In 1985 the American Congress of Obstetricians and Gynecologists (ACOG) released its first-ever guidelines on exercising during pregnancy. It cautioned expecting women to limit their heart rate to 140 beats per minute (BPM). That guideline, revised less than a decade later, remains stuck in the minds of health care providers and moms-to-be, alike. In fact, a 2010 study published in the Journal of Women’s Health surveyed 93 practicing physicians and certified nurse midwives, finding that 64 percent believed that maternal exercise heart rate should not exceed 140 BPM. So, with that in mind, we explored what you need to know about your heart rate and exercising during pregnancy.
If you’re looking for pregnancy-safe exercises, look no further than Aaptiv. We have classes created by pre- and postnatal certified trainers.
Your body knows how to adapt.
Deepa Arla, D.O., a board-certified internal medicine physician at Shift medical practice in Chicago, says that women with no medical contraindications or risks, such as high blood pressure, heart disease, or uncontrolled diabetes, don’t need to focus on heart rate.
“If you exercised vigorously before pregnancy, your body is already adapted to that type and intensity of exercise, and it will continue to adapt,” says Arla.
The current Department of Health and Human Services guidelines actually recommend a minimum of 150 minutes a week of moderate-intensity aerobic activity (ideally spread throughout the week) without any specific heart rate limits.
Pay attention to how you feel.
Charlotte Hilton Andersen, 39, a writer from Denver, exercised throughout three of her five pregnancies. She participated in some of her favorite intense workouts like kickboxing, dancing, and weightlifting. With her OB-GYN’s blessing, she did not monitor her heart rate, instead focusing on how she felt.
“I found that my body was really clear about what it needed and when it needed rest,” says Andersen. “As long as I felt fine, I knew the baby was also fine. By the end, I naturally had to tone down the intensity as fatigue began to set in, but I still kept moving.”
If you find yourself getting fatigued more easily, tone it down with a walk, a stretch, or a meditation. Aaptiv offers classes in all three categories.
Andersen noticed a clear difference between the pregnancies where she was highly active and the ones where she was more sedentary. “I gained a more reasonable amount of weight, had more energy and recovered faster with the pregnancies I exercised through.”
Pregnant women naturally have a higher BPM.
Renee Jeffreys-Heil, Ph.D., RECP (registered clinical exercise physiologist), an assistant professor of exercise science at Florida Gulf Coast University and co-author of Fit to Deliver: An Innovative Prenatal and Postpartum Fitness Program, notes that the old 140 BPM guideline isn’t just unwarranted, it’s not especially feasible.
“The average resting heart rate of an adult woman who is not pregnant is normally 60-80 BPM,” she says. “Pregnant women, towards the end of their third trimester, tend to have a resting heart rate of about 110. If you are supposed to stick to a heart rate of 140 while exercising, that means you can only let it raise a small amount.”
A higher BPM leads to post-activity benefits.
Getting the heart rate up is one of the many ways exercise works its medical magic. “When you exercise, your heart rate increases. Then post-activity, your heart rate and blood pressure are actually lower than before,” Arla explains. “That’s one of the main reasons that exercising is so beneficial for cardiac health,” she adds.
Jeffreys-Heil recommends monitoring your perceived exertion, or how hard you feel you’re working out, as a way to gauge yourself. On a scale of zero to ten—ten being exercising at full capacity—“most people want to be in the five to seven range.”
Keep to a comfortable pace.
Never exercised? Pregnancy is the perfect time to begin moving. Experts recommend starting slow and sticking to a moderate intensity routine spread throughout the week. They also advise making sure that you can comfortably carry on a conversation while moving.
Red flags to watch out for: feeling dizzy or weak, chest pain and contractions. If you notice any of these, immediately stop exercising and call your OB-GYN, advises Arla. Otherwise, go get your sweat on!
Once you’ve made the decision to get your sweat on, get started with Aaptiv!
Plenty of athletes perform while pregnant.
Think about it: Serena Williams won her seventh Australian Open title while expecting; Olympic medalist Dana Vollmer swam the 50-meter freestyle at a national meet while six months pregnant; and elite runners Kara Goucher, Deena Kastor and Paula Radcliffe all continued to race, despite carrying mini future marathoners in their bellies.
As always, consult with your doctor or OB-GYN before starting any kind of fitness routine while pregnant. If you were exercising before pregnancy you can most likely continue exercising during pregnancy without worrying about complications.