I have been training for about 14 months at a local gym. I havent been in a fight yet, but have sparred many, many times with other boxers from my gym and other local gyms. I am 5'9", 158 lbs, (very lean, 11.9% body fat) I have never in my life been heavy, never been in any kind of accident or serious injury at all.

About a month ago, i noticed that my knees were starting to hurt after workouts. Its not a cracking or popping, its just a pain that feels like its coming from the center of my knees. I train 3-4 days a week usually, so i took a week off from the gym and the pain goes away by the end of the rest week. I have a doctors appointment for an Xray and possible MRI next week. Im hoping that I dont have any serious problem like weak cartilage that will make me stop training.

Does anyone have any idea's what could be wrong with my knees?