Exercise and Pregnancy

12 Oct 15 - 09:48 AM

Many women are unsure whether to continue their exercise routine once they fall pregnant and even if they do are unaware of how much or how hard they should be training.

Many women are unsure whether to continue their exercise routine once they fall pregnant and even if they do are unaware of how much or how hard they should be training.

The first thing to understand is that your body is changing, with many anatomical, physiological and even emotional changes taking place over what is a relatively short time period. Obviously there is some weight gain on average around 10-15kg associated with pregnancy and with this weight comes an altered posture or body shape in general, there is more weight being carried at the anterior (front) of the body and an increase in the spinal curves with an increase in the lumbar (lower back) lordosis. This weight/shape change can alter how exercises which were performed prior to pregnancy are performed now, with changes to coordination, balance and may even cause some discomfort especially in the lower back as it has increased its weight bearing.

Levels of the hormone Relaxin increase during pregnancy, Relaxin is known to mediate the hemodynamic (blood and cardiovascular system) changes that occur during pregnancy, such as increased cardiac output, increased renal blood flow, and increased arterial compliance. It also relaxes other pelvic ligaments and is believed to soften the pubic symphysis. In regards to the loosening of ligaments this may place an individual at an increased risk of injury especially if the activity involves a lot of jumping, rapid changes in direction, and excessive stretching, also ballistic (explosive/elastic) type movements of the lower limb should be avoided during pregnancy as there is alot of strain placed on the pelvis. Lower back, pelvic and hip strengthening can all be achieved with low impact, well controlled resistance exercise and can improve your chances of staying injury free during pregnancy as it can help replace some of that stability lost with ligament laxity.


Whilst pregnant the amount of blood in our system increases as you are also providing blood for your little passenger, normally we see an increase in the resting heart rate and a decrease in the maximal heart rate during pregnancy. As stated before there are a lot of changes to blood flow and cardiovascular function during pregnancy, so if you were using target heart rates prior to pregnancy you need to change this measure of exertion. You want to maintain a steady heart rate and should do the talk test throughout your workout to make sure you are at a safe level (The talk test is when you talk during your workout).  If you are having a hard time talking and wind up huffing and puffing more than getting out actual words, then you are working too hard and need to decrease the intensity. Decrease in blood pressure is also seen during the 2nd trimester as more blood is being provided to the placenta, at around the 4 month stage rapid changes of position should be avoided as well as leg exercises whilst lying on your back.

Some handy tips

  • It is now considered safe to start an exercise program during pregnancy but note should be taken this is no time to be engaging in vigorous exercise routines and aiming to affect massive changes to body shape and fitness levels. Moderate exercise as determined by the BORG perceived exertion scale is considered safe.
  • Exercise in a well air conditioned environment especially in summer is very important, with some animal studies showing an increase in neural tube defects in relation to overheating in the first trimester.
  • By the 3rd trimester no more than 3 sessions per week
  • After the delivery gentle strengthening exercises can be commenced when it is comfortable to do so.
It is essential that you discuss exercise during pregnancy with your GP or exercise physiologist, as underlying conditions can affect how your body responds to exercise and in some cases exercise is contraindicated during pregnancy. Any abnormal symptoms during exercise such as headaches, dizziness, bleeding, uterine contractions, back or pelvic pain should be assessed and discussed with a healthcare professional before any continuation of the exercise program.

For more information on exercise during pregnancy don't hesitate to contact us at Synergy Healthcare on 9522 2125 or our website, where our multidisciplinary team can provide more in depth knowledge on an appropriate exercise program for your pregnancy.




Exercise and Pregnancy