As I stated in my first blog, I personally found it difficult to find good reliable information on exercising and pregnancy.   I read numerous books and found the most reliable one as mentioned before, was Exercising Through Your Pregnancy by Dr. James Clapp. The other reference that I will be referring to often in this blog is The American Congress (formally College) of Obstetricians and Gynecology as they are recognized as the expert resource for pregnancies. They have their own published recommendations for exercising while pregnant which you can find as a separate tab on this blog. I will generally defer to the ACOG recommendations as most OBGYN’s will use this organization as a resource but still feel that some of their recommendations might not fit every pregnant women. I believe that the ACOG errs on the side of caution and believe they should as they are putting out general statements and not able to advise every pregnant person. Their recommendations are based on years of research.

With that being said, even the ACOG has changed their position on some of their recommendations in 1994 and again in 2002. Unfortunately, some OBGYN’s are not familiar with their new recommendations and either still have their old recommendations printed in posters or brochures at their office or clients have told me that their doctor told them an ACOG recommendation from nearly 20 years ago!

I want to discuss a few of the most common myths of exercising and pregnancy. In my next post I will get into more detail about specific recommendations.

“Keep your heart rate below 140 bpm”

This is my favorite ‘myth’ as I think it is the most common rule of pre-natal exercise that most women have heard. However, this used to be a recommendation in 1985 when the ACOG published their first exercise during pregnancy guidelines. Most of the early studies that these recommendations were based off of were performed on animals.

In 1994, the guidelines were revised and the 140 bpm limit was removed but no other specific heart rate guidelines were given mainly because no doctor or researcher wants to test on pregnant individuals (nor am I assuming many pregnant women would volunteer for a test to see what HR is safe). However, Dr. Clapp does state that “Heart rate is not a good predictor of how hard a women in working during pregnancy and therefore not a reliable measure of safely, health or fitness. Rate of perceived exertion may be a much better index.”

Just as with a non-pregnant person, HR cannot always quantify everything that is going on during a workout. HR can fluctuate based on training levels, hydration, recovery from previous workouts, sleep quality, medication, age and more. Therefore a 25-year old active pregnant person can have a very different heart rate than a sedentary 35-year old pregnant woman. Even genetics can create a 15-30 beat per minute difference while exercising at a moderate intensity. Giving women one specific heart rate to stay under did not make sense.

Once again in 2002 the guidelines were revised adding the recommendations that pregnant women (with the exception of contraindications) should get 30 minutes of moderate intensity exercise most if not all days of the week! This is similar to the recommendations made by the Centers of Disease Control for all individuals showing that exercise is highly recommended during pregnancy.

“Exercising can hurt the baby”

This is a very valid fear. Even I had concerns when I was pregnant. How much exercise is too much? How high can my HR get?   Does the baby get jostled when I run?   Though there are certain types of exercises that are not recommended while pregnant (scuba diving, exercises that pose a risk to falling, i.e. horseback riding, skiing) if you have any questions about your type of exercise, PLEASE consult your OBGYN.

Dr. Clapp’s research he found the following:

“Continuing regular, vigorous exercise throughout early pregnancy does not increase the incidence of either miscarriage or birth defects or the incidence of either membrane rupture or preterm labor.” He found that the incidence of miscarriage was the same rate for exercisers and non-exercisers. He also found that “exercise habits are unrelated to ectopic pregnancy.”

The human body is an amazing thing. Even though it might feel that your baby is being ‘jostled’ when running, your womb is protecting the baby. Yes, you might have to modify your routine but it is safe for you to run.

“You should not lift weights, especially heavy weights during pregnancy”

Though I believe in listening to your body, getting plenty of rest, eating nutritious food (these are actually good recommendations if you are pregnant or not 🙂 ) I do not think pregnant women are as fragile as society sometimes perceives them to be. Of course, I think you should make safe and smart choices when expecting but that does not mean you have to lift 3lb weights because you are pregnant. I am also not advocating going for a PR on your power clean or bench press, you just might not need to modify as much as you might think.

Strength training should be a part of any well-rounded exercise program.   Fortunately, the popularity of weight lifting has continued to grow for both men and woman of all ages. Weight lifting has so many benefits for any individual including pregnant women.

Resistance Training During Pregnancy: Safe and Effective Program Design, published in the National Strength and Conditioning Association Journal is an excellent article covering many aspects of weight lifting while expecting (Check out the article here:

Brad Schoenfeld recommends that weight lifting sets for pregnant women should be somewhat challenging but should not push to absolute muscular fatigue. (Again, more specifics to be posted later)

The author also states that “in the absence of any complication or contraindication, there appears to be no reason that in most cases training cannot continue until immediately before delivery.” So lift on ladies!

What other myths have you heard about exercising and pregnancy? I would love to hear from you!