The hamstrings and quadriceps muscle groups each contain tendons that cross the knee joint. You may develop tendinitis, or inflammation, in the knee if these tendons are stressed repetitively, such as during sports involving jumping or running, over a period of time. Perform physical therapy exercises to strengthen and stretch the affected musculotendinous units if you suffer from tendinitis. Start with very light resistance and progressively increase the resistance over time.
Lunges
Lunges target the quadriceps muscles -- the rectus femoris, vastus intermedius, vastus lateralis and vastus medialis -- on the front of the thighs through knee extension and flexion ranges of motion. These muscles share the quadriceps tendon, which attaches these muscles to the patella, or knee cap. You may develop quadriceps tendinitis if you participate in jumping, kicking and/or running activities, such as basketball, soccer and volleyball. To perform lunges, stand upright with your feet about hip-width apart. Hold your arms at your sides. Step forward with your left foot 2 to 3 feet and then flex your left knee to lower your hips. Allow your right heel to come off the floor. Stop when your thigh is approximately 45 degrees to the floor, then extend your knee, step back to the starting position and repeat with your right leg. Progressively deepen the squat phase of the exercise over time.
Hamstring Curls
The hamstring tendons cross the back of the knee joint, adjoining the three hamstring muscles to the bones of the lower leg. Perform hamstring curls through flexion and extension ranges of motion to treat hamstring tendinitis. The exercise is performed on a specialized machine with a bench and a padded foot bar, which is attached to a stack of weights via a pulley system. Lie face down on the bench with your knees over the edge. Place the back of your ankles under the foot bar. Hold the handles under each side of the bench to secure your body. Repeatedly flex your knees, arcing the bar toward your buttocks, and slowly return to the starting position.
Hip Abduction Exercise
The Summit Medical Group recommends the hip abduction exercise as one in a series of exercises to treat tendinitis in the knee. Lie on your side opposite the affected knee with your legs straight and stacked. Rest your head on your arm. Flex your ankles so your toes point in front of your body and lift the affected leg 6 to 12 inches upward, separating your legs. Keep your toes and knee directed forward. Return to the starting position slowly and repeat. Perform the exercise on the opposite side as well to promote muscular balance. Wear ankle weights for added resistance if desired. You can also perform the exercise from a standing position using a resistance band. Attach one end of the band to a sturdy object near the floor and the other to your ankle. Stand with your healthy leg nearest the object and stagger your feet slightly, so the band crosses the top of your healthy foot. Repeatedly lift your leg sideways to stretch the band away from the object and return to the starting position.
References
- "Basic Biomechanics"; Susan J. Hall; 2007
- MayoClinic.com: Tendinitis
- American Council on Exercise: Forward Lunge
- "Essentials of Strength Training and Conditioning"; Thomas R. Baechle and Roger W. Earle; 2000
- Summit Medical Group: Patellar Tendonitis
