A guide to exercising in pregnancy

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For much of recent history, pregnant women were advised to put their feet up and avoid physical exertion for fear of hurting baby.

But these days, we're increasingly aware of how exercise in pregnancy can benefit both mum and bub: moving more can ease or prevent back pain, boost your mood, help you sleep better, prevent excess weight gain, and help your body prepare for the physical demands of labour. Studies have shown that exercising while you're expecting can also reduce rates of medical intervention during labour.

And that's not all: there's also evidence to suggest that exercising during pregnancy can decrease the risk of gestational diabetes and pregnancy-related high blood pressure, as well as reduce the symptoms of postpartum depression. 

Most mums-to-be should aim to meet the recommended exercise guidelines for all people – pregnant or not – of at least 30 minutes per day. As your pregnancy progresses, you'll need to make a few adjustments to accommodate your growing bump – and swap out some types of exercise that aren't recommended.

First trimester

During the first trimester – and throughout your pregnancy – it's best to maintain moderate intensity workouts and avoid getting too hot, which raises your body temperature and can impair the baby's development.

"During the first trimester all of the baby's major organs are developing so it's good, even if you feel fantastic, to modify your exercise so you're working at a mild to moderate level rather than at a high intensity," says physiotherapist and fitness instructor Lisa Westlake.

"You don't want to get too hot because studies have demonstrated that might not be good for the baby's organ development. On a scale of 0-20, you should be exercising at a level of about 13 or 14, whereas when you're not pregnant you should be aiming for 17."

If you were a regular exerciser before falling pregnant, you'll probably be able to continue working out in your activity of choice during the first trimester.


And if pregnancy has motivated you to get moving for the first time in years, it's best to start slow.

"Some women find that when they fall pregnant that it is the motivation and inspiration to start thinking about starting to exercise," says Westlake. "That's absolutely fine, as long as you start slowly and work within the guidelines for safe and effective exercise during pregnancy.

"A women starting out would do less than a women who's been exercising prior to her pregnancy, but everyone can benefit from exercise during pregnancy."

If you haven't already, the early stages of pregnancy are also the best time to begin exercising an invisible set of muscles: your pelvic floor. Strengthening the pelvic floor will help your body cope with the growing weight of the baby and reduce the risk of post-birth incontinence.

Second trimester

As your pregnancy progresses your resting heart rate and blood pressure increase, which may mean you need to slow down at the gym or in the park to avoid overheating.

"You might find you were okay to be running in the first trimester but once you get to the second trimester you're out of breath," says Anita Hobson-Powell, CEO of Exercise and Sports Science Australia. "Use the talk test as a guide to moderate activity – if you can do the activity and still talk while you're doing it, you can continue."

Many experts recommend that pregnant women avoid activities with an increased risk of injury and falls, such as contact sports, horse riding, skiing and road cycling. The risk is thought to increase as your pregnancy progresses because of your changing centre of gravity and hormonal changes that loosen your joints. But according to Sports Medicine Australia, there is no research to support these concerns.

The organisation says it's best to discuss your exercise regime with your GP, who can help you make a decision on whether to continue playing netball or cycling to work based on your personal history.

Dr Gary Swift, a Gold Coast-based obstetrician and vice president of the National Association of Specialist Obstetricians and Gynaecologists, agrees. "Here on the Gold Coast there are a lot of women who like surfing and keep surfing through pregnancy. But there is always the risk of a fall, so everyone has to look at their own risk profile and capabilities and readjust their expectations of how their body will perform."

After the 16-week mark of pregnancy you should avoid exercises that involve lying on your back, as the weight of the baby can slow the return of blood to the heart.

Third trimester

Working out during the third trimester can be difficult as your belly is larger and you're probably feeling more tired, so it's more important than ever to listen to your body on the home stretch.

"It really comes down to how you're progressing," says Hobson-Powell. "Most women at this time are coming down to lower intensity exercise as the heart rate and blood pressure increases.

"Walking, yoga, Pilates and water aerobics are usually better during the last trimester."

Stop exercising and see your doctor if you experience any worrying symptoms during an exercise session, such as dizziness, headache, increased shortness of breath or chest pain.

"You've got to feel comfortable and invigorated at the end of a workout," says Dr Swift. "Listen to your body and your body will tell you if you're trying to do too much."