March 03, 2016

2 Things You Didn’t Know About Pregnancy Exercise by Colleen Flaherty, CSCS

By MostFit Ambassador Colleen Flaherty, CSCS

When women get pregnant, my dream is that they instantly think, “well, it’s time to start preparing.”

We forget, we push it out of our mind, or we’re delusional to the fact that at the end of pregnancy, a baby has to be born by force. Crazy force! It’s called ‘labor’ because it’s hard work and for the past 75 years it’s been swept under the rug by epidurals and c-sections. 

Just like a warrior preparing for battle and an athlete preparing for the Olympics, labor is the pregnant woman’s main event. She has 9-ish months to mentally and physically prepare to bring life into this world. She takes responsibility for her and her baby’s health into her own hands. 

As trainers and coaches, it’s our duty to lead women down the road of health, joy, and body love. Too often I hear of coaches who fear training pregnant women because they don’t know how to modify movements. This exacerbates society’s already backwards view that a pregnant body is a fragile body.

Quite the contrary. 

For millions of years, humans have been hunters and gatherers ‘roughing it’ in the wilderness. Female anatomy has adapted to be protective, extremely efficient, and robust. In no way is a pregnant body fragile. It has more mechanisms to protect the fetus and the mother than anything we could ever duplicate with modern technology.  The research exists to show us the lower and upper limits of maternal exercise. 

1) Women can work up to 80% of the max heart rate during pregnancy.

That’s a lot. Sprinting. But most women will never reach that. During pregnancy, with more fluid coursing through more veins and arteries, women get out of breath a lot sooner. They also have a lower heart rate, which protects them from training in those upper levels of cardiovascular work. Running sprint work is great in the 1st and 2nd trimesters (if she feels well enough to do it), rope sprint work in the 3rd is just as effective. Caution: pregnant women should not be sprinting daily, just like any other person. It’s unnecessary and should be done 1-2 times per week within excellent programming to avoid burn out or over-training.

2) Women can continue to lift heavy through pregnancy with modifications and substitutions made for certain movements.

With the hormone Relaxin flowing through their bodies, most women become ‘looser’ in their joints. Light-weight, mobility, and pre-hab work comes in handy to help these smaller muscles stay strong to create stability. Movements like barbell back squats, snatches, and from the ground cleans put the back at increased risk of hypermobility in the later weeks. These can EASILY be modified with lower weight to work on conditioning, pulling from the hang position, and work on movement patterns. You can also substitute the barbell for dumb bells or kettle bells to work on stability and conditioning. 

No matter what, women aren’t going for PRs, they’re going for health. Help your clients realize that by first realizing it yourself. As a coach, sometimes it can be hard to slow a client down or know exactly when to encourage more. The greatest tip I can give you, is to consistently ask questions. Throughout the workout, if they are feeling sluggish/tired/out of it, challenge her differently (like dumb bell substitution) instead of adding more weight to the bar. On the other hand, if a pregnant member is going all out, and she has the athleticism to, be the coach that reminds her that modifications need to be made to allow a challenge that adapts with her changing body.  

And at the end of the day, if you don’t know what to do, download The Pregnancy Functional Strength Guide or attend a Pregnancy Strength CEU Course to learn how to keep this increasing population safe.



Paisley TS, Joy EA, Price RJ: Exercise During Pregnancy:                                                                                   A Practical Approach.                                                                                                Current Sports Medicine Reports 2003, 2:325–330 Current Science Inc. ISSN 1537-890x. 


Clapp JF III, Capeless E: The V02 max of recreational athletes
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