Strengthening your quadriceps and other leg muscles also help strengthen and support the knees. You'll need a towel to perform this exercise. Sit with your legs stretched out. Place a rolled towel below your knee, and periodically contract your quadriceps muscles. Feel them tighten. Hold for about 5 seconds, and repeat the process 10 times.
By supporting the quadriceps muscles to flex the leg, knee contractions strengthen the knee muscles. Lay flat on the ground with your legs extended. Place a rolled towel or a foam roll beneath one knee. Always resting your leg on the rolled towel or foam roll, relax the leg then contract the knee and its surrounding muscles. Hold this position for five seconds. Repeat this exercise ten times then perform the same exercise on the other leg.
Using a chair to support yourself, raise your heels and stand on your toes. Do this 10 consecutive times, and repeat the exercise three times. For a more advanced version of this exercise, stand on the edge of a step, whether on a staircase or the sidewalk, and raise your heels standing on your toes. Also perform this exercise 10 consecutive times, and repeat it three times. This exercise not only works your knees, but it strengthens your calve muscles, which give support to your knees helping prevent future knee injuries.
Swimming or using a stationary bike or elliptical machine provide low-impact exercises that can help you stay fit and strengthen your knees without straining them.
Resistance Band Exercise
Strengthening your thighs is also a great way to give your knees better support, thus strengthening them. Using a short resistance band, tie one end to a sturdy structure, like the leg of a table or work-out machine, at ankle-height. Tie the other end of the resistance band to your ankle closest to the structure. Pull the resistance band to the opposing side of the structure. In other words, if the resistance band is tied to a structure on your right, pull your right ankle towards your left. This exercise should work your inner thigh. Leaving the resistance band as if, turning your body around and pulling the band toward the same side, you should work your outer thigh. Perform this activity 10 consecutive times, and repeat the process three times. Repeat the strengthening exercise on the other leg.
Exercise Ball Squats
Standing, place an exercise ball in between your back and a wall. The exercise ball will provide full support for your back, and support your overall exercise style. Separate your feet about shoulder width. Slowly, squat down as if you were sitting. Make sure your toes are only slightly in front of your knees when you squat, otherwise you can injure your knee muscles. Squat 10 times, and repeat the process three times.