First things first:
If you’re someone who lifts – whether that’s a weekly gym session, competitive powerlifting or Olympic weightlifting – finding out you’re pregnant can bring up a lot of questions and probably a lot of conflicting opinions too. You might hear “just walk” from one person and see someone squatting a personal best at 38 weeks on your feed the next. It can feel really hard to know what’s true, what’s safe and what’s right for your body.
So let’s look at what the evidence actually says – across all three trimesters, what’s changing and what that might mean for your training. It’s important to say upfront that every pregnancy is different and deserves an individualised approach. As an Accredited Exercise Physiologist specialising in women’s health, my hope is that this gives you something useful – not a rulebook, but an honest, evidence-informed starting point so you feel supported rather than confused.
Why Strength Training in Pregnancy is More Important Than You Think
Let’s start with why this matters.
A 2025 systematic review and meta-analysis published in the British Journal of Sports Medicine (Prevett et al.) analysed 50 studies involving over 47,000 participants and found that resistance training during pregnancy was associated with:
- Reduced rates of gestational diabetes
- Reduced rates of gestational hypertension and pre-eclampsia
- Lower rates of caesarean section
- No adverse effects on birth weight or gestational age
- Improved pelvic floor outcomes
These findings are not isolated. A 2023 meta-analysis (Giles et al., Women’s Health) looking specifically at aerobic and resistance exercise on blood pressure during pregnancy also found meaningful reductions in hypertensive conditions, which is a major contributor to maternal morbidity in Australia.
In other words: lifting isn’t just something you can keep doing. In many cases, it’s something you should be doing.
Trimester 1 (Weeks 1-13):
What’s Happening
The first trimester brings a lot of change, even if you can’t see it yet. Fatigue, nausea, and significant hormonal shifts are common. Your cardiovascular system begins increasing blood volume, your resting heart rate rises and the hormone relaxin starts to increase joint mobility throughout your body. It’s a big internal shift, even when things look the same on the outside.
What the Research Tells Us
Current guidelines from the American College of Obstetricians and Gynecologists (ACOG), updated in 2022, recommend that pregnant women without complications aim for 150 minutes of moderate-to-vigorous physical activity per week and note that weight bearing exercise can, in many cases, be continued at pre-pregnancy intensity throughout pregnancy. RANZCOG (2023) echoes this, noting that regular exercise in an uncomplicated pregnancy has no evidence of harm to mother or baby.
For most women who were already training before pregnancy, the first trimester is often the period where least needs to change. A few things worth being aware of:
- Heat: The main consideration around heat in early pregnancy is sustained core temperature above approximately 39°C which is more associated with passive heat exposure like hot tubs, saunas or fever than with exercise itself. Your body manages heat during training well through sweating and circulation. That said, training in very hot or humid environments is worth being mindful of – particularly outdoors in a Queensland summer. Staying hydrated and training somewhere comfortable goes a long way.
- Fatigue and nausea: These are real and they’re valid reasons to pull back. Your body is doing an enormous amount of work and honouring that is not a setback.
- Your individual health picture: Everyone’s pregnancy is different. If you have any concerns, bleeding or pre-existing conditions, a conversation with your obstetrician or midwife is always a worthwhile first step before continuing or starting a training program.
A Note on the Pelvic Floor
The first trimester is the perfect time to start building awareness of your pelvic floor – how it feels, how it responds to load and whether it’s something you’d like to explore further with a Pelvic Floor Physiotherapist. This awareness and education becomes increasingly valuable as pregnancy progresses and pairing that support with a women’s health Exercise Physiologist means you have a team that can look at the whole picture together.
In the next blog we’ll be diving into Trimesters 2 and 3 – including what the research says about heavy lifting, supine positioning and the Valsalva manoeuvre as your pregnancy progresses.
Written by Annie Daly, Senior Exercise Physiologist
References:
- Prevett C, Gingerich J, Sivak A, Davenport MH. Resistance training in pregnancy: systematic review and meta-analysis of pregnancy, delivery, fetal and pelvic floor outcomes and call to action. British Journal of Sports Medicine. 2025;59(16):1173. doi:10.1136/bjsports-2024-109123
- Giles C, Johnston R, Kubler J, Spathis J and Beetham K. The effects of aerobic and resistance exercise on blood pressure in uncomplicated and at risk pregnancies: a systematic review and meta-analysis. Women’s Health. 2023. doi:10.1177/17455057231183573
- American College of Obstetricians and Gynecologists. Physical Activity and Exercise During Pregnancy and the Postpartum Period. Committee Opinion No. 804. 2020 (reaffirmed 2022).
- Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG). Exercise During Pregnancy. March 2023.