question: Hi, I was wondering what might be happening to my knees while I m jumping. Below my kneecaps and at the top of bone below that there is a sharp pain and it feels like my legs could pop right out. My parents think that this is a result of not stretching before going jumping but I do not know why it would make my leg feel like it could burst out right below the knee cap. It would be great to know if this can be prevented or cured from the pain. Thanks.