What type of exercise is safe during pregnancy?

This is a very common question from both women who are active and fit pre-pregnancy and those who want to get fit during a pregnancy.  The first question you need to ask is whether it is safe for you to exercise during pregnancy?   This is something that you should discuss with your doctor prior to continuing or starting an exercise plan.  For more information on this, please see a previous post under “Pregnancy” entitled: Is it safe for me to exercise during pregnancy. Once you and your doctor have determined that exercise is safe for you, you need to re-evaulate your fitness regime and potentially modify it to make if safe for you and your developing baby.

Often, the second trimester is the easiest time to exercise as you’re past the fatigue, nausea and vomiting that most commonly comes in the first trimester and you’re not yet too uncomfortable.  Be careful, as your joints tend to become more lax during pregnancy due to hormonal changes. As your pregnancy progresses beyond about 16 weeks, you should avoid exercises that have you lying flat on your back.  Lying flat on your back can reduce the return of blood flow to your heart, making you feel dizzy or unwell.  It can also reduce the blood flow to your baby. Certain exercises can be modified to be performed on your side, or you can wedge something under your hip.

You should avoid exercises that may cause you to lose balance.  As you gain weight, your balance and centre of gravity will shift – be aware of the changes in your body and how it affects your performance and capacity to exercise.  For example, bicycle riding can become difficult as your abdominal girth increases.  You should also avoid contact sports where you may be hit or kicked in the abdomen, as this can potentially cause trauma to your baby. 

If you are just starting out in an exercise program, you should begin with about 15 minutes of exercise, 3 times per week, and slowly increase to approximately 30 minutes at a time, four times per week. Make sure you stay well hydrated before, during and after your exercise!

You should be able to have a conversation while you’re exercising (i.e. not overly intense). You should modify your target heart rate goal from pre-pregnancy.  A good resource for this is the Canadian Society for Exercise Physiology.  They recommend a target (exercise) heart rate of 140-155 beats per minute (bpm) in women less than age 20, 135-150 bpm for women ages 20-29, 130-145 bpm for women ages 30-39, and 125-140 bpm for women over the age of 40.  Again, you must keep in mind your general level of fitness and potential exercise restrictions given your individual context.

Finally, keep in mind that you should not aim to develop peak fitness during a pregnancy.  This is a time of significant change in your body, and your fitness goals must change to accommodate this.  At the same time, it is even more important to maintain your fitness and health, as this has a significant impact on you and your baby.  Stay tuned for future blog posts where I continue discussing fitness during pregnancy!