many fertility specialists will recommend no exercise at all after embryo transfer. Dr. LaJoie explains why most specialists take this "better safe than sorry" approach with IVF treatments: “The doctor will hyperstimulate the ovaries to enlarge them and to form follicles. When this occurs the ovary can be painful, and in rare circumstances twist on itself, which is called torsion.” The bottom line is that if you have gotten to the point where you are ready to commit to IVF treatments, you want to give yourself the best possible chance of implantation and a healthy pregnancy. Taking two to three weeks off from your favorite exercise class is probably a good idea. Take a yoga class, go for a swim or a brisk walk.

Now, happy baby-making!