Safe Exercises During Pregnancy: A Trimester-by-Trimester Guide
Quick answer
Most pregnant people can safely exercise — ACOG and the NHS recommend about 150 minutes of moderate activity per week, like brisk walking, swimming, or prenatal yoga. Get your own clinician's go-ahead first, especially if you have complications. Stop and call your provider for vaginal bleeding, dizziness, chest pain, or regular painful contractions.
Key takeaways
- In uncomplicated pregnancies, exercise is safe and recommended — not something to avoid out of caution.
- The target: ~150 minutes of moderate activity per week (the talk test: you can talk, but not sing) plus muscle strengthening twice a week.
- Best bets across all trimesters: walking, swimming, stationary cycling, prenatal yoga, and modified strength training.
- Avoid: contact sports, fall-risk activities, hot yoga, scuba diving, and lying flat on your back for long periods after the first trimester.
- Stop exercising and call your provider for any warning sign — the full list is below.
Is it safe to exercise while pregnant?
Yes — for most people with uncomplicated pregnancies. ACOG's committee opinion on physical activity in pregnancy states that in the absence of obstetric or medical complications, physical activity in pregnancy is safe and desirable. The NHS says the same: exercise is safe for you and your baby in pregnancy.
The documented benefits (per ACOG's review of the evidence) include a lower chance of excessive gestational weight gain, gestational diabetes, gestational hypertensive disorders, preterm birth, and cesarean birth — and a higher chance of vaginal delivery. The NHS adds better sleep, mood, and preparation for labor.
The one non-negotiable: talk to your own clinician first, especially if you have heart or lung disease, placenta previa, preeclampsia, a cerclage, multiples, anemia, or a history of preterm labor. Those situations call for individualized advice, not a general guide. For a broader safety overview, see our pregnancy-dos-and-donts.
Safe exercises by trimester
The table below shows what works well in each trimester and what to modify. The principle: keep doing what your body knows, and adjust as your balance, joints, and bump change.
| Exercise | First trimester | Second trimester | Third trimester |
|---|---|---|---|
| Brisk walking | Excellent — the default | Excellent | Excellent — shorter, comfortable sessions |
| Swimming / water aerobics | Excellent | Excellent — the water supports your weight | Excellent — often the most comfortable option |
| Stationary cycling | Great | Great — switch from road cycling to stationary as balance changes | Great — keep resistance moderate |
| Prenatal yoga / stretching | Great | Great — avoid deep twists and lying flat for long | Great — gentle, with props; skip hot yoga |
| Strength training (light–moderate) | Good — normal routine fine | Good — lighter weights, more reps; avoid lying flat on bench | Good — seated or standing moves; stop if joints feel unstable |
| Dancing / low-impact aerobics | Good | Good | Good — lower impact as balance shifts |
| Running | Continue if you were a runner | Many continue; cut back as comfort dictates | Usually walking replaces running — listen to your body |
| Pelvic floor exercises (Kegels) | Start or continue daily | Continue daily | Continue daily — helpful for labor recovery |
The "start here if you were inactive" plan: you don't need to become an athlete. ACOG's patient guidance suggests starting with 10–15 minutes of activity (walking is easiest), adding about 5 minutes per week until you reach 30 minutes on most days. Any activity beats none — the NHS is explicit that if you can't reach 150 minutes, doing what you can still counts.
Exercises and activities to avoid
Per ACOG, avoid activities that raise your risk of injury or overheating:
- Contact sports and anything with abdominal impact risk — ice hockey, boxing, soccer, basketball
- Fall-risk activities — downhill skiing, water skiing, surfing, off-road cycling, gymnastics, horseback riding
- Hot yoga / hot Pilates — overheating risk
- Scuba diving — pressure-change risk to the fetus
- High altitude above 6,000 feet if you don't already live at altitude
- Lying flat on your back for long periods after the first trimester (if you feel dizzy or lightheaded on your back, roll to your side — the weight of the uterus can press on the main blood vessel returning blood to your heart)
Note the pattern: it's not "don't move" — it's "don't get hit, don't fall, don't overheat."
How much exercise do you need?
The headline number, from both ACOG and the NHS: at least 150 minutes of moderate-intensity aerobic activity per week, spread across the week (for example, 30 minutes on 5 days), plus muscle-strengthening activities on 2 days.
What counts as "moderate"? The talk test: you can hold a conversation while moving, but you couldn't sing. Your heart rate is up, you're breathing faster, you feel warmer.
Practical ways to hit it:
- 30-minute brisk walk, 5 days a week (the simplest complete plan)
- 3 swim sessions of 40–50 minutes + 2 short strength sessions
- Daily 20–25 minute walks + a prenatal yoga class twice a week
- 10-minute walks after each meal, daily (great for blood sugar and digestion too)
If you were already vigorously active (running, intense training) before pregnancy and your pregnancy is uncomplicated, you can generally continue at a similar level with your clinician's awareness — pregnancy is for maintaining fitness, not for peak performance goals.
Warning signs: stop exercising and call your doctor
ACOG lists these as stop-and-call signs. Don't push through any of them:
- Vaginal bleeding
- Feeling dizzy or faint
- Shortness of breath before starting exercise
- Chest pain
- Headache
- Muscle weakness affecting your balance
- Calf pain or swelling
- Regular, painful contractions of the uterus
- Fluid leaking from the vagina
Save this list in your phone. For other "is this normal or a call-the-doctor moment" questions, our when-to-call-your-midwife-or-doctor-in-pregnancy guide covers the full picture.
Tips for exercising safely
- Hydrate before, during, and after. Drink water even for short sessions.
- Eat enough. A small snack 30–60 minutes before longer sessions prevents lightheadedness.
- Warm up and cool down. Five easy minutes on each end; skip abrupt stops.
- Dress for heat. Avoid exercising in hot, humid conditions; overheating is the enemy.
- Support matters. A good sports bra, supportive shoes, and (later on) a belly support band make everything more comfortable.
- Tell your instructor. If you take classes, make sure the teacher knows you're pregnant and how far along you are.
- Pelvic floor daily. Kegels take a minute, need no equipment, and pay off in labor recovery — ask your midwife for technique pointers if you're unsure.
Build in rest days too — two or three moderate sessions a week with recovery in between is a solid pattern for most people. And if you were very active before pregnancy, you can often continue with your provider's okay, adjusting intensity as your body changes.
Track your activity alongside the rest of your pregnancy in our pregnancy-checklist-by-trimester.
Sources
- Committee Opinion: Physical Activity and Exercise During Pregnancy and the Postpartum Period (safe exercises: walking, stationary cycling, aerobics, dancing, resistance, stretching, water aerobics; 20–30 min moderate exercise most days; stop-exercise warning signs)American College of Obstetricians and Gynecologistshttps://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2020/04/physical-activity-and-exercise-during-pregnancy-and-the-postpartum-periodLink checked 2026-10-16
- "The Top 6 Pregnancy Questions I Hear From First-Time Moms" (150 minutes per week; start at 10–15 minutes if inactive; activities to avoid including lying on back; caffeine guidance)American College of Obstetricians and Gynecologistshttps://www.acog.org/womens-health/experts-and-stories/the-latest/the-top-6-pregnancy-questions-i-hear-from-first-time-momsLink checked 2026-10-16
- Exercise in pregnancy (150 minutes of moderate-intensity activity per week including muscle strengthening; talk test; "any activity is better than none")NHShttps://www.nhs.uk/pregnancy/keeping-well/exercise/Link checked 2026-10-16