Ask a PT Response: "From what you describe, it definitely sounds like you may have overused it. Your quadricep might not have been ready to handle all the increase activity which you have mentioned. When someone is experiencing what you describe, it is generally wise to cut back on the activities which may have resulted in your current condition. Therefore, it sounds like you are doing the right thing by no longer running and performing less strenuous activities such as biking and walking. Straight leg lifts along with quad sets, short arch quads, partial wall slides, standing terminal knee extensions, partial forward lunges, etc. would be some initial exercises which a PT may prescribe. Progression of quadricep strengthening could then include leg press, squat rack, single leg squats, and other functional based quadricep strengthening exercises. Stretching of the quadricep and hamstring muscles would be most likely prescribed as well. As far as the elliptical goes, therapists' would generally have the patient build up their tolerance level, meaning increasing time or intensity over time in accordance with the patient's tolerance level. Exercise should generally not make a patient's condition worse. Good luck with your condition and should you have any further questions, please don't hesitate to contact us."