Patellofemoral pain and chondromalacia patella (CMP) can restrict a client’s ability to perform traditional strength training exercises. Pain with loading and movement can also inhibit quadriceps activation. This exercise can be safely implemented to help facilitate quad strength for those limited by anterior knee pain.
Execution:
Set up the knee extension machine so that the axis of rotation is in line with the knee joint and the start angle is approximately 90 degrees of knee flexion. Ensure that there is sufficient weight on the stack in order to prevent any movement with exertion during the exercise.
Next, adjust the pad so that iit s above the ankle and against the lower part of the shin, Lift up and press the shin against the pad with maximum effort for 5 seconds, relax and rest for 5 seconds. Repeat 10 times. Switch legs if needed and perform 1-2 sets. Change the angle if multiple angles are desired or needed based on client feedback. Typically, I suggest angles between 90 and 45 degrees as there is limited shear force and stress on the patellofemoral joint.
Regression:
If there is discomfort with the single leg version, attempt the same exercise using both legs at the same time. However, put the maximum amount of weight on the stack to ensure the shin pad will not move.
Progression:
Once the isometrics become easy or the client wants a bigger challenge, advance to a limited range single leg isotonic knee extension in a pain free range of motion while avoiding the last 40-45 degrees of extension to minimize shear force on the patellofemoral joint.
Application:
This exercise is very effective for clients who are limited in their ability to do more traditional exercises such as squats, lunges, step-ups, etc. due to anterior knee pain. This exercise allows for isolated quadriceps activation and strengthening using time under tension in a pain free manner. With clients affected by anterior knee pain or abnormal patellar tracking, this isometric approach can offload the joint and allow for pain free strengthening until the client is able to transition back to more traditional exercise.
