I got a sore butt muscle, left glute or piriformis, pain so deep it's in the "capsule" of the hip bone socket. With sprinting, you tend to really jack muscles you don't normally use. Problem I have is I can't stretch it loose and no way does icing it go that deep through all the fat and muscle. It's not so bad that I can't sprint or workout. Just kind of a dull reminder that I'm 52.
When I can't sprint, I do kettlebells to burn the fat.