Posted: 15/07/2013 at 17:12
I’m a women’s health physio and work with many pregnant and postnatal mums. Although there is no established upper level of safe exercise intensity in pregnancy, the advice is that regular exercisers before pregnancy should be able to engage in high intensity exercise programmes, such as jogging, with no adverse effect to mum or baby. However, during the first trimester it’s important to not increase your core temperature by more than two degrees - so your core temp should be no more than 39.2 degrees celsius. Making sure you’re well hydrated and avoiding exercise when it’s very hot like today will help.
Current guidelines state that women who have reached a high level of exercise fitness before pregnancy should be careful when engaging in higher levels of fitness activities during pregnancy. As your pregnancy progresses, you should also expect a reduction in your overall activity and fitness levels.
Your safe maximum heart rate whilst exercising will vary depending on your age – 135-150 beats per minute if you are between 20-29 years old, 130-145 beats per minute if you are between 30-39 years old, and 125-140 beats per minute if you are over 40 years. Most guidelines advocate an upper range of 60-90% of your maximal heart rate for women wishing to maintain fitness during pregnancy. With this in mind, it can be helpful to wear a heart rate monitor when exercising to keep an eye on your heart rate.
You should always check with your GP or Obstetrician whether it is safe for you to continue with your preferred exercise programme during pregnancy. Depending on how much you’re exercising, you may need to have check ups to monitor/ assess the growth of baby to assess the effect of your exercise programme. Your regimen may then need to be adjusted or discontinued if necessary.
Hope this helps.