Pregnancy + The Athlete


Nausea, Fatigue, Intensity & Risk

“Take it easy, now, you’re pregnant!” It’s commonly heard advice, but just how seriously should this statement be taken and what exactly does that mean for the athletic female?

Hedge Fondo, 6 weeks

Ever since becoming pregnant, I’ve had interest in what limitations I might have for exercise, how exercise feels and what my experience has been so far. For someone whose social circles, career, favorite pastimes and sanity involve endurance exercise of some sort, there’s a natural fear of how drastically pregnancy may alter so much of your life. Will I still be able to join my friends and group rides and participate in my community? When much of my work integrates riding and travel, how will that be affected and what will that look like once parenthood arrives? What are the limits on what I can do and will my doctor understand my background or give recommendations that generalize for the average population? I’ve always been one to push back a bit on the “rules” and understand the why behind them, much to the impatience of my mother during my childhood. People are not one size fits all.  

Arming oneself with research—what little that actually exists— was the most important first step. The first book I picked up was Exercising Through Your Pregnancy by Dr. James Clapp which I devoured in one plane ride and proceeded to read multiple times through. 

It used to be advised, and unfortunately despite new and updated research is still often advised, that a pregnant woman should keep her heart rate below 140. For someone who thrives off a solid endurance sport induced sweat, I tried to imagine what it would look like to make it 9 months with this mandate in mind. No amount of yoga or strength training would be enough to stimulate the endorphin rush that I seek day in and day out.  

Turns out heart rate is not only extremely individual—some have hummingbird hearts and others pump bigger volumes of blood more slowly, but also highly variable based on genetics, fitness, age, hydration, fatigue and many other factors. New research has admitted, “there was never much evidence for the heart rate cap” and has moved along to new suggested protocol to measure one’s limits—the very official “monitor how you feel before, during and after exercise” as the best gauge for establishing limits. 

The human body actually undergoes some impressive adaptations to increase its efficiencies while pregnant. Progesterone rises and signals your brain to take deeper and faster breaths. Respiration increases by 40-50%. It’s commonly heard that women almost immediately feel more out of breath upon exercising. If the science behind this was not understood, it might lead one to believe that they’re already losing fitness or the intensity is too high, when in fact, it’s simply a superb adaptation by the body to optimize gas transfer between the mom and the baby. In addition to this, increased respiration improves the ability to get rid of body heat through expiration. 

Pregnancy reduces normal body temperature and reduces the temperature at which sweating happens—more sweat equals the ability to more efficiently dissipate body heat. Hormones increase blood vessel dilation which brings more blood flow to the skin and aids in allowing the body to dissipate heat through the skin. Since thermoregulation is one of the key concerns for intense exercise while pregnant, it’s advantageous that your body is creating more cooling efficiencies.

Crested Butte, CO, 10 weeks

I recently found myself pedaling up one of the toughest climbs near my house and though I had my power readout in front of me showing me strong numbers, I was breathing so hard that I was convinced I had never been so out of shape and slow up the climb. I was later surprised to see that my Strava results told me otherwise and that I had my fastest time ever, despite already being a few pounds heavier. That’s what increased respiration does—it can fool you into thinking you’re much more out of shape than you think! 

As far as intensity goes, I’m not out there doing sprint workouts, but I feel quite comfortable with intervals or short bits into the tempo, threshold and potentially VO2 categories (depending on length). That may change later in the pregnancy as it’s been said pregnancy in and of itself is akin to baseline training (as far as stress on the body) so there’s less in the tank for intensity during an actual workout or especially as the weight gain increases. I have found that short intervals of intensity still deliver the endorphin high that I look forward to and keep me feeling like myself. The nice thing about the bike is that after a short burst of intensity, there’s a chance to recover well to ensure optimal uterine blood flow. Additionally, see below chart for pregnancy optimizations affecting oxygenation. Studies have hypothesized that exercise increases the size and rate of growth of the placenta (the fascinating organ that facilitates gas transfer and nutrients to the baby) so much so that if the mother exercises in the beginning of pregnancy and then suddenly stops, there is potential for a larger than average baby with higher fat percentage because the placenta has adapted to the stimulus of a reduction in uterine blood flow.

(Image: Exercising Through Your Pregnancy, Clapp). 

Nauseous? For some, nausea can be debilitating. But for those whose nausea is less severe, while you may not feel motivated to get outside and move, I found that my nausea all but disappeared once I was outside and raising my heart rate. I’ve heard that anecdote among many other pregnant athletes and it has led me to wonder if exercise may be a prescription to temper first trimester sickness. It’s counter intuitive to feel tired and nauseous and motivate for a workout, but getting out immediately in the morning was the key to having the most energy and beginning my day with an opportunity to feel better and more refreshed than when I woke up. I realize there are varying degrees of sickness and that some border the line of debilitating; if this is the case, getting through the work day and accomplishing daily responsibilities is likely considered a win. 

During my first maternity appointment my doctor proceeded to tell me all the things I shouldn’t eat or do—unpasteurized soft cheeses, raw seafood, ski, mountain bike— she then qualified her advice by telling me of her very adept friend who skied her entire pregnancy because skiing was like walking for her and admitted, “we don’t really have substantial research for our recommendations because no one is willing to run studies on pregnant women”. She also recommended the book, Expecting Better, by Economist Emily Oster—its premise is “why the conventional pregnancy wisdom is wrong and what you really need to know”. Reading between the lines, my interpretation of her comments were that though she feels a responsibility to recommend the most conservative approach, it’s important to know the data behind the risks and come to a solid reasoned decision on your own. 

140 miles with Kristin at SBTGRVL–10 weeks

If you’re curious about the actual statistics behind the rules you’ve heard laid out for pregnancy, I’d highly recommend this read. For example, after looking at the data, the author found that avoiding ham sandwiches (deli meats are said to be off limits), she would have lowered her risk of listeria infection from 1 in 8,333 to 1 in 8,255. Sure there is risk, but seeing the actual data demonstrates the risk is VERY marginally increased. I much appreciated and relate to Oster’s approach in wanting to know the actual risk so that she could make her own data driven decision rather than just being told “it’s best to avoid x”. Turns out, the author reaches conclusions that sushi risks are extremely minimal (raw shellfish is what is to really be avoided) and coffee consumption is considered safe at 200mg a day, potentially 3-4 cups a day, even. 

But what if you fall? As the pregnancy progresses, there is a chance that balance can be compromised. This varies individually, but it also is important to assess one’s natural skill level in an activity to assess risk. A highly proficient road cyclist or mountain biker may have a much lower risk of falling as compared to someone who is only intermediate in skill. There is also terrain to consider, as one can reduce risks by riding on lower trafficked roads or less technical terrain to minimize fall risk. Research has revealed that there is not an increased rate of falls in regularly exercising versus non-exercising women (Clapp, 2013). While blanket recommendations are advised and many sports are considered off limits, there are a multitude of factors to consider and at the end of the day, the risk is weighed and the individual should do a “gut check” to make the decision that feels best for them. You could cut out every potential dangerous activity and then get in your car tomorrow and be rear ended (the statistics are one in 50 that you’ll experience a car accident in a year) and we take this calculated risk daily. 

VT Overland, 11 weeks
VT Overland Podium, 11 weeks
Congrats to Regina Legge and Lyne Bessette on 1st and 2nd place

Another layer to the risk equation is the consideration of the level of joy and reward that the activity brings to the individual. I think it’s important to be honest with oneself about the risks, take steps to mitigate the risk but not discount the satisfaction that is also reaped from the activity. There’s something to be said about being able to feel levels of “normal” when much is changing with your body and out of your control and participate in the community of sport (for me this is in the form of riding with others). Cycling is highly therapeutic in its own right and as many women are susceptible to symptoms of depression during pregnancy and after birth, it’s worth considering how your activity boosts your overall well being and mood.

In addition to some incredible efficiencies, there are also decreased risks should one keep up an exercise program during pregnancy:

  • Less low back, leg or pelvic pain than controls (less than 10% vs greater than 40%)
  • Decreased risk of cesarian section (9% vs 29%)
  • Decreased pregnancy weight gain (which would later be correlated with decreased gestational diabetes, pre-eclampsia, and cerebral palsy)
  • Decreased postpartum weight retention (1/3 of the weight retention at one year compared with controls)
  • Decreased risk of acute low back injury (which resulted in an extended period of pain in physical limitation in a number of the non exercising controls)
  • 50% decreased risk of induction of labor
  • Decreased risk of gestational diabetes
  • Larger placenta with improved oxygen delivering capabilities
  • Lower fetal heart rate and increased heart rate variability (signs of good cardiovascular health)
  • Babies with significantly increased ability to calm themselves as soon as five days after birth 
  • Offspring have significantly higher scores on intelligence testing
  • Offspring have significantly better oral language skills 
  • *via Exercising Through Your Pregnancy, Clapp.

Learning from other Female Athletes

For years I’ve followed pregnant elite athletes with an intense curiosity to understand what pregnancy had changed or not changed for them. 

 I’ve been inspired by stories from athletes like Erin Drasler (also an ER physician), who completed the entire Leadwoman competition while between 9-18 weeks pregnant—that’s the Leadville Trail Marathon, Silver Rush 50 MTB or Run, Leadville Trail 100 MTB, Leadville 10K Run and Leadville Trail 100 Run all above 10k feet of altitude.

Michelle Vesterby, pro triathlete, competed in the Hawaii Ironman at 11 weeks pregnant and vied for the podium at Ironman Cozumel at 15 weeks pregnant.  She maintained around 25-30 hours of training throughout her entire pregnancy (albeit at a lower intensity) and was able to compete in an Ironman a mere 3 months after giving birth. 

Michele Yates—a pro ultra runner, managed to maintain running around 80 miles a week throughout her pregnancy. Pregnancy did not thwart her performances and podiums— at 9.5 weeks pregnant, she ran the 2014 Cimarron 50k at an average altitude of 8,400 feet in 4:41:55 and won. Then she finished second female in 12:01:50 at the 2014 Gunnison 100k at four months pregnant. Finally, she took second female at the 2014 Waugoshance Trail Marathon in a time of 3:46 at five months pregnant.

Entrepreneur and Pro Triathlete Beth McKenzie was also a huge inspiration as I closely followed her comeback to sport following the birth of both her daughters. She competed in Ironman Malaysia four months postpartum and finished in an impressive fifth place, among many other impressive feats. But where I’ve really taken inspiration from her story is the pace of life, international travel and competition that she and her pro triathlete husband Luke McKenzie were able to maintain. Their first daughter had traveled to 5 continents and 11 countries by ten months old. Many have asked me, “how will you maintain your pace of life and travel” and while time will tell, I have strong ambitions to continue the same kind of lifestyle that we currently enjoy, meaning fast paced with some work, travel and adventure sprinkled in.

While I realize that pregnancy and parenthood is a practice in letting go of control and that health issues or unforeseen challenges may present themselves that are unexpected, there is power in observing what is possible provided a pregnancy is uncomplicated and an athlete begins pregnancy with a solid base of endurance fitness; if this is the case, restrictions in athletic endeavors are likely at a minimum.  It’s important to be informed, especially as pregnancy can be a time of many anxieties and worries–and to know that so long as you’re listening to your body and its signals, the benefits point to outweighing any risks. 

Peacham Fall Fondo ROAM Ride, 15 weeks

Next up:

  • Grinduro
  • UnPaved Pennsylvania 
  • King Challenge
  • Forest Fondo
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Laura King

Californian becoming a Vermonter. Usually found going full 💨 with a full ❤️ all over 🌏 on 🚲 with @iamtedking and baby Hazel King. Prefer the dirt.
Cycling, Trail Running, Swimming, Mountain Biking, Gravel Biking
Richmond, VT

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