Eccentric Exercises for Patellar Tendinitis

Patellar tendinitis, also called jumper's knee, is a degenerative condition affecting the knee. It starts as inflammation of the patellar tendon and can further result in micro- or full tears of this tendon. It is caused by overuse of the knee's extensor mechanism, common in sports that require jumping and hard landing. A number of eccentric exercises can help in the healing process.

Getting Started

• Eccentric training can develop new collagen in connective tissues such as the patellar tendon. These movements involve lengthening the muscle fibers while the muscle contracts. You should also rehabilitate the tendinitis by using the RICE method (see resources), and if necessary, avoiding the sport or activity that initially caused the condition.

  All of the exercises listed below put force on the injured tendon. If done improperly, they will only further inflame and aggravate your condition. Err on the side of caution when doing them. Stop if anything other than mild discomfort occurs.

  Don't be over-aggressive in using these exercises. Instead, build up to a point where you can use weights comfortably. Increase the weight slowly over time.

Eccentric Squats

• Eccentric squats are the primary exercise recommended for patellar tendinitis. You should initially perform these using both legs on a flat surface.

  Keeping both feet flat on the floor, slowly bend at the knees to squat down as if sitting into a chair behind you. Lower your butt until your thighs are parallel to the floor. This part of the movement should take at least three seconds. Hold this position for 10 seconds. Put more weight on the non-injured leg and then return to a standing position. Repeat for three sets of 10 repetitions. Take a break of one minute between each set.

  As you begin to strengthen and heal the tendon, you can increase the difficulty of this movement. Start by keeping your weight evenly balanced on both feet when returning to a standing position. Then begin to add weight, either using a barbell across the upper back, or by holding dumbbells in each hand. When you do not feel any discomfort, shift your weight primarily onto the injured leg throughout the entirety of the movement.

  To make further progress, perform the squat on a 45-degree slope. Start by using no weight, and putting more pressure on the non-injured leg. Then progress as outlined above. To add weight, wear a backpack with weights inside (instead of using a barbell).

  If you begin to feel greater amounts of pain, return to an earlier stage of rehabilitation and begin again. If you do not feel any lessening of discomfort after three to four months, consult a doctor. Some other condition may be causing your knee pain.

Other Strengthening Exercises

• Full rehabilitation of patellar tendinitis should also include stretching of the quadriceps and hip flexors which then progresses to strengthening exercises of these muscles. Lunges, squats and leg presses will work these muscles.

  Take care to focus on the eccentric (downward) phase of each. If necessary, distribute more of the pressure to your non-injured leg when getting started. Shift to more even distribution over time.

  Eventually, you will want to advance to plyometric exercises. To assess your pain tolerance and degree of healing, start with jump-roping. Then begin working sport-specific plyometrics into your workouts (vertical jumps, bounding, one-legged jumps, etc.).