Strength Training During Pregnancy: How to Keep Training Safely

Pregnancy can suddenly make exercise feel much more complicated.

Exercises you've performed for years can start to raise questions. Can I still lift weights? Should I be using lighter weights? Can I train my core? Is this exercise still safe? Would it be better to stop strength training altogether?

For most women with an uncomplicated pregnancy, becoming pregnant doesn't mean you need to stop exercising or abandon strength training. Current guidance encourages women with uncomplicated pregnancies to participate in both aerobic and strength-conditioning exercise, although training will often need to be modified as pregnancy progresses. ACOG

The important distinction is this: pregnancy doesn't necessarily mean you need to stop strength training. It means your training needs to adapt.

Why Strength Training Still Matters During Pregnancy

During pregnancy, your body is dealing with increasing physical demands. Your body mass and centre of gravity change, everyday movements can begin to feel different, and tasks you previously didn't think twice about may gradually require more effort.

Maintaining your strength can help you remain physically capable throughout those changes.

The research into resistance training during pregnancy is also increasingly encouraging. A 2025 systematic review and meta-analysis included 50 studies and more than 47,000 participants. Resistance training, either alone or as part of a wider exercise programme, was associated with lower odds of gestational hypertension, gestational diabetes, perinatal mood disorders and having a baby with macrosomia compared with control groups. 

However, because most programmes combined resistance and aerobic exercise, the researchers cautioned that we can't confidently attribute all of those benefits specifically to resistance training. British Journal of Sports Medicine

Another 2025 systematic review of nine randomised trials found promising effects of strength training on areas including muscular strength, back and sciatic pain, mood and several measures of quality of life, although the authors also highlighted limitations in the available research. PubMed

You Can Still Challenge Your Body During Pregnancy 

Pregnancy naturally requires additional consideration, but that doesn't mean exercise has to become extremely gentle or that meaningful strength training needs to stop. 

For women with uncomplicated pregnancies, physical activity is considered safe and desirable. ACOG recommends that women who were already regularly active before pregnancy should generally be encouraged to continue, with modifications where necessary. ACOG

The NHS similarly advises continuing your normal physical activity or exercise for as long as it remains comfortable. nhs.uk

What is appropriate, however, will vary enormously.

Someone who has been strength training consistently for five years is starting pregnancy from a very different place from someone who has never lifted a weight before. Your previous training experience, current fitness, stage of pregnancy, symptoms and medical circumstances all matter.

Your Training Should Change as Your Body Changes

A good pregnancy strength programme shouldn't simply take your pre-pregnancy routine and make every weight lighter.

Instead, your training can evolve as your body does.

During the first trimester, the exercises themselves may not need to change dramatically for someone who was already training, but nausea, fatigue and changes in energy can affect what feels realistic.

As pregnancy progresses and your bump grows, exercises that were previously comfortable may become awkward. Your balance and centre of gravity change, and different positions or ranges of motion may need to be adjusted.

Later in pregnancy, further modifications may be necessary depending on comfort, stability and how you are responding to exercise.

That isn't a sign that you're losing fitness or "going backwards". The goal of training has simply changed.

Rather than judging progress solely by how much weight you're lifting, progress might mean maintaining your strength, moving confidently, adapting an exercise successfully or simply continuing to train consistently as your body changes.

Do You Need to Lift Lighter Weights?

Not automatically.

If you already strength train, you may be able to continue performing many familiar exercises during an uncomplicated pregnancy. But this isn't necessarily the time to aggressively increase your maximum lifts or repeatedly push yourself to exhaustion.

The appropriate load should take into account your previous experience, technique, the exercise you're performing, how you feel and how your pregnancy is progressing.

The NHS uses a useful general principle for exercise intensity during pregnancy: you should still be able to hold a conversation while exercising. If you're becoming too breathless to talk, you may be working too strenuously. nhs.uk

Rather than asking "How heavy am I allowed to lift?", a better question is often "Is this still an appropriate challenge for me today?"

What About Core Training?

Your core doesn't suddenly switch off because you're pregnant. In fact, the muscles around your trunk continue to play an important role as your body changes.

But core training may need to look different.

As your abdomen grows, some exercises and positions will become less comfortable or appropriate. That doesn't mean all abdominal exercise needs to disappear. It means choosing exercises that suit the individual and adapting them as pregnancy progresses.

Pelvic-floor training is also recommended during pregnancy. NHS guidance encourages pregnant women to perform pelvic-floor exercises because these muscles are placed under increased strain during pregnancy and childbirth. South West London Healthier Together

If you're experiencing symptoms such as pelvic pain, pelvic heaviness, leaking or other pelvic-floor concerns, this is also an area where individual assessment from an appropriate healthcare professional or pelvic-health physiotherapist can be valuable.

Some Exercises Will Need to Change

There isn't a neat list of strength exercises that becomes universally "banned" the moment you're pregnant.

But there are some important considerations.

The NHS advises against spending prolonged periods exercising flat on your back, particularly after 16 weeks, because the weight of the uterus can compress a major blood vessel and make you feel faint. Activities carrying a significant risk of falling or abdominal impact also require particular caution, and overheating and dehydration should be avoided. nhs.uk

Beyond those general precautions, modifications are often much more individual.

A growing bump might make a particular stance uncomfortable. Balance changes might make a supported version of an exercise more appropriate. An exercise that felt great several weeks ago might suddenly stop feeling right.

Good programming responds to those changes rather than trying to force your body to train exactly as it did before pregnancy.

What If You've Never Strength Trained Before?

You don't necessarily have to have been lifting weights before pregnancy to benefit from becoming more active.

But pregnancy isn't the time to suddenly jump from doing very little exercise to an aggressive training programme.

The NHS advises women who weren't previously active not to suddenly begin strenuous exercise. Instead, activity should be introduced gradually. nhs.uk

For a beginner, that might mean learning basic movement patterns, using manageable resistance and gradually developing strength and confidence under appropriate guidance.

The objective isn't to catch up with somebody who was already training before pregnancy. Your starting point is your own.

Know When to Modify or Stop Exercise 

Feeling challenged during exercise and experiencing a warning symptom are not the same thing.

ACOG advises stopping exercise and seeking medical advice if symptoms including vaginal bleeding, dizziness, headache, chest pain, painful regular contractions, amniotic fluid leakage, calf pain or swelling, or unusual shortness of breath occur. ACOG

And medical or obstetric complications can change whether exercise is appropriate at all, which is why individual advice from your maternity team takes precedence over general exercise guidance.

This isn't about being frightened of exercise. It's about recognising that good training includes knowing when not to push through something.

Train for the Body You Have Today

Pregnancy can change enormously from one week to the next.

An exercise that feels completely comfortable today may need adjusting several weeks from now. The amount you can comfortably lift may change. Your energy may fluctuate. Your priorities within your programme may shift.

None of that means your training is going backwards. The aim isn't necessarily to train exactly as you did before pregnancy, but to adapt your training to support your body as it changes. You can still challenge yourself, build confidence and maintain your strength, just in a way that feels appropriate for you at each stage. 

Good pregnancy training sits somewhere in between: continue to challenge your body appropriately, pay attention to how it responds and adapt your training as it changes.

Strength training during pregnancy isn't about maintaining your old programme at all costs. t's about maintaining your strength, confidence and physical capability through one of the biggest periods of change your body will experience.