The newest guidelines from the American College of Obstetricians and Gynecologists (ACOG) suggest a pregnant woman should use her rate of perceived exertion (see chart below) or the talk test to monitor effort level while exercising. A pregnant woman’s heart rate fluctuates throughout gestation, therefore making it difficult for you to determine from a number on a heart rate monitor just how hard your body is actually working. This is why rate of perceived exertion and the talk test can be more effective.
In 1985, ACOG conducted a study that resulted in their recommendation of 140 beats per minute as the maximum heart rate for a pregnant woman who is exercising. In 1996, the ACOG rescinded this guideline. Currently, research still recommends not exceeding the 140 BPM, as seen on the Borg Scale below. Please note that you should always follow your doctor’s protocol.
As mentioned above, in April 2020, ACOG determined that perceived exertion is a more effective way to monitor intensity than heart rate monitors. The talk test is another fantastic way to measure exercise intensity during pregnancy! Fun note: If you have are an avid exerciser, you might recognize you are pregnant because your normal routine has your RPE or heart rate going higher than usual.
A handful of research articles including the IOC’s Exercise and Pregnancy in Recreational and Elite Athletes suggest pregnant athletes should use a heart rate monitor as an additional tool because athletes tend to “push” through.
ACOG recommends the 15-point scale, while other research recommends a 10-point scale. For moderate intensity exercise you should be between 12 – 14 or “somewhat hard” on the Borg scale.
Measuring exertion through the talk test is one of the easiest ways to determine what’s too much and what’s too little. As long as you can carry on a conversation while exercising you are likely in the sweet spot and not overexerting yourself.
Please see the pregnancy exercise guidelines before beginning prenatal exercise. Read up on exercise during the first trimester and running during pregnancy.
Looking for workouts designed specifically for pregnancy? We’ve got tons of them in the Moms Into Fitness Studio.