Parenting: Running a marathon pregnant. Really?!

October 21, 2011

I've run nearly a dozen marathons (including the Chicago Marathon four times,) so I know just how taxing covering 26.2 miles can be on your body, even when NOT pregnant. At the same time, I exercised through both of my pregnancies, even running up to a few days before giving birth to my son. But, I likely didn't cover 26.2 miles in a week at the end of my pregnancy, never mind in a day. That being said, Miller gave birth to a healthy girl and said her doctor cleared her to run/walk the marathon, which she did in six and a half hours instead of her usual three and half.

So, is running a marathon while pregnant safe?

Just a decade ago, vigorous exercise during pregnancy was seen as dangerous to the baby. Pregnant women were told to keep their heart rates below 140 beats per minute. Recently, those guidelines were dropped and doctor's groups are increasingly pushing pregnant women to get moving. A 2009 study in the Journal of the American Academy of Orthopaedic Surgeons found exercise during pregnancy can improve the mother's health and positively impact pregnancy-related symptoms. It also cited a 2005 article in the Journal Medicine & Science about a national survey of 144,000 non-pregnant women and 6,500 pregnant women done between 1994 and 2000 that found only one in six pregnant women got the recommended amount of physical activity.

The American College of Obstetricians and Gynecologists (ACOG) advises at least 30 minutes of exercise on most, if not all, days of the week. Among other benefits, physical activity can reduce backaches and constipation, improve mood, energy and sleep, and help women endure and recover better from labor. At the same time, ACOG warns that there are potential dangers involved in exercising too much during pregnancy. Low birth weight (defined as less than 5 1/2 pounds) is a concern especially if you are a pregnant woman running 60 miles a week, which is likely if training for a marathon. If you run high mileage you may end up struggling to get enough nutrition for you and your baby. If you plan to run while you are pregnant, doctors warn that you need to be vigilant about your calorie intake and really focus on balancing out running with eating. The Mayo Clinic recommends that any pregnant exercisers should also make sure to drink enough water, avoid overheating, and stop if they feel any concerning symptoms.

And pregnancy certainly isn't the time to start a running routine, according to Julie Tupler, a registered nurse, certified personal trainer, and founder of Maternal Fitness, a fitness program for pregnant women and new moms. Pregnancy's also not the time to start training for a marathon, a triathlon, or any other race, cautions Tupler. "The first trimester is when the baby's major organs are forming, and overheating is a real issue. If a woman's core temperature gets too high, it could cause problems with the baby, so why risk it", she says. I'm the first to admit that runners are often "type A" personalities who hate to deviate from a training plan. Miller reportedly signed up for the marathon before she knew she was pregnant and didn't want to forfeit the registration fee. But, if I were in her situation, instead of racing, I would have watched the race from the sidelines, cheered on the competitors, and prepared for the real marathon of being a mom.

Happy parenting! Cecily

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