Yes, working out during pregnancy is safe and actively encouraged for most women. The American College of Obstetricians and Gynecologists (ACOG) is clear on this: physical activity during pregnancy is both safe and desirable when there are no medical complications. The goal is at least 150 minutes of moderate-intensity aerobic activity per week, which breaks down to about 20 to 30 minutes on most days.
If you were active before getting pregnant, you can generally keep doing the same workouts. If you weren’t, pregnancy is actually a good time to start, building up gradually toward that 150-minute weekly target.
Why Exercise During Pregnancy Matters
Staying active during pregnancy does more than maintain fitness. It meaningfully reduces the risk of two serious pregnancy complications: gestational diabetes and preeclampsia (dangerously high blood pressure). One large-scale analysis published in the American Journal of Obstetrics & Gynecology estimated that exercise could prevent roughly 110,000 cases of gestational diabetes and nearly 75,000 cases of preeclampsia per million women. The same analysis linked exercise to fewer preterm births.
Beyond those numbers, regular physical activity helps manage back pain, reduces constipation, improves sleep, and supports a smoother postpartum recovery. Strength and cardiovascular fitness also help your body handle the physical demands of labor itself.
Safe Activities and What to Skip
Walking, swimming, stationary cycling, prenatal yoga, and low-impact aerobics are all solid choices. Strength training is also safe. A University of Alberta study specifically tested pregnant women performing barbell squats, bench presses, and deadlifts at increasing intensities and confirmed the safety of high-intensity resistance training during pregnancy. The study also found that the Valsalva maneuver, a breathing technique used when lifting heavy weights, was safe despite being traditionally discouraged during pregnancy.
Activities to avoid are those with a high risk of falling, abdominal trauma, or overheating:
- Contact sports like soccer, basketball, and hockey
- High-fall-risk activities like skiing, horseback riding, and gymnastics
- Scuba diving, which can expose the baby to dangerous pressure changes
- Hot yoga or exercising in extreme heat, since your core body temperature should stay below 102°F
- Skydiving and similar high-altitude activities
The Old Heart Rate Rule Is Outdated
You may have heard that pregnant women should keep their heart rate under 140 beats per minute. That guideline was retired decades ago. Current recommendations focus on perceived effort instead. The simplest tool is the “talk test”: if you can carry on a conversation during your workout, you’re at an appropriate intensity. If you’re too breathless to talk, ease up. This approach is more reliable than a heart rate number because resting heart rate naturally rises during pregnancy, making a fixed cutoff misleading.
Adjustments by Trimester
First trimester workouts can look a lot like your pre-pregnancy routine, though nausea and fatigue may require flexibility with scheduling and intensity. The biggest modification comes around 20 weeks, when lying flat on your back for exercise becomes a concern. At that point, the weight of your uterus can compress a major blood vessel (the inferior vena cava) against your spine, reducing blood flow back to your heart. This can cause dizziness, lightheadedness, or nausea. Swap flat bench exercises for inclined versions, and skip supine floor exercises like traditional crunches.
In the third trimester, your center of gravity shifts forward, balance becomes less reliable, and joints loosen due to hormonal changes. This is a good time to favor machines over free weights if balance is an issue, and to reduce high-impact movements like jumping or quick direction changes.
Protecting Your Core and Pelvic Floor
During pregnancy, the two halves of your abdominal muscles gradually separate to make room for the growing uterus. This is called diastasis recti, and certain exercises can make it worse. After about 12 weeks of pregnancy, avoid crunches, sit-ups, full planks, push-ups without modifications, and any movement that causes your belly to bulge or “cone” outward along the midline.
Instead, focus on deep core engagement. Exercises that use slow, controlled movements and deep breathing are ideal for strengthening the deep abdominal muscles without straining the separation. Good posture matters too: stand tall with your shoulders back, and breathe so your ribs expand rather than just your belly pushing forward. When getting out of bed, roll to your side first and push up with your arms rather than sitting straight up, which puts direct pressure on the abdominal wall.
Pelvic floor exercises (Kegels) are worth incorporating throughout pregnancy. These muscles support the bladder, uterus, and bowel, and strengthening them can reduce urinary incontinence during and after pregnancy.
Hydration and Overheating
Your body runs warmer during pregnancy, which makes overheating a real concern during exercise. Keep your core temperature below 102°F. In practical terms, this means avoiding outdoor workouts in high heat, wearing breathable clothing, and drinking plenty of water. The baseline recommendation during pregnancy is at least 64 ounces of water daily, and you should increase that on days you exercise or spend time in warm weather. If you feel overheated, dizzy, or faint, stop immediately and cool down.
When Exercise Isn’t Safe
There are a small number of conditions where exercise during pregnancy is not recommended. These include placenta previa (where the placenta covers the cervix), a cervical cerclage (a stitch holding the cervix closed), preeclampsia or pregnancy-induced high blood pressure, certain types of heart or lung disease, and being pregnant with multiples when there’s a risk of preterm labor. If you have any of these conditions, your provider will let you know.
ACOG notes that very few conditions are absolute contraindications. For most pregnant women, the benefits of exercise far outweigh the risks of staying sedentary.
Warning Signs to Stop Exercising
During any workout, stop and contact your provider if you experience vaginal bleeding, fluid leaking from the vagina, dizziness or feeling faint, chest pain, calf pain or swelling, headache that won’t go away, or regular painful contractions. Shortness of breath before you even start exercising (not just during) is also a red flag. These symptoms don’t necessarily mean something is wrong, but they need evaluation before you continue your routine.