Is it safe to exercise in pregnancy?

When it comes to exercise in pregnancy, there are many opinions and theories that go around about what is and isn’t safe. It can be quite overwhelming especially if this is your first pregnancy.

Historically, pregnant women were typically advised to rest in order to avoid the risk of harming them or their baby. Fast-forward to 2020 and research guidelines are changing more rapidly than ever. Why? Because we now have scientific proof to show the benefits of physical activity during pregnancy for both you and your baby.
Given the physical demands of labour and delivery, it is important to maintain your physical strength and function to help you through this time. Exercising in pregnancy helps to reduce pelvic and lower back pain, reduces your risk of prolonged labour and instrumental delivery, reduces the risk of pre-eclampsia, reduces the risk of macrosomia (where the baby is born much larger than average), reduces the risk of pre-term delivery, helps to control maternal weight gain and reduces your risk of gestational diabetes.

Maternal and fetal benefits of exercise during pregnancy. Extracted from Bo et al., 2016, 2017, Silva et al., 2017, Haakstad et al., 2018. Green indicates moderate to high evidence, yellow indicates low evidence.

Following this, physical inactivity and excessive weight gain have been recognized as independent risk factors for maternal obesity and pregnancy related complications including Gestational Diabetes Mellitus (GDM). This is where the fluctuating pregnancy hormones cause the insulin in your body to work less effectively which then causes high blood glucose levels.

So, the short answer is YES you can exercise in pregnancy…BUT, only in the absence of serious medical complications or contraindications.

Reason’s you SHOULDN’T exercise during pregnancy

It is always best to check in with your obstetric care provider first (Obstetrician, General Practitioner, Women’s Health Physiotherapist) first to ensure you are cleared to exercise before commencing prenatal exercise. The most common medical conditions where exercise is contraindicated in pregnancy are:

  • significant heart disease
  • restrictive lung disease
  • incompetent cervix or cerclage
  • multiple gestation at risk of premature labour
  • persistent vaginal bleeding
  • placenta previa after 26 weeks gestation
  • premature labour during the current pregnancy
  • ruptured membranes
  • preeclampsia or pregnancy-induced hypertension
  • severe anemia

This is something that needs to be discussed with your medical team prior to commencing any form of exercise.

How much exercise should I be doing?

In March 2020, The Royal Australian and New Zealand College of Obstetricians and Gynaecologists updated their guidelines on exercise in pregnancy. They state that pregnant women should aim to be physically active on most, preferably all days of the week. They elaborate further by saying that you should aim to accumulate 150-300 minutes of moderate intensity exercise per week, that’s around 30 minutes of exercise daily. If you were previously inactive prior to pregnancy, you should start with 15-20 minutes of exercise with the aim to build up to 30 minutes.

How hard should you push yourself?

The recommended heart rate zone during pregnancy is 60-80% of maximal aerobic capacity. If you were sedentary prior to pregnancy, you should work at the lower end of this zone and if you were accustomed to regular exercise before pregnancy, then you may work at the upper limit. Have a look at Table 1 for appropriate heart rate zones according to your age. I like to encourage my patients to do the ‘talk test’ to determine if the exercise intensity is moderate or vigorous. If you are exercising at a moderate pace, you should be able to hold a conversation throughout the activity. If you are unable to do this during exercise, you are training at a vigorous pace.

Target heart rate zones for normal-weight pregnant women. Extracted from PARmed-X for pregnancy: Physical activity readiness medical examination, 2015, Canadian Society for Exercise Physiology, Ottawa, Ontario.

What type of exercise should I be doing?

Pregnant women are encouraged to participate in a mixture of aerobic and strength exercises throughout their pregnancy. Aerobic cardiovascular exercises include walking (at a brisk pace), swimming and stationary cycling. Strengthening exercises should be performed 2 x per week on non-consecutive days. I find strengthening the upper and lower body imperative for injury prevention during pregnancy, particularly around the hips, lower back and neck.

What about running?

The guidelines tell us that if you have been running prior to falling pregnant, then you may continue throughout your pregnancy provided you feel comfortable enough to do so and don’t experience any symptoms. If you haven’t run prior to falling pregnant, the guidelines tell us that the commencement of running should avoided in pregnancy.

However, there is no scientific evidence for this, so this still remains a grey area.

Focus on what you can control.

There are many changes that happen to your body when you’re pregnant, those of which some you cannot control. What you can control is your ability to improve and maintain your physical and mental health. I encourage all of my patients to find an exercise routine that you enjoy and will stick to throughout your prenatal journey. I highly encourage all of my patients to book a consultation with a Women’s Health Physiotherapist so they can guide you towards the safest way of keeping your body moving during your pregnancy.

References

March 2020, Exercise during Pregnancy, The Royal Australian and New Zealand College of Obstetricians and Gynaecologists. Full article
Bo, K., Artal, R., Barakat, R., Brown, W., Davies, G. A. L., Dooley, M., Khan, K. M., 2016, Exercise in pregnancy in recreational and elite athletes: 2016 evidence summary from the IOC expert group meeting, British Journal of Sports Medicine, 50(10), 571-589.
Da Silva, S. G., Ricardo, L. I., Evenson, K. R. & Hallal, P. C., 2017, Leisure-time physical activity in pregnancy and maternal-child health: A systematic review and meta-analysis of randomised controlled trials and cohort studies, Sports Medicine, 47(2), 2950317.
PARmed-X for pregnancy: Physical activity readiness medical examination, 2015, Canadian Society for Exercise Physiology, Ottawa, Ontario.