Regularly doing knee strengthening exercises can decrease everyday knee pain and slow down the progression of knee arthritis. How?

See What Is Knee Osteoarthritis?

When the muscles around the knee get stronger, they are better able to stabilize the joint and absorb shock during weight-bearing activities, such as standing and walking. A stable, supported joint will undergo less friction and wear-and-tear.

See Knee Anatomy

Below are suggested knee strengthening exercises. If these exercises are too challenging, modifications may be used; as muscles get stronger the modifications may be eliminated.

See Exercising with Arthritis

Squats for Knee Strengthening

The squat is a multi-purpose knee strengthening exercise that targets the quadriceps, hamstrings, and buttocks.

  1. Stand with feet shoulder-width apart, firmly planted on the ground.
  2. Slowly bend the knees as if sitting back into a chair, keeping the back straight and the abdominals engaged. The knees should not go forward beyond the toes.
  3. Arms may be raised forward to help with balance.

A reasonable goal is 4 sets of 12. To add difficulty, small free weights may be held in each hand.

Squat Modification 1: A person who is unable to keep his or her back straight may try squatting against the wall.

  1. Position the body in a full squatting position with the back flat against the wall.
  2. Raise the body by straightening the legs and sliding the back up against the wall.
  3. Lower the body using the same method.

Squat Modification 2: This version uses a chair.

  1. Stand with feet shoulder-width apart in front of the chair.
  2. Cross arms across the chest, grabbing opposite shoulders with opposite hands.
  3. Exhale and sit back, moving toward the chair until the thighs are parallel to the ground.
  4. Pause for a moment, and then rise slowly while keeping the core body engaged and back straight.

If the chair feels too far down, place pillows on the seat until it is a comfortable height.

Thigh and Hip Strengthening Seated Leg Raises


This exercise strengthens the muscles in the front of the thigh, the quadriceps.

  1. Sit in a chair with the knees bent, feet dangling above the ground. Add pillows to the seat of the chair if necessary.
  2. Holding onto the sides of the chair for stability, slowly extend left leg until it is nearly parallel to the floor. Try to keep the leg as straight as possible without locking the knee.
  3. Pause briefly holding the leg straight, and then return back to the starting position.

Repeat with the right leg. Perform 3 sets of 12 repetitions on each side.


Side-lying Leg Raise

This strengthening exercise mainly targets the muscles on the outside of the hip.

  1. Lie on the left side of the body and bend the left knee so that the left foot is behind the body.
  2. Slowly raise the right leg until it makes a 45-degree angle with the rest of the body, keeping it as straight as possible.
  3. Pause with leg raised 45 degrees, and then start a controlled lowering to the starting position.
  4. At its lowest position, the right leg should be parallel to the floor—not resting on the floor—if possible.

Repeat the leg raise 8 to 12 times on each side, performing 3 sets. If this exercise seems too easy, add light ankle weights.

Ron Miller is a licensed physical therapist with more than 20 years of experience specializing in spine care. He helped develop the physical therapy department at the NeuroSpine Center of Wisconsin, where he focuses on manual therapy, spinal stabilization, and therapeutic exercises.