Exercise in pregnancy is safe and promotes a sense of wellbeing. Women who exercise during pregnancy tend to have a shorter labour and fewer complications from the birth. Exercise in pregnancy should aim to keep you fit, rather than improve your physical fitness, or prepare you for a competition.
Stop exercising if you feel dizzy or faint, start having a headache, cannot catch your breath or develop pain or palpitations in your chest, abdomen, back, pubic area or pelvic girdle. Stop exercising if you start to feel weakness in your muscles, or start to have painful uterine contractions, fewer movements of the baby, leaking of fluid or bleeding from the vagina.
If you do not exercise routinely and are starting on an exercise program in pregnancy, begin your exercise program with no more than 15 minutes continuous exercise three times a week, increasing gradually to a maximum of 30 minutes sessions four times a week.
If you exercised regularly before pregnancy, you should be able to do the same exercise program with no adverse effects to you or the baby.
Exercise in pregnancy helps relieve tiredness, lower back pain, reduce varicose veins and swelling of the feet and ankles. Staying fit during pregnancy may help to reduce feelings of stress, anxiety and depression as well as help you sleep. It improves muscle tone strength and endurance. Exercise during pregnancy may help to prevent medical conditions such as diabetes and high blood pressure.
Swimming in pregnancy is safe. The water temperature should not exceed 32°C in a swimming pool and 35°C in a hydrotherapy pool, so that you do not get too hot.
Avoid contact sports such as kick-boxing, judo or squash during pregnancy because there is a risk of being hit in the abdomen.
You should avoid scuba-diving for your entire pregnancy, because the baby has no protection against decompression sickness and gas embolism under water.
Take extra care when doing exercise where there is a possibility of falling, such as horse riding and down-hill skiing. A serious fall may injure you and the baby.
- Getting too hot (hyperthermia)
When you exercise, your body temperature increases. If your body temperature rises above 39.2°C in the first 12 weeks, this may affect the baby’s development and may lead to disability at birth. To make sure that you do not get too hot, you should ensure that you drink lots of water before and during exercise, avoid over exerting yourself and exercising in a very hot and humid climate.
- Low blood pressure (hypotension)may also affect you and the pregnancy.
When you lie flat on your back, the growing baby presses on the main blood vessels to your heart. The effect is that less blood is pumped back to your heart and this may lead to low blood pressure. To reduce the risk of low blood pressure, you should avoid exercises that involve lying flat on your back, particularly after 16 weeks when your ‘bump’ is bigger.
- Injury to yourself or the baby
The pregnancy hormones make your joints looser. Make sure that you do the warm up and cool-down exercises, avoid sudden changes of direction and consider wearing a pubic support belt during exercise.
- Exercising at high altitude may result in insufficient oxygen
Make sure that you acclimatise for several days before exercising at altitudes over 2500 metres.
Blood sugar is a source of energy for you and the baby. It is important that you eat well during pregnancy and exercise no more than 45 minutes at a time. The general advice is that you should be able to hold a conversation while exercising. This is called the ‘talk test’.
Exercise is safe after the birth and does not affect breastfeeding.