A British professional model kept exercising during her whole pregnant process, her belly right before birth only looking like a 15 weeks pregnant belly. Her fans worried about her intensity of exercising and her baby’s health, but it turned out her baby was healthier than most British newborns.
You may think that’s only because she was professional enough and healthy enough to keep intense exercising during pregnancy without influencing the baby, but the fact is vigorous exercise even during the third trimester of pregnancy is safe and healthy.
Exercise during pregnancy
The main aim of physical activity in pregnancy is to achieve health-enhancing benefits in a way that is safe, enjoyable, and sustainable. Regular exercise during pregnancy can improve our posture and decrease some common discomforts like backaches and fatigue. Physical activity may also prevent gestational diabetes.
Moderate exercise vs vigorous exercise
Walking, swimming and using an exercise bike are all activities classified under moderate exercise. Expectant mothers are recommended to do at least 150 minutes of moderate intensity physical activity per week.
Vigorous exercise refers to the intensity under which you can manage a sentence, but struggle to maintain a conversation. Jogging, circuit-based resistance training, and interval training on a stationary bike are some examples of vigorous exercise.
Your heart rate should reach 70% - 90% of your maximum heart rate, which is about 220 beats per minute minus your age. It may not be easy for you to achieve vigorous intensity exercise because of some normal changes to the heart and blood during pregnancy.
The safety of vigorous exercise during pregnancy
Researchers analyzed 15 studies looking at mothers exercising at a vigorous intensity during the third trimester to understand how safe is as for mothers and babies. Data of 32,703 pregnant women was included in the research.
The result shows that vigorous exercise appears to be safe for both mum and baby, even when continued into the third trimester.
No observed increased risk was presented in the result. No difference in birth weight of babies when their mums did vigorous exercise. No difference in the number of babies born small for gestational age.
For women in the healthy weight range, vigorous exercise didn’t affect the amount of weight they gained during pregnancy. They just followed the expected weight gain as their pregnancy progressed.
For overweight and obese women, however, vigorous exercise appeared to reduce maternal weight gain.
What you should do
Exercise, not only vigorous exercise, but basically any kind of moderate to vigorous exercise, is good for your health physically and psychologically during pregnancy.
Remember you should keep your heart rate less than 90% of your maximum heart rate (220 minus your age). High-intensity exercise (when your heart rate is beyond 90% of the maximum heart rate) can be potentially dangerous, and there is no such research proving it safety.
Mothers will usually get the most benefit with some extra support, whether from an exercise professional (like an accredited exercise physiologist), a medical practitioner, or both. Programs can be tailored to the most suitable exercise intensity for you.