It's like they are growing pains, but I have been done growing for quite some time now. It's not like my muscles, tendons, etc. are inflexible, it feels like there is something wrong in the joint. Like a bone pain. I fractured my growth plate when I was 16 in my hip (I am now 18), and it feels like the same pain, only to a lesser degree. All the kinds of stretching aren't getting anywhere. I am flexible in my legs, back, etc... but for some reason my hip joints feel hurt so much when I do high kicks. It's been this way since I started kickboxing. Anybody experience this or offer some advice?