A strict teacher, B.K.S. Iyengar sometimes hit his adult students. Once, when a couple brought a dazed boy to him, and the boy said that he was dazed because he had achieved spiritual enlightenment, Mr. Iyengar gave him a tight slap and cured him. When foreign female disciples expressed an interest in him, he wrote in his book “Light on Life,” “My flashing eyebrows and fierce glare came to my rescue.” And, when the Vatican approached him to teach yoga to the pope in secrecy he agreed, but on the condition that if someone asked him whether the news were true, he would not lie. The Vatican withdrew the request.

Mr. Iyengar — who died last year at the age of 95, surprising many with his mortality — was largely responsible for liberating yoga from men like himself and creating the circumstances for it to infect the world and in the process win the adoration of Indians.

When he was learning yoga in the India of the time, he wrote, “I can assure you that spiritual democracy did not exist.” The great gurus were secretive and parsimonious with what they let out. Things got worse for him when he began to teach. In 1954, after returning from his first teaching trip outside India, he stopped by the house of a maternal uncle in Bangalore, but he was not allowed in. A Hindu was forbidden to cross the sea, so he had become impure. And, since he was teaching women, “It was generally assumed I was guilty of immorality.” So he got married.

Yoga is today the preserve of women, and there is an ever-failing campaign to lure men to the exercise. In January, in Goa, I went to meet Patrick Broome, the yoga coach of the German soccer team that won the 2014 World Cup. He told me that many players on the squad were embarrassed to be seen doing yoga, because they thought it was feminine.

“Some liked it, some didn’t care,” he said. “Some needed an excuse to come to the yoga studio. So they made it look like an accident that they had landed in the yoga class, as though they were searching for the gym and had got lost.”