The Importance of Strength Training During Pregnancy

By Sarah Percy, (Doctor of Physiotherapy, Bachelor of Exercise Science) 
Women’s Health Physiotherapist & Director, Female Physio Co

There’s a lot of noise - and confusion - around what’s safe when it comes to exercising during pregnancy, especially with strength training. Let’s clear that up. Historically, pregnant women were often advised to rest and avoid most forms of physical activity for fear of harming themselves or their baby. Fast-forward to 2025, and we now have a wealth of clinical research proving that not only is exercise safe during pregnancy, it’s vital. In fact, current evidence supports that staying active during pregnancy is one of the best things you can do to prepare your body for the demands of labour, delivery, and motherhood. 

Why Exercise Matters in Pregnancy

Pregnancy is physically demanding - your body is undergoing rapid and constant change.

Strength training specifically plays a key role in:

• Reducing pelvic and lower back pain
• Lowering the risk of prolonged labour and instrumental delivery
• Decreasing the likelihood of pre-eclampsia and gestational diabetes
• Reducing risk of macrosomia (larger-than-average baby)
• Supporting healthy maternal weight gain
• Lowering the chance of preterm delivery

Meanwhile, physical inactivity and excessive weight gain during pregnancy are known risk factors for maternal obesity and pregnancy-related complications - including Gestational Diabetes Mellitus (GDM). GDM occurs when fluctuating hormones reduce the effectiveness of insulin, leading to high blood glucose levels.

So, can you exercise during pregnancy? Yes, you absolutely can - provided there are no serious medical complications or contraindications.

When Not to Exercise During Pregnancy

Before starting any exercise regime during pregnancy, it’s essential to check in with your care provider - whether that’s your obstetrician, GP, or a Women’s Health Physiotherapist.

Contraindications to exercise include:

• Significant heart disease
• Restrictive lung disease
• Incompetent cervix or cerclage
• Multiple gestation at risk of preterm labour
• Persistent second or third-trimester bleeding
• Placenta previa after 26 weeks gestation
• Premature labour during current pregnancy
• Ruptured membranes
• Preeclampsia or pregnancy-induced hypertension
• Severe anaemia

These conditions require clearance from your obstetric care provider and careful monitoring.

How Much Exercise is Recommended?

As of March 2020, The Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG) updated their guidelines, recommending:

• 150–300 minutes of moderate-intensity exercise per week
• That’s approximately 30 minutes per day, on most (preferably all) days of the week

If you were previously inactive, it’s okay to start small - just 15–20 minutes per day - and gradually build up to the recommended duration.

How Hard Should You Be Working?

Pregnant women are encouraged to work within 60–80% of their maximum heart rate:

• If you were sedentary before pregnancy, stay towards the lower end
• If you exercised regularly before pregnancy, you may work at the higher end

A good rule of thumb? You should still be able to carry on a conversation during your workout – but again, this is only a guide.

Why Strength Training Is Especially Important

When it comes to exercise during pregnancy, strength training stands out as one of the most beneficial forms—both from research and clinical experience.

Here’s why:

1. Supports Your Changing Body 

As pregnancy progresses, your posture shifts, your centre of gravity moves, and your joints become more mobile (thanks to hormones like relaxin (only until 12 weeks gestation), oestrogen and progesterone). These changes can lead to discomfort or injury if your muscles aren't strong enough to support them.

Strength training helps:

• Support your pelvis and lower back
• Improve posture
• Prevent or ease pelvic girdle pain, pubic symphysis dysfunction, coccydynia, and low back pain

Reduce diastasis recti (abdominal separation) A strong posterior chain—glutes, hamstrings, and back muscles—is especially helpful in supporting your pelvis and spine.

2. Prepares You for Labour and Birth

Labour is often described as a marathon - so it makes sense to train for it like one.

Strength training:

• Improves muscular endurance and stamina
• Builds awareness of your core and pelvic floor
• Enhances your ability to push effectively during the second stage of labour
• May reduce the risk of assisted delivery or pelvic floor trauma

3. Boosts Your Mental Wellbeing

Perinatal depression and anxiety is real and can affect anyone, at any time.

Strength training has been shown to:

• Increase endorphins
• Reduce stress and anxiety
• Improve sleep quality
• Enhance confidence and body image

Feeling strong in your body during a time of immense change can be an incredible mindset shift - especially when facing fears around birth and new motherhood.

4. Sets You Up for a Smoother Postnatal Recovery

Think of pregnancy as the pre-season training for motherhood.

Strength training helps you:

• Lift, carry, and care for your baby with less strain
• Minimise postpartum issues like back pain and wrist injuries
• Rebuild core and pelvic floor strength for return to sport or high-impact activity

Focus on What You Can Control

Pregnancy brings a wave of changes - many of which are outside your control. But staying active is something you can choose, and it’s one of the most empowering choices you can make for yourself and your baby. If you’re unsure where to start, I always recommend booking a session with a Women’s Health Physiotherapist. Together, we can help tailor a safe and effective strength training routine suited to your stage of pregnancy, lifestyle, and health history.

You deserve to feel strong, supported, and confident throughout your pregnancy journey.

Ready to start your journey? Join our Pregnancy Program today!

References

March 2020, Exercise during Pregnancy, The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

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.