“May your choices reflect your hopes, not your fears.” Nelson Mandela
Pregnancy and Exercise – Not Just Swimming and Yoga Anymore
If this is your first or even your fifth pregnancy, you may be hearing some of these outdated but still circulating myths about pregnancy and exercise:
- Don’t lift anything heavy or overhead.
- Don’t let your heart rate rise above 140 bpm.
- Moms who aren’t active before pregnancy cannot start working out during pregnancy.
- Strength training should be avoided because it causes joint injury.
- Running should be avoided.
- All sports should be given up during pregnancy.
While at one point these myths were all treated as fact by the medical profession, research studies have debunked most of them.
First of all, we all know the following information is only intended for women with normal, healthy pregnancies who have been cleared by their doctors, right? Right.
How Exercise Affects Your Baby
It’s normal to be concerned with how exercise will affect your baby. Will the baby be injured with all the movement? Will your body get too hot? Will you fall and cause the placenta to rupture?
Much of this article is based on the studies of James Clapp, MD. Dr. Clapp has been conducting extensive scientific research in the field of maternal exercise and pregnant athletes for many years, and is generally considered one of the leading authorities on the subject. You can read more about his current recommendations based on the outcome of his studies in his excellent book, Exercising Through Your Pregnancy.
Back in the 80’s the American College of Obstetricians and Gynecologists (ACOG) recommended that exercising women not let their heart rate rise above 140 beats per minute during pregnancy. Even though they later revised this, the original recommendation is still commonly and mistakenly considered to be true. If you’re an athlete, this number can be quite frustrating to follow as this range would barely be considered a warm-up by your own normal standards. Therefore, heart rate is probably not an accurate gauge for maternal exercise. It is much more accurate to measure your level of intensity, also known as your Rate of Perceived Exertion (RPE).
Mother’s Body Temperature
During exercise the body temperature rises, and is also affected by other factors like the temperature of the environment (exercising in heat). Studies have shown that pregnant women who are athletic are more efficient at regulating their body temperature, therefore preventing the temperature from rising to dangerous levels. Clapp recommends not allowing more than 3 degrees Fahrenheit above normal, and taking the greatest precaution in the first trimester when the fetus is more vulnerable to the effects of overheating.
Oxygen Delivery to Baby
Is the baby getting enough oxygen during exercise? Babies become conditioned to the effects of exercise, increasing their ability to deal with the stress of not only each workout but later of labor and delivery. Therefore, a fit mother who was active before pregnancy can continue to exercise at her pre-pregnancy level. As long as she is doing this regularly and without reaching total exhaustion or holding her breath, she will not need to worry about the baby getting enough oxygen. Babies of out-of-shape mothers are only at risk of oxygen deprivation if their mother exercises at levels of intensity that they are not used to. So if you are new to exercise or haven’t been active in some time and are pregnant, it is best to start out slowly and work up to a level that is mild to moderate – you should be able to carry on a conversation while you work out. No matter your athletic level, never push yourself to the point of total exhaustion while you are pregnant.
Benefits of Exercise For Baby
In the past, the focus has been on the minute risks of prenatal exercise, and this has created unnecessary fear in expecting mothers. Take a look at these proven benefits to your baby:
- Babies whose mothers exercise have a lower heart rate, a sign of good heart health. Not only do the babies have a lower, more efficient heart rate while in utero, they continue to have lower heartbeats all the way up until at least age six and likely into adulthood, according to this study and this study.
- Moms who exercise during pregnancy tend to have babies with a healthier weight and are less likely to develop childhood obesity.
- New research shows that moms who exercise during pregnancy have babies with more active brains, and follow up studies will determine whether or not this means that those babies will be more intelligent.
- Babies whose mothers exercise during pregnancy tend to be less stressed during labor and delivery, resulting in higher Apgar scores and less interventions.
- Exercise helps control blood sugar and lowers the risk of developing gestational diabetes, resulting in a lowered chance for baby to develop diabetes later in life.
- Exercise reduces stress to mother, and chronic stress has been shown in multiple studies to be harmful to baby’s development and increases risk of pre-term labor.
More and more doctors and medical caregivers are now realizing that the benefits of exercise during pregnancy far outweigh any risks, and in fact a sedentary lifestyle is the real risk in pregnancy.
Sports During Pregnancy
Athletes have babies every day, and do so after continuing their sport of choice throughout their pregnancy. If you are an athlete who plays sports, chances are that as long as it is a non-contact sport with a low risk of falling, you can continue safely under your doctor’s supervision.
Searching online, I’ve come across many stories of women who continued their sport of choice throughout their pregnancies. For example, Alysia Montano competed in the US Track and Field championships at 8 months pregnant, and photos of her running the 800 meter race went viral. While she received lots of supportive feedback and pats on the back, there was also a fair share of negative commentary from the public. I’ve experienced this firsthand: I stumbled upon a photo of myself
exercising at 7 months pregnant with a slew of comments like “That’s so dangerous!” “You should never do this while pregnant!” The photos were of me performing a broad jump burpee, which I had done about a million times prior to my pregnancy and plenty of times during. What may have looked scary to someone who has never performed this type of exercise and doesn’t know what it feels like was second nature to me, and I laughed because the little “hop” at the beginning that was so frightening could not have been more mundane. Some moms run track, some do burpees, some hit a punching bag (I did this too), some continue Crossfit, some run marathons. Athletes are typically highly in tune with their own bodies and know when something feels unsafe or unstable.
Sports become a risk for the pregnant athlete when they involve contact, speed, or a high risk of taking a big fall. While the baby is very well protected by the pelvis and the amniotic fluid, placental damage can occur when there is a strong collision with an object (like a ball), another player, or the ground, especially at a high rate of speed. Examples of sports to avoid: cycling, rock climbing, skiing, skating, hockey, etc.
Strength Training During Pregnancy
During pregnancy, our bodies release a hormone called Relaxin. No, that’s not just a term for takin’ it easy, but a real hormone that makes our joints and ligaments “relax” to accommodate the growing baby and to prepare the body for birth. Because of the increase in flexibility, rumors pervade that strength training is dangerous and pregnant women are more susceptible to injury. While this may be true in theory, Dr. Clapp and his colleagues performed a study with pregnant women who strength trained, and found no increased risk of injury when strength training was of mild to moderate intensity.
Women who already lift can continue their current strength training regime, but pregnancy is the time for putting aside any thoughts of PR’s and extreme lifting. This is relative – what may be a high intensity lift for one mom may be mild to another, so it’s up to each individual to assess their own capabilities, being careful to listen to their own bodies and never to push to the point of exhaustion. Modifications may be necessary as the pregnancy progresses to make room for the growing baby and to accommodate changing balance and strength.
If you’re new to strength training and would like to begin during pregnancy, like other exercise, start slow and light with the basics, make sure you can breathe enough to carry on a conversation, and work up to a mild to moderate routine.
To avoid injury while strength training during pregnancy, it’s more important than ever to maintain control and proper form. If you are unsure about proper form, it would be highly beneficial to hire a personal trainer who specializes in prenatal exercise for at least one training session.
Exercising On Your Back During Pregnancy
Aren’t you supposed to avoid lying on your back during pregnancy? After the first trimester, the weight of the uterus can sit right on a major vein, which could cause low blood pressure, faintness, and a decrease in oxygen to the baby. If you are exercising on your back and begin to feel nauseous or lightheaded, change positions immediately and see if your symptoms go away. However for most pregnant exercisers, according to Dr. Clapp, if you are moving your legs while on your back, your body should have normal circulation. If you are concerned, limit your time in this position to a few minutes.
Exercising the Core in Pregnancy
A strong point of confusion and debate amongst fitness professionals: should you work your core during pregnancy, and if so, how?
The first question I can answer definitively – yes, you should exercise your core, because having a strong core will lessen the likelihood of experiencing the typical aches and pains of pregnancy (lower back pain), improve your balance and posture, and help you immensely during labor and delivery.
The second question involves avoiding diastasis recti, which is a separation of the abdominal muscles caused by pressure from the growing uterus pushing against the abdominal wall. Certain exercises can worsen the separation, although which ones depends on who you ask. When I was pregnant, I tried to avoid any exercises that made my stomach muscles make a “cone” shape. This included crunches and anything that involved the motion of sitting straight up from lying down. While I did perform push-ups from plank position, I tried to hold in my abs tightly and not hold the position for any extended length of time.
Diastasis isn’t a serious condition, but can be annoying and sometimes painful. It can cause a protrusion of your belly long after pregnancy is over and a weaker core if it isn’t rehabilitated properly. While some information is available online (mostly for purchase), it’s probably best to seek the advice of a personal trainer or physiotherapist for the best ways to rebuild your pelvic and abdominal wall after pregnancy.
Fear and Decision Making
Hopefully the general fear of an active pregnancy is beginning to subside as more and more fit moms and scientific research prove that pregnancy can be not only active but athletic, but the myths are still rampant, as my inbox proves day after day.
I understand the fears regarding pregnancy as much as anyone. I lost my very first pregnancy at 23 weeks many years ago, and it was absolutely devastating. Somehow I convinced myself it was my fault for moving furniture, even though every doctor I saw after that said it had nothing to do with her death. My next pregnancy, I parked myself on the couch and didn’t move, thinking I would somehow protect this baby from the same fate. It was a miserable, uncomfortable pregnancy and a long, traumatic delivery because I was so out of shape (you can read more here).
By this last fit and healthy pregnancy, I was still afraid that working out would hurt the baby, but instead of letting my fear take over, I made informed decisions for myself based on the latest research, and chose to continue exercising at the same level I was used to. It was the best decision I ever made, and I felt so much more comfortable and “myself” throughout the pregnancy, bounced back almost immediately, and was able to have a natural birth.
No one, not even I, can tell you what is right for YOUR pregnancy. Whatever you decide, make sure it is a decision made from a combination of your instincts, facts, and research as opposed to fear, rumors, and misinformation.