Exercising during pregnancy

By Dr Shelley Rowlands, East Melbourne Obstetric Group

We know there are many benefits of regular exercise for pregnant women. Your body will be fitter and able to withstand the physical changes of pregnancy and the rigours of childbirth; exercising during pregnancy is associated with shorter and less complicated labours.

Being fitter will help you adapt to the physical demands of being a new mother. Regular exercise prevents excessive weight gain and reduces the risk of developing gestational diabetes. It may also reduce the risk of other pregnancy complications like pre eclampsia. It positively promotes psychological well-being and may reduce the risk of postnatal depression. Not only will it help during pregnancy but the effects will carry on long after you have had your baby; you will be less likely to develop heart disease, diabetes and some cancers.

Before you start

Not everyone can or should embark on a marathon immediately after the pregnancy test is positive. There may be some good medical reasons that existed before you became pregnant that may effect your exercise capacity, for example, if you have significant heart disease, bone or joint problems or severe lung disease. There may also be conditions that develop or become apparent during pregnancy that will effect the kind of exercise you do. Women who are at risk of premature labour ( they have had a baby prematurely before, or they are known to have a short cervix, or have had ruptured membranes or heavy bleeding during pregnancy, or have a multiple pregnancy) will likely be advised to reduce their exercise and activity during pregnancy.

While exercise can help control high blood pressure, some women will develop a condition associated with high blood pressure in pregnancy called pre eclampsia and they will likely need to rest more. If the baby’s growth is found to be slow (often called growth restriction) this can be an indication that the placenta is not functioning optimally and women will asked to reduce activity and rest more. If you develop severe anaemia during pregnancy it will limit your ability to exercise. In these, and other cases, advise around your exercise program will need to be individualised. Your doctor will help decide if an exercise program is suitable for you and hopefully it can be followed during pregnancy and after you have your baby.

How much, how often and what kind.

Healthy pregnant women are encouraged to be active active on most, preferably all, days each week. Overall you should try to fit in between 3-5 hours of moderate exercise or 1.5 to 2.5 hours of more vigorous exercise or a bit of both, a week. Ideally you should incorporate some muscle strengthening exercise on a couple of days. It is also important not to remain sedentary during the day, so incidental exercise and avoiding long periods of sitting is important.

If you are very overweight or have not been active at all before it will be better to start slowly and gradually increasing the amount and time , maybe every second or third day with rest on the days between.
Exercising between 30 to 60 minutes a time is usually about right. You can do longer if its very light, for example gentle walking. Again for women unused to exercise, 15 to 20 minutes is a better place to start.

The intensity of exercise will depend on your fitness , previous exercise routine and of course physical limitations. If you have not been active before pregnancy you should aim to get to a moderate level during pregnancy and previously moderate exercisers can continue at this level. The advise for women who have been active at very high intensity levels is less clear.

There is no evidence that vigorous exercise during pregnancy is harmful to you or your baby, provided you make changes to ensure you are comfortable and can tolerate the exercise. Maintaining your pulse rate at a given level is a difficult way to regulate exercise intensity. A better guide is the “ talk test”; you should be able to talk while you undertake moderate exercise. If you need to pause for breath during conversation, this will be more likely vigorous exercise. Regardless of the exercise always ensure you are well hydrated and eating nutritious food.

Both aerobic and strengthening exercises can be performed safely in pregnancy. Aerobic exercise uses large muscle groups over a period of time and will elevate your heart and breathing rate. For example brisk walking. The stationary bike and swimming are excellent aerobic exercises that can be continued throughout pregnancy. There is no reason that if you like to run, that you can’t continue this during pregnancy.

Strengthening exercises with weights or bands are considered “moderate” intensity exercise. They should not be performed lying flat on your back after the first trimester of pregnancy. You should take care in regard to the heaviness of weights lifted ( i.e. not be straining) and some type of strengthening exercises should be avoided ( e.g. lunges) particularly if you have preexisting back problems or have developed pelvic instability during pregnancy.

And whilst we’re on exercise- don't forget your pelvic floor. Pregnancy and child birth are significant stressors. Exercise programs that improve core strength, such as pilates, will help maintain your pelvic floor integrity and help prevent incontinence after birthing.

It can feel different

During pregnancy changes occur to your body to accommodate the growing baby: your heart will beat faster, your blood pressure will be generally lower, your respiratory rate will increase, your body shape will change, putting pressure on you core muscles and back, and of course you will gain weight. All of these things will effect how you feel during exercise.

Lower blood pressure may make you feel more dizzy- when you get up from lying down, do it slowly, and stop exercise gradually rather than suddenly.

Your higher pulse rate of pregnancy will become even higher with exercise and you may feel like you have “ palpitations”. Reduce your exercise to a level where you feel more comfortable.

As you gain weight and your centre of gravity moves ( forward!) in later pregnancy you will find that walking and weight bearing exercises are less comfortable. Swimming or the stationary bike are often better options at this time. Ligament laxity occurs in pregnancy and may lead to injury. Stretching is important and exercises that involve jumping should be avoided.

Pregnancy may be the first time you have thought about exercising. Some women are nervous about exercise during pregnancy. However regular exercise in pregnancy has never been shown to be harmful to either the mother or the developing baby. Moreover it is known to promote physical and mental health during pregnancy. With guidance you can choose the right exercise for you to enjoy and feel confident performing, knowing it will be beneficial for you and your growing baby.

Note: The views and advice expressed on this blog post are those of the author and are not representative of the Pregnancy Babies & Children's Expo.

Gain more Parenting Insights at our Expos

Get your Expo tickets today! View Expo dates