Pregnancy Is Literally As Hard As An Endurance Sport

by Teresa B. Duffy
Originally Published: 

I was sitting in pigeon pose, on a physical therapist’s table, when this thought floated into my mind: “I’m here once a week. Not because I’m an endurance athlete. Not because I ran 35 miles through mountain trails. I’m in physical therapy for birthing babies. That’s ridiculous!”

I must have said some bit of that thought out loud because my physical therapist said something that rocked my mama mind. “Actually, you did do something like an endurance race. A study was recently published correlating pregnancy to an endurance race.” I nearly jumped off the table and hugged her, but I remained reserved and leaned deeper into pigeon pose.

My immediate desire to hug my physical therapist came from a place of sudden validation. Over the past year and a half, I had experienced days when I felt like I had just run an ultra marathon. At the end of those days, and well into the next day, I bonked. “Bonking” is what my circle of friends calls a physical crash when you’re out training or in a race. It’s when your mind says go, go, go! But your body goes slow, slow, slow. There were days as a mom to a 1-year-old and 3-year-old when I felt physically awful all day long.

My husband was usually my voice of reason—my coach. I’d be sitting on the sofa staring at a Netflix original, while I verbally vomited about my day. He’d ask simple questions like, “Did you eat enough calories yesterday? Did you drink enough water today? You do realize you only slept 4 hours last night and maybe 3 hours the night before?”

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My response was always the same. You’re right, I didn’t eat enough. I didn’t drink enough, and I am totally sleep deprived. However, I kept going. Small children depended on me.

As it turns out, I am closer to an endurance athlete than I ever imagined. That’s not my opinion, that’s what six researchers found in a study published by Duke University that focused on finding a limit to human endurance. Apparently and shockingly, pregnant and lactating women live in the limit zone. What the what?!?

The researchers set out to discover if there are limits to the amount of sustained energy a human can expend. Evidently the human body has a limit, and it’s 2.5 times a person’s basal metabolic rate (BMR). You can’t restore the calories burned past 2.5 times your BMR, you can try but your body just can’t metabolize enough calories to replace what you lost. They discovered our bodies can only replace 2.5 times what we burn and that’s typically expended in endurance events like Tour de France or an Ironman.

The researchers also looked at a woman’s BMR during pregnancy and lactation and found that her expended energy is 2.2 times her BMR. Let’s break that down. A pregnant woman is only three tenths behind the energy output of an endurance athlete who is training or participating in an event like Tour de France. I’ll hold on while you think about that recently discovered information.

Okay, are you back? Let’s keep going…

What the researchers didn’t look at in this study was how a woman’s body morphs and changes during pregnancy and after she has become a mother. They didn’t look at the extreme conditions a woman’s body endures birthing a baby, and then rides with bold grace into life as a new mother. After our “race,” when the baby is snuggled against their mama’s chest, we don’t taper. We run even harder.

We don’t have a crew team alongside us handing out Power Gel or Carbo Pro or protein bars. Could you imagine if there were a sleek BMW crew car alongside a new mama with a mattress on the roof? Inside would be a few reliable people ready to let you sleep at 11am while they hold and rock your newborn.

But nope. That’s not real (unfortunately). Pregnancy and postpartum life are not a race, but we are expending a similar amount of energy.

It turns out that my experience was endurance-like. My body grew and safely birthed an 8lb, 12oz baby and then 30 months later, a 9lb baby, both by C-section. I fed both of my babies with milk from my body for a total of 32 months. Additionally, over the past four years, I had minimal crewing, the trails had huge elevation gains, and they got super technical at points. I remember going hard on sleep deprivation and ended so many days feeling like I bonked from a calorie deficit. But I kept going: fueled by love, and lasagna when it was around.

As I shifted my body out of pigeon pose and sat up on the physical therapy table, I felt stronger in that moment. I felt validated in a strange way, just hearing how mothering babies is filled with tests of endurance, both physically and emotionally. I was taking care of my hips and SI joint because I am an endurance athlete and I just finished up the first part of an incredible journey; nurturing our human race through the first leg of life.

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