(Pro tip: Wearing a slight heel helps.)

Of course, squat toilets are not unique to Asia, and neither is the deep-squatting position. But so ubiquitous is the position in Asia and so invisible is it in the West that it’s been dubbed the “Asian squat.” The internet is rife with suggestions that most Americans cannot squat properly, an idea with which I particularly enjoyed taunting my white American boyfriend.

But is this true? Were my taunts fact-based? How much is this nature or nurture? I figured I first had to understand the physiology of the deep squat.

Luckily, at least one other person on the internet is as obsessed with squats as me, and he knows something about physiology. That would be Bryan Ausinheiler, a physical therapist in California who has written a series of blog posts about the deep squat. “The squat is a great model for a multi-segmental movement pattern,” Ausinheiler rattled off at the beginning of our phone call. Uh, what does that mean? “The squat is a triple-flexion movement. You’ve got bending at the hips, knees, and ankle, so you have to fold everything up underneath you.” There’s a lot going on.

But the key factor seems to be ankle flexibility. In the words of our editor Ross Andersen, “squatting makes me feel like I might rupture my Achilles.” A 2009 study in Japan found that men who found it impossible to deep squat had particularly inflexible ankles. This is also in part, Ausinheiler said, why kids have no problem squatting. “I measured my daughter’s ankle flexibility when she was one day old,” Ausinheiler said. “She has 70 degrees of ankle dorsiflexion! Normal in the West is, like, 30.” So humans are born squatters; some of us lose it when we stop trying.

In fact, not everyone who can deep squat is, as Ausinheiler put it, squatting “well,” with feet close together and toes pointed forward. I grew up in the United States with few occasions to squat, and I fall into this category. (A fact I was painfully aware of in China, because I had to place my feet wider than the grooved sides of the squat toilet that kept you from slipping on the wet floor.) The position, while doable, is not particularly comfortable for me either. When an editor dared me to write this entire article while squatting, I quickly realized I’d either end up with an extremely short article or a workplace injury.

Body shape also seems to play a role. Short limbs, big heads, and long torsos make it easier to balance. (Again why toddlers have it so easy.) “I have three brothers, so of course, every year I test all their abilities to deep-squat,” Ausinheiler told me. “What I found is, of the four of us, my squat is the best, I gotta say, but I’m also most conscious of technique. I have another brother who has even shorter legs than me. His squat isn’t quite as good as mine, but it is very easy for him. And then the brother with the longest legs has the worst squat. He kind of has a hard time with it.”