A lot of people make the mistake of pulling the leggings up from the waist and then start the activity. This is far from ideal because due to the high-compression nature of spandex, they will immediately ride down if you just pull them up from the waist. You need to make sure the fabric is pulled up by grabbing it in this precise order: calves, inner thighs, and then quads. Basically, the same way women wear pantyhose but of course, that may be a totally foreign concept to you, ha!