Nairobi, Jan. 4 -- Samuel Muthama does yoga every day.

"My routine includes a morning and evening session, each lasting about 10 to 15 minutes. In the morning session, I do movements that awaken my body and allow blood flow, then in the evening I do more of the breathing practices, which allow me to calm down, let go of the day, and get into rest mode," he says.

He adds: "And then for three days in between the week, I do complete one-hour sessions as part of my fitness regimen, which also involves gym workouts and things like walking."

When he started, his friends had opinions.

"Those things are for women," some said. "It's a cult," others declared. But Samuel was not moved. Having tested and tried yoga, he didn't argue. Instead, he i...