As a fun addition to my doula and childbirth education work, I have recently been training to become a pregnancy fitness educator. Pretty soon I’m going to start offering classes for moms who want to stay fit and limber during their pregnancies, and who want a little guidance, as well as a group to join, in order to do it. All of the reading that I’ve been doing as part of this training has made one thing abundantly clear – exercise during pregnancy is (for the vast majority of women) a good thing. Today I’ll be talking about the physical benefits of exercise for mom and baby (mom may be doing the exercise, but everybody wins!) and then in part two of this post I’ll delve into the less well-known, but equally important concept of body trust and why it matters for pregnancy, birth and the postpartum.

What constitutes safe and effective exercise for pregnancy?

*Disclaimer: any exercise program should be discussed with your healthcare practitioner in advance. They will let you know if there is any reason that you should not attempt a particular type of exercise or if you should limit it in terms of intensity, duration or frequency. Every body is different and the information here is intended for general use in healthy pregnancy.

When it comes to exercise, almost any sort will be good as long as you enjoy it, you’re doing it at a skill and endurance level that makes sense for you as an individual and you’re listening to your body while you do it.

Walking has long been touted as one of the best exercises for pregnant women and it remains an excellent choice. It’s something that almost everyone can do, it requires very little cost or equipment and it’s easily tailored to the individual and to the circumstances. If you’ve never exercised before, start with short strolls and gradually work up to a quicker pace and longer distances. If you’re used to intense workouts but are feeling fatigued because of first trimester exhaustion or third trimester mobility limitations, you might still be up for a walk even if you’re not up for your usual run or cardio session. On an energetic day, you can reap a ton of benefits by going for a power walk.

Swimming too is a form of exercise that many people are able to do with reasonable skill and that can also be easily adjusted. It also has the added benefit of taking gravity off of the bones and joints, making it especially desirable for the later weeks of pregnancy for many women and for those who may have back or knee problems. In the warmer months, it can be done outside, which, as with walking, means fresh air for you and your baby. Most pregnant women find themselves overheated during pregnancy, so a refreshing dip is often welcome. Many people swear by the practice of doing handstands in water as a way of turning a breech baby too! (There are even some studies that have shown this technique to have merit.)

In recent years, prenatal yoga has surged in popularity, with classes for a variety of skill levels popping up all over North America. Yoga is great for balance and flexibility and can be a godsend for days when your back is acting up or you’re feeling sore from a more intense workout earlier in the week. ‘Flow’ styles of yoga can even get the heart rate up, meaning that you’re getting some good cardio too. Many yoga poses are recommended for all pregnant women (whether or not you’re engaging in an exercise program) because they are so beneficial for foetal positioning, strengthening the pelvic floor and relieving discomfort. These may include cat/cow pose (also known as the pelvic tilt outside of yoga classes) or chair pose (kind of a squat).

Aside from walking, swimming and yoga, which are commonly accepted forms of exercise for pregnant women, there are countless other ways to benefit from moving your body during your pregnancy. There tends to be a lot of misinformation out there about more strenuous forms of exercise during pregnancy, but in fact, things like running, aerobics, dance and cross-country skiing are all very good for you, provided that you are working out at a level that is appropriate to you and are listening to your body before, during and after workouts (stopping and letting your HCP know if you experience any dizziness, pain, excessive fatigue, vaginal bleeding, contractions, headache or anything else that strikes you as ‘not right’). Many people believe that you shouldn’t start an exercise program during pregnancy if you have not been exercising before pregnancy. Not true! There are significant benefits to beginning at any time. Similarly, many people are under the false impression that exercise should stop in the third trimester. In actual fact, many of the benefits of exercising throughout pregnancy are most significant if exercise is continued until near birth.

What are the physical benefits of exercise during pregnancy?

I’ve already alluded to many of the great reasons to exercise during pregnancy above, for example reducing the discomforts of pregnancy such as back  and hip pain, increased flexibility and improved balance. In addition to these things, exercise, especially weight-bearing exercise like power walking, running, aerobics and dance, can have positive impacts on labour and birth, as well as on the health of the placenta and on neonatal outcomes.

Studies have shown that women who exercise regularly to moderate or high intensity for at least 20 minutes per session throughout their pregnancies are less likely to go past dates (though no more likely to experience pre-term birth) and tend to have shorter, easier labours. Studies have found a 35% decrease in requests for pain medications in labour among women who exercise regularly during pregnancy, as well as a 70% lower rate of maternal exhaustion in labour and a 50% decrease in artificial rupturing of membranes (breaking your waters to speed progress). Women who exercise reduce the likelihood of all medical issues and interventions in their labours – premature rupture of membranes, synthetic oxytocin (Pitocin), foetal heart-rate issues, assisted deliveries and Caesareans. They also tend to have larger placentas and leaner babies (that is, these babies have healthy birth weights, but less of their weight is from fat). Rates of gestational diabetes are also reduced. These women are also more likely to stay within a healthy weight range during pregnancy and are more likely to resume regular exercise after the baby is born. Women who exercise after the birth (within reason: see my earlier post The Race to the Bottom for more on caring for your whole self postpartum rather than focusing on losing the baby weight) are less likely to experience postpartum depression.

That is a very long list of benefits indeed! What about risks? It is well-known that stress due to physical occupations that involve long periods of standing, working for long hours or frequent heavy lifting are at risk of having low-birth weight babies, premature births, pregnancy-induced hypertension and placenta problems, such as placenta previa (when the placenta covers or partly covers the cervix at term), poor placental growth or placental abruption (when the placenta detaches from the uterine wall). None of these issues are associated with recreational exercise though, even when it is of an intense, weight-bearing nature (such as running). Work-stress tends to lead to extreme fatigue which is a reflection of dehydration and nutrient depletion and these are linked to the pregnancy complications listed above.

One thing that I find truly amazing is the complimentary nature of pregnancy and exercise. During pregnancy, a woman’s blood volume increases as does her body’s ability to get rid of excess heat through increased sweating and increased respiration. Exercise causes similar phenomena in the body: our blood pressure goes up, we breathe more heavily and we sweat. Similarly, both the conditions of pregnancy and of exercise increase the use of fat as an energy source. When pregnancy and exercise are combined the increased maternal reliance on fat for energy improves the availability of glucose and oxygen for the placenta and also suppresses stress hormones, which minimizes the decrease in uterine blood flow during exercise. This should not be surprising, but what is often surprising is that when it comes to athletic training, getting pregnant, exercising through pregnancy and then resuming training post-birth actually leads to a greater improvement in muscle tone, strength and overall fitness than exercise alone. In other words, the conditions of pregnancy make athletes who continue to train while pregnant into better athletes than they would be if they were never pregnant!

Whatever your reasons, if your healthcare provider has given you the go-ahead to exercise during pregnancy you are doing yourself and your baby a big favour when it comes to straight up physiological benefits.

There’s more though. Exercise also leads to increase body trust, which is hugely beneficial as well. In part two of this post I’ll be talking about what the term body trust means and why it matters for you, your baby, your labour and birth and the postpartum phase.