A: Not usually. Exercise in pregnancy is important, although some exercises aren’t recommended.
It’s tough being pregnant; in addition to nausea, exhaustion and swollen ankles, pregnant women are often overwhelmed with conflicting information on practically everything from eating salad to exercising.
We all know exercising is essential for a healthy lifestyle, but many pregnant women feel nervous about physical activity for fear it may harm their unborn child. So can exercising while you’re pregnant be dangerous?
The vast majority of pregnant women can safely enjoy some level of sport or physical activity throughout their pregnancy, says Dr Anita Green, sports doctor and spokesperson for Sports Medicine Australia.
But, because of normal changes to a woman’s body during pregnancy, there are some issues that need to be considered when exercising during pregnancy. This is why Green says it’s important to talk to your doctor, or midwife, about the best exercise for you in your pregnancy.
Some of the things to discuss include the type of exercise you like to do, your general fitness levels, any complications with your pregnancy and how much exercise you did before you conceived.
“Most pregnant women will be healthy and have a pregnancy which is progressing normally. For them it is most important that they continue to be physically active for their own physical and mental health and the wellbeing of their baby,” she says.
Even if you weren’t exercising regularly before you conceived, you can start a safe and appropriate exercise program during pregnancy.
Pregnant women who exercise have better weight control, improved mood, decreased constipation and they maintain their fitness. Exercise also helps prevent the onset of gestational diabetes (diabetes that occurs during pregnancy) and is recommended for women who develop gestational diabetes.
There are still some things to bear in mind before you put your walking shoes on, though. We teach this to our students during our Certificate III and IV courses in Fitness. See below for more information.
Avoid overheating – it is recommended that pregnant women avoid overheating while exercising. When you’re pregnant your core body temperature increases; it’s thought that further increases in temperature brought on by exercise could be harmful to the baby.
There is some evidence to support this suggestion in research that found the babies of women who use hot saunas and spas during pregnancy may be at increased risk of foetal malformations. So it’s a good idea to consider choosing cooler times of the day to exercise, exercising in an air-conditioned gym or getting into the water to work-out.
Watch your heart rate – it’s best to exercise at a moderate intensity, Green says, as prolonged intense exercise can reduce blood supply to the placenta.
What is moderate intensity? Well your resting heart rate is increased during pregnancy, so don’t rely on heart rate to determine how hard you are working. Instead, try to be aware of how hard you feel your body is working.
“You should still be able to ‘whistle while you walk’, cycle or use the gym,” Green says.
As a guide, try not to exercise at moderate intensity for any longer than 45 minutes at a time, and if you want to exercise for longer then go at a slower pace. You also need drink plenty of water.
“[But] if women do experience abnormally fast heart rates during exercise, are aware of palpitations or their heart rate is slow to recover after exercise then they should see their doctor.” Green says.
Avoid lying on your back – it’s not advisable to exercise lying on your back after the first 13 weeks of pregnancy (the start of the second trimester). Lying on your back can allow your uterus to press against a large vein, which returns blood from your legs up to you heart (the inferior vena cava), and this pressure may significantly lower your blood pressure.
Avoid injury – during pregnancy your body produces a hormone called relaxin, which “relaxes” your ligaments, allowing you to deliver your baby through your pelvis during birth. The downside of relaxin is that pregnant women are at higher of joint injuries, such as sprains.
To ensure you minimise your risk of joint injury during pregnancy avoid high impact activities (such as jumping), activities where you change direction frequently, or any over-stretching – especially in the last 13 weeks.
From around the fourth month, try to avoid rapid changes of position – such as bending over and standing up quickly – to reduce your risk of dizzy spells. If you’re experiencing back pain, dial down the intensity of your work-outs or take to the water.
Avoid falls – your changing shape also affects your balance, which puts you at risk of falls. This is why pregnant women are often encouraged to avoid activities such as skiing, horse-riding or rollerblading. (Although if you’re a keen and competent skier, or something similar, then you should speak to your doctor if want to continue these activities).
If you’re wondering where to start your pregnancy exercise program, walking is your best and safest option. The added bonus is that there are opportunities to walk almost anywhere and it does not involve any special equipment apart from a comfortable pair of walking shoes, Green says.
It is also safe to swim throughout pregnancy and is popular because the pregnant abdomen is well supported, and it avoids the risk of overheating.
Stationary cycling at the gym would also suit most pregnant women, Green says.
But it’s also worth noting that sometimes complications do arise in pregnancy.
“A healthy uncomplicated pregnancy may have few restrictions placed on the type and amount of exercise that can be done. Other situations may arise that require exercise to be restricted or completely ceased,” she says.
If you experience any of the following when exercising, stop the activity and see a doctor immediately: