Regular movement is one of the most powerful things you can do for yourself during pregnancy. Women who exercise have shorter labours, lower rates of gestational diabetes, easier postpartum recoveries and better mental health throughout. The American College of Obstetricians and Gynecologists (ACOG) is unambiguous: in the absence of medical complications, every healthy pregnancy benefits from at least 150 minutes of moderate activity per week. Here is exactly what to do — and what to avoid — in each trimester.
Why Exercise Matters in Pregnancy
Active pregnancies are linked with:
- Lower risk of gestational diabetes and preeclampsia
- Less excessive weight gain (see our pregnancy weight gain guide →)
- Reduced back pain and pelvic discomfort
- Better sleep, energy and mood
- Shorter active labour and lower caesarean rates in some studies
- Faster postpartum recovery and pelvic-floor restoration
The talk test: "Moderate intensity" means you can carry on a conversation but cannot comfortably sing. If you can sing, push a little harder. If you cannot speak in full sentences, slow down.
Safe Exercises by Trimester
First Trimester (Weeks 1–13)
If you exercised before pregnancy, you can usually continue your routine — just listen to your energy. Many women feel exhausted and nauseous, so reducing intensity is fine. If you are starting fresh, ease in gently:
- Walking — 20 to 30 minutes daily, brisk pace
- Swimming and aqua aerobics — joint-friendly, cooling
- Light strength training — bodyweight or moderate weights
- Stationary cycling — safer than road cycling once balance shifts
- Prenatal yoga and Pilates — beginners welcome
Second Trimester (Weeks 14–27)
This is the golden window — energy returns and the bump is still manageable. Add:
- Modified strength training — focus on glutes, back and arms
- Prenatal Pilates — pelvic stability and posture work
- Swimming — many women swim further than ever
- Stationary bike — gentler on hips than walking on hard pavement
- Water aerobics — joint relief plus cardio
From week 16 onwards, avoid lying flat on your back for more than a few minutes — the uterus can compress the inferior vena cava and reduce blood flow. Use a wedge or lie on your left side.
Third Trimester (Weeks 28–40)
Growing belly, looser ligaments and shifting balance mean lower-impact, more supported movement:
- Walking — even 15-minute walks help labour readiness
- Water aerobics and swimming — buoyancy is bliss
- Pelvic-floor work and Kegels — daily, three sets of ten
- Birth-prep yoga — focus on hip openers and breathing
- Gentle stretching — round-ligament release, calf stretches for cramps
A Daily Pregnancy Routine: 5 Steps
A safe 15 to 20 minute routine you can do every day, in every trimester:
Warm-up walk
Start with 5 minutes of brisk walking — outside or in place. Aim for a pace where you can still hold a conversation but cannot sing.
10 supported squats
Hold a sturdy chair or wall, feet hip-width apart. Lower into a squat as if sitting back into a chair, keeping weight in your heels. Stand up slowly. Repeat 10 times.
10 cat-cow stretches
On hands and knees, inhale and arch your back gently (cow), exhale and round it (cat). Move slowly through 10 cycles to release lower-back tension.
10 Kegels
Squeeze the muscles you would use to stop the flow of urine, hold for 5 seconds, release for 5 seconds. Repeat 10 times. Build to 3 sets per day.
5 minutes of breathing
Sit comfortably. Inhale through the nose for 4 counts, exhale through pursed lips for 6 counts. Five minutes lowers cortisol and trains breath control for labour.
Exercises to Avoid in Pregnancy
- Lying flat on your back after week 16 — restricts blood flow
- Contact sports (football, basketball, hockey, judo) — abdominal trauma risk
- Hot yoga and hot Pilates — overheating risk to baby in T1
- Scuba diving — decompression risk to fetus
- Skiing, horse riding, gymnastics — fall risk
- High altitude exercise above 1,800 m if not acclimatised
- Traditional crunches and sit-ups after T1 — diastasis risk
- Heavy overhead lifting in T3 — pelvic-floor strain
- Holding your breath during exertion — drops fetal blood flow
Warning Signs to Stop Immediately
Stop exercising and call your provider if you experience: vaginal bleeding, fluid leaking from the vagina, regular contractions, sudden chest pain, dizziness or fainting, calf pain or swelling, severe headache, decreased fetal movement, or shortness of breath before exertion.
6 Beginner Prenatal Yoga Poses
🧘♀️ Safe in every trimester
- Cat-cow — releases the lower back
- Child's pose (knees wide to make room for the bump)
- Butterfly / bound angle — opens hips for labour
- Side-lying savasana — restful relaxation on the left side
- Modified squat — strengthens pelvic floor and glutes
- Supported bridge with a block — gentle glute and hamstring work
Choose a prenatal-specific class if you are new to yoga; the cues and modifications are designed for a pregnant body.
Continue reading: Second Trimester Guide → · Third Trimester Guide →
Frequently Asked Questions
How much exercise is safe in pregnancy?
ACOG recommends at least 150 minutes of moderate-intensity activity per week — roughly 30 minutes on five days. Both lower and slightly more is fine if you are conditioned.
Can I keep running while pregnant?
If you were a regular runner before pregnancy, most providers will let you continue at a reduced intensity for as long as it feels comfortable — often into the second or third trimester. Listen to pelvic pressure and stop if you feel pain.
Are abdominal exercises safe during pregnancy?
Avoid traditional crunches and sit-ups after the first trimester to prevent diastasis recti. Safe alternatives include side planks, standing core work, pelvic tilts and breathing-based deep-core exercises.
When should I start prenatal yoga?
You can start in any trimester. Many studios accept beginners from the second trimester onwards. If you are new to yoga, choose a prenatal-specific class rather than a regular class.
Can I lift weights during pregnancy?
Yes, with adjustments. Reduce loads to roughly 50 to 70 percent of pre-pregnancy weight, avoid heavy overhead pressing in the third trimester, breathe out on exertion (no breath-holding), and stop any move that hurts.
Is it too late to start exercising in the third trimester?
It is never too late. Walking, swimming, prenatal yoga and pelvic-floor work are all safe to begin in the third trimester and can shorten labour, ease back pain and improve sleep.