There were many people engaged in Buddhist rituals at the Boudhanath Stupa. Some were reciting mantras, some walking around the massive stupa praying, others sat silently in meditation. The most interesting to me were the people that repeatedly stood up with hands clasped in prayer then, in a smooth transition, put themselves prostrate on these boards with arms extended then moving in reverse to stand up with hands clasped in prayer. This was repeated many times. I suspect each person did this 108 times, a sacred number in Buddhism. I imagine they were in pretty good shape with all the exercise.