In the past, pregnant women were discouraged from exercise. Pregnancy was seen as a time to put your feet up and take it easy. But this historical view of pregnancy was very much based on cultural and social biases rather than scientific evidence.
These days, we're increasingly recognising the benefits of regular physical activity during pregnancy: reduced fatigue, fewer physical discomforts of pregnancy and enhanced aerobic fitness, which is particularly important when considering that pregnancy culminates in labour and delivery of a baby – a physical endurance event like no other! Women who are active during pregnancy seem to have lower rates of medical intervention during labour.
There's also the added benefits of reducing stress, anxiety and depression and avoiding excessive weight gain.
What type of exercise?
You might be surprised to learn that exercise guidelines for pregnant woman aren't too dissimilar to those for the general population. In general, women with a healthy pregnancy (no complications) should aim for 30 to 45 minutes of aerobic exercise three to five times per week. Aerobic exercise means low-impact activity such as brisk walking, stationary cycling and swimming or water-based exercise.
The intensity should be kept moderate – so it should feel "somewhat hard" but not "hard". A good guide is to exercise at a level where you can still comfortably hold a conversation.
If you haven't been a previous exerciser, it's still okay to make a start during pregnancy, provided it's gradual. As little as 15 minutes of aerobic exercise three times per week is a great start, gradually increasing to 30 minutes four times per week over the course of the second trimester. Try going a few extra minutes each week.
Things to avoid
This is mainly common sense, but there are some specific precautions you should take:
• Avoid exercise in particularly hot or humid environments – this can impair the baby's development in the first trimester
• Avoid high-impact exercises and activities involving sudden changes in direction such as competitive court/field sports – the risk of injury is greater during pregnancy due to hormonal changes loosening the joints and the extra load being carried
• Limit exposure to activities that involve a risk of falling or impact to the belly – balance is impaired due to changes in the centre of gravity
• Avoid exercises involving lying on the back after the first trimester – the enlarged uterus can impair blood flow back to the heart.
So, is running okay?
This should be decided on an individual basis. Running can be okay for a woman with an uncomplicated pregnancy if she was a regular runner before pregnancy – provided that she listens closely to her body and does not overdo it (and has a strong pelvic floor!).
For women who weren't regular runners prior to pregnancy, this isn't the time to start.
Pregnancy is not a time to reach peak fitness or train for athletic competition, but it's possibly the most important time to adopt a healthy lifestyle. The benefits gained from physical activity affect both the mother and the future health of her unborn child.
If you have complications with your pregnancy – such as a low lying placenta or impaired growth of the baby – talk to your health provider about what type of activity you can take on.
Explore further: Three in four women below recommended exercise levels during pregnancy, research shows