At 8 months pregnant, I had chronic acid reflux, vaginal varicose veins, and a growing inability to take a deep breath. Some days, it felt like I was running a marathon. Turns out, I was.
According to a new study out of Duke University, pregnant women who carry a baby to term reach the same peak levels of endurance as Ironman competitors. Researchers looked at participants in the 120-day Race Across the U.S.A., finding that moms-to-be expend the same amount of energy as the high-level athletes competing in the 4,800 km race from California to Washington, D.C.
But where the athletes burned the majority of their calories off the top, eventually levelling off at 2.5 times their resting metabolic rate to preserve energy, an expectant mother maintains an only slightly lower rate of 2.2 times her resting metabolic rate?and sustains it throughout her entire pregnancy. Finally, scientific proof of what mothers have always known: pregnancy is an extreme sport.

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