How to exercise when you are pregnant

The experts

• Dr Wei-Wei Wee-Stekly, obstetrician & gynaecologist, Gleneagles Hospital
• Amanda Lim, perinatal expert, metabolic health coach, and director of Lift Clinic

For someone who has never lifted weights before, is it safe to start strength training during pregnancy?

Dr Wee-Stekly: Yes, pregnant women can lift weights, and it is generally safe and beneficial for both mother and baby if done with proper modifications. Firstly, get medical clearance from your doctor before starting or continuing a strength training routine in pregnancy. Seek professional personal trainer guidance in the gym, especially if you are new to strength training, so that you can learn the proper and safe techniques for pregnancy. Do avoid supine exercise: Avoid lying flat on your back for prolonged periods, especially later in pregnancy.

You should modify the intensity by using a lighter weight and avoid lifting to absolute failure, focusing on maintaining strength rather than setting personal records. Remember to breathe properly, and avoid holding your breath while lifting (Valsalva Maneuver). Lastly, listen to your body, and reduce the workout intensity if you feel pain or discomfort.

Amanda: It is absolutely safe to start and continue resistance training and other exercise in pregnancy. Recent research out of Canada by exercise physiologist Margie Davenport found that women who were not active before pregnancy, but started being active in pregnancy, had the greatest reductions in pregnancy complications, including lower rates of gestational diabetes, hypertensive disorders, and excessive gestational weight gain.

The safest approach is to work with a certified perinatal fitness professional, especially in the beginning when you’re just starting to understand your pregnant body, and as your body undergoes more impactful physical changes towards the end of the second and third trimesters.

What are the benefits of staying active during pregnancy?

Dr Wee-Stekly: In my experience, women who remain active during pregnancy are better pushers during labour, recover faster after delivery, and have better post-partum urinary control. They also have a reduced risk of anxiety and depression, lower risk of gestational diabetes and pre-eclampsia, and regain their pre-pregnancy weight faster.

Strength training in particular can strengthen the abdominal and back muscles, which can reduce lower back pain and improve posture, as well as strengthen the pelvic floor and muscles needed for labour, potentially leading to faster delivery and improved postnatal recovery. It can also help manage weight gain and improve blood sugar control, reducing the risk of gestational diabetes. In addition, it can boost uterine blood flow, and this may improve the child’s metabolic health.

Amanda: Anecdotally, some of my clients have been able to manage their gestational diabetes with well-timed exercise interventions and a clearer understanding of nutrition. Others have sought my advice as second-time mums, and had decreased pain and increased energy because of my advice. And the biggest impact for me is when a mum tells me that she was able to avoid post-partum depression and anxiety because she carried her exercise habits into the “fourth trimester”.

Can exercise lead to miscarriage?

Dr Wee-Stekly: Low to moderate-intensity exercise does not cause miscarriage in normal healthy pregnancies. According to the American College of Obstetricians and Gynecologists, regular exercise is generally safe and beneficial for your body.

However, high-strain or high-impact exercise, particularly when excessive, has been linked in some studies to an increased risk of miscarriage. If you have a high-risk pregnancy, for example, a history of previous miscarriages or an incompetent cervix, please consult your doctor before exercising.

How should I tailor my workouts over the trimesters?

Dr Wee-Stekly: In the first trimester, focus on maintenance, staying hydrated, and managing fatigue or nausea. If you feel unwell, reduce the intensity or duration of your workouts. Avoid strenuous activity if you were not active before, high-impact activities with high fall risks (like skiing), and overheating.

The second trimester is often a high-energy phase, but the growing belly requires modifications for balance and safety. Avoid lying flat on your back for extended periods after 16 weeks to prevent dizziness and ensure blood flow to the baby. Shift from high-impact (jumping, running) to low-impact (swimming, cycling) to protect loosening joints. Avoid traditional crunches or twist motions; switch to planks, bird-dogs, or modified side-lying moves. Reduce the weight load if weight training and increase reps (12-15) to maintain muscle without overloading joints.

In your third trimester, focus on comfort, mobility, and reducing high-impact load as the body prepares for labour. Reduce intensity and duration, focusing on pelvic floor relaxation and mobility. Use props like pillows or benches for incline exercises if you are still on your back. Be mindful of balance, as your centre of gravity has shifted drastically. Include pelvic floor exercises (Kegels) and hip-opening stretches (cat-cow, butterfly stretch) in your routine.

Stop exercising and seek medical help if you experience:

• Vaginal bleeding
• Dizziness/fainting
• Chest pain
• Leaking liquid
• Painful contractions

Other warning signs include:

• Unexplained shortness of breath
• Calf pain/swelling
• Severe headache
• Decreased foetal movement

Exercise in pregnancy should be avoided totally if you have

• Vaginal bleeding
• Low-lying placenta
• Preterm premature ruptured membrane
• Preterm labour
• Incompetent cervix
• Severe anaemia
• Cardiac/respiratory diseases