There are almost 50 million people in the US that have problems with knees. Proper diet and healthy weight can be a solution to knee-related problems, but if you really want to keep them away from trouble, try these few workouts.
Bent-Knees Chair Raises
Sit on a chair and straighten your legs in front of you. Slowly bend your leg until your foot is on the one-inch distance of the floor. Try staying in that position for a 30 seconds and then return in starting position. Do this exercise four times.
Sliding Down the Wall
Stand straight against the wall and lean back. Slide down the wall until you bend your knees at 30 degrees, then slide up the wall. You can keep hands on the wall to stabilize your body, and do about 10 repetitions of this exercise.
Knee Flexion While Seated on a Chair
Sit on a chair and start this exercise by looping a rope or a long towel under the left foot. Then you need to pull the rope, raising the foot above floor. Hold it for about 12 seconds and then release it. You need to perform it on the right foot as well and do 5 repetitions on both legs.
Knee Extension by Sliding Your Heel
For this exercise you need to lay back on the floor and bend your left knee, while your left foot on the ground. Then, carefully slide the foot, until the leg is straightened. After a second or two, bring back your leg into starting position and repeat on the right leg too. Do 5 repetitions of this exercise.
Chair Raises with Straight Legs
You will need a few chairs for this exercise. Just sit on one chair and put the feet on another. Your legs need to be straight without locking the knee. Slowly lift the leg about an inch or two from the ground and hold it for 5 seconds. Return to the starting position and do 5-10 repetitions for each leg.