Safe Exercise During Pregnancy: Trimester by Trimester

Somewhere along the way, a myth took hold that pregnant people should put their feet up and avoid moving too much. The opposite is closer to the truth. For most healthy pregnancies, staying active is one of the kindest things you can do for your body, your mood, and your sleep. The trick is knowing what to adjust as your bump grows. Here is the trimester-by-trimester rundown.

First, the green light and the guardrails

The gist: if your pregnancy is healthy and your provider has not told you otherwise, exercise is generally safe and good for you. The goal is moderate, not maximal. A useful rule is the talk test: if you can hold a conversation while you move, you are at a good intensity.

Before you start or continue a routine, run it by your provider, especially if you have any complications. A few things are off the table for most people: contact sports, anything with a real fall risk (think skiing or horseback riding), scuba diving, and exercising in serious heat. Otherwise, you have plenty of room to move.

First trimester: keep your rhythm

If you already work out, you can usually keep going at a similar level, just listen to your energy. The big challenge this trimester is often nausea and exhaustion, so go easy on the days when your body has nothing extra to give. A short walk on a rough day still counts. If you are new to exercise, this is a lovely time to start slow with walking, swimming, or a prenatal class. No need to lie flat on your back for long workouts.

Second trimester: the sweet spot

For many people, this is when energy returns and the bump is not yet in the way. Enjoy it. Swimming feels amazing, prenatal yoga and Pilates build strength for labor, and brisk walks are easy to keep up. One adjustment: from now on, avoid exercises that have you lying flat on your back for long stretches, since that can press on a major vein. Sit, stand, or lie on your side instead.

Third trimester: gentle and steady

As you get bigger, your center of gravity shifts and your joints loosen, so balance and comfort take priority. Keep moving, but ease off intensity. Swimming and water aerobics are heaven for tired joints. Pelvic floor exercises and gentle stretching pay off for birth and recovery. If something feels like too much, it is. Slowing down now is wisdom, not weakness.

Good picks by trimester

Trimester	Great choices	Ease off on
First	Walking, swimming, light strength, prenatal classes	Anything that triggers nausea or dizziness
Second	Brisk walks, prenatal yoga, swimming, Pilates	Lying flat on your back, high fall risk
Third	Water aerobics, gentle stretching, pelvic floor work	High intensity, balance-heavy moves

A few comfort tips that help a lot

• Warm up and cool down. Loose joints appreciate the easing in and out.
• Drink plenty of water and do not overheat. Skip the hot studio.
• Wear a supportive bra and shoes that grip. Your balance is changing.
• Eat a little something beforehand so you do not get lightheaded.
• Add pelvic floor exercises. Your future postpartum self will thank you.

When to stop and call your provider

Stop exercising and contact your care team if you notice vaginal bleeding, fluid leaking, regular painful contractions, chest pain, severe shortness of breath, dizziness or feeling faint, calf pain or swelling, or a headache that will not budge. These are signs to pause and check in, not to push through. When in doubt, rest and call. If you think you may be having a medical emergency, contact your local emergency services right away.

For more on caring for yourself through these months, see our main pregnancy guide.

Medical disclaimer: This article is for general educational purposes only and is not medical advice. It does not replace care from a doctor, midwife, or other qualified professional. Always check with your own provider before starting or continuing an exercise routine in pregnancy. If you think you may be experiencing a medical emergency, contact your local emergency services right away.

Sources

• American College of Obstetricians and Gynecologists. “Exercise During Pregnancy.” 2024.
• NHS. “Exercise in Pregnancy.” 2023.
• Centers for Disease Control and Prevention. “Physical Activity for Pregnant or Postpartum Women.” 2024.