Regular physical activity during pregnancy has moved from "permissible" to explicitly recommended by every major obstetric body (ACOG 2020, WHO 2020, NICE, RCOG). The evidence is consistent: women who exercise regularly during pregnancy have lower rates of gestational diabetes, pre-eclampsia, excessive weight gain, caesarean section, depression, and back pain, and their babies have better neurodevelopmental outcomes. Despite this, surveys suggest fewer than 25% of pregnant women meet current activity guidelines. This guide explains what's safe, what to avoid, and how to adapt your routine across the three trimesters.

150 minutes of moderate-intensity aerobic activity per week, spread across most days, plus muscle-strengthening activity 2 days/week. This matches the recommendation for non-pregnant adults. If you were already doing more (e.g. 300 min/week or vigorous activity), you can generally continue, though you may need to adapt intensity and movements as pregnancy progresses.

Moderate intensity = you can talk but not sing comfortably. Heart rate 60–80% of maximum, typical range 120–140 bpm depending on age and fitness.

| Outcome | Effect of exercise |

|---|---|

| Gestational diabetes | ~30% lower risk |

| Gestational hypertension / pre-eclampsia | ~35% lower risk |

| Excessive gestational weight gain | 1–3 kg less on average |

| Caesarean section | ~15–20% lower rate |

| Lumbopelvic pain | Significantly reduced |

| Depression/anxiety | Lower incidence antenatal and postnatal |

| Labour duration | Shorter first stage in active women |

| Postpartum recovery | Faster; less pelvic-floor dysfunction |

| Infant neurodevelopment | Improved motor development at 1 year |

- Haemodynamically significant heart disease

- Restrictive lung disease

- Incompetent cervix or cerclage

- Multiple gestation with high risk of preterm labour

- Persistent second- or third-trimester bleeding

- Placenta praevia after 26 weeks

- Premature labour in current pregnancy

- Ruptured membranes

- Pre-eclampsia / pregnancy-induced hypertension

- Severe anaemia

Relative contraindications (exercise with caution, with obstetrician clearance): anaemia, unevaluated cardiac arrhythmia, chronic bronchitis, poorly controlled type 1 diabetes, extreme obesity (BMI >40) or extreme underweight (BMI <12), intrauterine growth restriction, poorly controlled hypertension, orthopaedic limitations, poorly controlled seizure disorder, poorly controlled hyperthyroidism, heavy smoker.

- Contact sports: boxing, rugby, football, basketball, ice hockey — risk of abdominal trauma

- High-fall-risk sports: downhill skiing, horseback riding, surfing, off-road cycling, gymnastics — risk of falls and abdominal trauma

- Scuba diving — risk of decompression sickness in the fetus

- Hot yoga / hot Pilates (Bikram) — overheating risk

- Skydiving

- Altitude >2500 m if you're not acclimatised (visiting the mountains at altitudes above this is generally discouraged after first trimester)

- Activities involving supine exercise after the first trimester (uterine compression of inferior vena cava → reduced cardiac output and uteroplacental perfusion). Modify by tilting left or using a wedge pillow.

The body is changing rapidly inside — you often feel little externally yet. Nausea, fatigue, and breast tenderness are the biggest exercise barriers.

What's great:

- Brisk walking — simplest, safest, accessible

- Swimming / aquafit — buoyancy helps if nauseous; whole-body workout

- Stationary cycling — no fall risk

- Light resistance training — keep weights at 60–70% of pre-pregnancy max, higher reps

- Prenatal yoga / Pilates — builds flexibility and core stability; avoid deep twists and inversions

- Jogging — OK to continue if you ran before pregnancy

Practical tips:

- Dress in layers — core temperature must stay <38.9°C (102°F). Avoid exercising in hot/humid conditions.

- Hydrate well: 500 mL 2 hours before, 250 mL every 15–20 min during

- Eat a small snack 30–60 min before exercise to prevent hypoglycaemia

- Do NOT start a brand-new intense regimen in first trimester — if previously sedentary, start with 15 min walking and progress slowly.

- Stop if you have bleeding, severe cramping, or dizziness.

Often called the "honeymoon" — energy returns, nausea resolves, belly growing but not yet limiting. Best window to establish a routine.

Modifications:

- No supine (flat on back) exercise after ~16 weeks — modify to tilted, side-lying, or standing

- Widening ligaments (relaxin) — avoid deep stretches, high-impact plyometrics, or unstable surfaces

- Core work: replace crunches with standing/kneeling core (bird-dog, pelvic tilts, side planks). Screen for diastasis recti — vertical gap along linea alba; avoid exercises that bulge the abdomen.

- Balance: centre of gravity shifts; reduce risk of falls by using stable surfaces

- Avoid activities that bounce on the pelvic floor excessively (heavy jumping)

Pelvic floor: start Kegel exercises early — 3 sets of 10 holds (10 seconds each) daily. Reduces urinary incontinence and supports perineal recovery after birth.

The belly limits many movements. Focus shifts from fitness gains to maintenance, preparing for labour, and pelvic-floor conditioning.

Great options:

- Walking (even 2×20 min/day improves outcomes)

- Swimming — removes weight from joints; great relief

- Stationary cycling (recumbent may be more comfortable)

- Prenatal yoga focusing on hip openers, breathing, pelvic stability

- Squats — improve pelvic mobility; many cultures use them as a birthing position

- Birth ball exercises — gentle hip circles, bouncing, figure-eights

What to stop:

- Running: only if comfortable; many women transition to walking by 32–34 weeks

- Heavy lifting: use lighter weights, more reps, better form

- Any exercise requiring lying flat

- Rapid direction changes (basketball-style pivots)

Round ligament pain (sharp pain in lower belly when changing position): reduce intensity, massage, warm compresses.

- Vaginal birth without complications: restart gentle walking and pelvic-floor exercises as soon as you feel ready (often day 1–2). Return to pre-pregnancy exercise gradually from 4–6 weeks, once bleeding has settled and provider confirms at postnatal check.

- Caesarean section: walk daily from discharge. No lifting >5–6 kg for 6 weeks. Resume aerobic and strength training gradually from 8–12 weeks.

- Perineal tear (3rd/4th degree) or episiotomy: avoid impact exercise until pain-free, usually 6–8 weeks.

- Pelvic-floor physiotherapy is standard of care in many countries; if you have persistent urinary leakage, faecal urgency, pelvic pressure, or pain, seek a specialist early.

- Return to running: check for pelvic-floor readiness at 12 weeks: single-leg hop test, no leakage, no heaviness. Postpartum-specific plans (e.g. Couch to 5K for Postnatal) are useful.

- Vaginal bleeding

- Leaking fluid (possible ruptured membranes)

- Regular painful contractions before 37 weeks

- Chest pain, shortness of breath before exertion

- Severe headache, visual changes

- Calf pain or swelling (DVT)

- Dizziness / syncope

- Muscle weakness affecting balance

- Reduced fetal movement after an episode of exercise

- Severe abdominal pain

| Day | Activity | Duration |

|---|---|---|

| Monday | Brisk walk + pelvic floor exercises | 30 min + 10 min |

| Tuesday | Prenatal yoga | 45 min |

| Wednesday | Swimming or aquafit | 30 min |

| Thursday | Strength training (resistance band, bodyweight) | 30 min |

| Friday | Walk or stationary bike | 30 min |

| Saturday | Longer walk / hike on level terrain | 60 min |

| Sunday | Stretching + rest | — |

Total: ~180 min aerobic + 30 min strength + stretching — exceeds 150-min minimum.

- "Exercise causes miscarriage." — False. Regular exercise does NOT increase miscarriage risk (multiple systematic reviews).

- "Heart rate must stay below 140 bpm." — Obsolete. Current guidance uses "talk test" or rate of perceived exertion (RPE) 12–14/20.

- "If you didn't exercise before, don't start now." — False. Start gradually at any time, even in late pregnancy.

- "Core work is dangerous." — False. Modified core work is beneficial — just avoid supine crunches after 16 weeks and exercises that bulge the abdomen.

- "Swimming causes infections." — False, in well-chlorinated public pools. Avoid hot tubs and hot baths.

- Twin pregnancy: low-to-moderate intensity only; avoid after 24 weeks unless cleared. Higher baseline risk of preterm labour.

- IVF pregnancy: no specific restriction; treat as any other pregnancy after early reassurance scan.

- Previous preterm birth: discuss with obstetrician; often limited to walking and gentle yoga.

- Gestational diabetes: exercise is part of treatment. Walking 10 min after each meal is particularly effective for glucose control.

- High altitude (>2500 m): for visiting, allow 4–5 days of acclimatisation; avoid exertion on arrival. Living permanently at altitude is generally fine.

Exercise increases calorie requirements by 300–500 kcal/day in pregnancy. Focus on protein (iron, zinc) and complex carbohydrates. Iron demand is already high in pregnancy — active women may need supplemental iron if stores are low. Ensure adequate folic acid, calcium (1000 mg), and vitamin D (600–2000 IU).

Unless you have a specific medical contraindication, staying physically active is one of the best things you can do for yourself and your baby during pregnancy. Aim for 150+ minutes of moderate activity per week, adapt intensity and positions as your body changes, hydrate well, avoid contact and high-fall sports, and know the warning signs to stop. When in doubt, ask your obstetrician — but the default is: keep moving, respectfully.

More information: iron, folic acid. For any new symptom during exercise in pregnancy, stop and contact your obstetrician.