I'm an older yogi in my 50's but do Power Yoga and Ashtanga. These worked better for me by far than any other short. XL is great for a size 36-38 waist. Used them in Costa Rica last week in heat and humidity and they performed great. They are flexible and not too revealing. In fact, I didn't want to wear anything else and am going to order a few more for the summer here in Florida.