When I began practicing Ashtanga, some 15 years ago, one mantra that helped me through difficult poses was a classic feminist rallying cry: “Girls can do anything boys can do, only better.” While learning a difficult new pose (like karandavasana) that seemed to require strength I didn’t have, I would repeat this mantra to myself as I tried again and again. And finally, I’d be able to lift myself off the floor as well as the man to my left.

When I practiced in India for the first time, my guru, Shri K. Pattabhi Jois, didn’t seem to endorse my mantra a hundred percent. I was stunned, for instance, when he told me not to practice on “ladies’ holiday.” What was “ladies’ holiday”? A day devoted to shopping or relaxing at the spa? When I discovered that it referred to days of menstruation I was confused, and decided this must stem from traditional Brahmin attitudes toward women and menstruation. And yet in most things, Jois was quite modern. He had, for example, abandoned the tradition of teaching men only quite early on. What’s more, apana vayu, his term for menstruation, was far from archaic; it meant “downward-moving energy and elimination.” Still, I decided to disregard what I saw as discriminatory advice, and continued to power through the practice during “ladies’ holiday.”

But after the first month in India passed, I missed my period. This was very convenient in some ways, albeit troubling in others. After returning to New York and missing three more cycles, I finally decided Jois might know best and began to adhere to his dictum. Within a few months, my period returned, and brought my depleted energy back with it. I did some research and found that many yoga teachers and doctors agreed with Jois, saying that yoga, or at least some inverted poses like the shoulder stand or headstand, should not be practiced while menstruating heavily. Some doctors even believed it might cause endometriosis andvascular congestion in the uterus. One thing my own experimentation showed beyond a doubt is that if I practiced yoga while menstruating, it zapped my energy, increased my flow, and made my period last longer than normal.

Now I feel privileged to have a monthly three-day break from my practice. And besides, just because women can do anything men can do, only better, that doesn’t mean we have to. Does it?