According to Rachel Trotta, a NASM-certified personal trainer specializing in pre and post-natal fitness, the 140 BPM guideline is outdated.
That number was once chosen based on the belief that a pregnant mother raising her heart rate too high could impact the blood flow and oxygen levels provided to their baby.
While this recommendation may not be up to snuff, though, making an ideal heart rate recommendation is not easy either.
According to Amy Schultz, a physical therapist for the Fit Body app, “A blanket heart rate precaution is a bit tricky since everyone’s max heart rate is so different and can be different day to day.”
“Instead, knowing your own personal max heart rate and basing your training off a percentage of that would be more ideal. Also, going off of RPE is a great, research-backed way to stay active safely during pregnancy!”
RPE stands for “rate of perceived exertion,” which is used for more current exercise recommendations. So, rather than monitoring their heart rate, pregnant people can self-assess using what’s known as the “talk test.” We will discuss more of that later.
First, though, let’s answer the big question: Is it okay to participate in a high-intensity workout while pregnant? The honest answer is that it depends.
If you are an athlete or someone who regularly trained at high intensities before your pregnancy, you can continue doing so after conceiving as long as you modify workouts when necessary to account for your pregnancy progression.
“While research is lacking, people with low-risk pregnancies who previously performed high-intensity exercise may continue this level throughout their pregnancies,” underscored Stephanie Hack, MD, host of “Lady Parts Doctor Podcast” and a board-certified obstetrician and gynecologist.
“However, they should monitor for symptoms such as bleeding, abdominal pain, fluid leakage, regular painful contractions, etc.”