Degrees are used to measure the range of motion in your knees certain activities require. You need 65° range of motion to walk, 70° to pick up something from the floor, 85° to climb stairs, and 95° to sit and stand comfortably. [1] X Research source

The iliotibial band, or IT band, is the area of thicker tissue that runs from the outside of the pelvis to the outside of the knee. The IT band helps to stabilize the knee during physical activity. It can become inflamed and painful when it is overused, leading to iliotibial band syndrome (ITBS). Runners, hikers, and other active people often experience this injury. The anterior cruciate ligament (ACL) is commonly torn during activities like running, jumping, and landing from a jump. Other ligaments may be torn as well. The meniscus, which acts as a shock absorber to protect the knee joint from impact, can be easily torn during activities like twisting, pivoting, or decelerating.

Muscles like the quadriceps, hamstrings, hips, and glutes act as stabilizers for your knee. To help improve your stability, you should exercise and stretch these muscles. [3] X Research source

Stand with your left foot crossed over your right and stretch your arms above your head. Lean your upper body as far as you can to the left without bending your knees. Repeat with your right foot crossed over your left, leaning your upper body to the right. Sit on the floor with your legs stretched in front of you. Cross one over the other and pull your knee as close as you can toward your chest, holding it in place for a few seconds. Repeat with your other leg. Take a brisk walk before launching into a more complicated exercise to give your IT band a chance to loosen up.

Seated knee flexion: Sit on a firm chair, and slide one foot back under the chair as far as you can. Your thighs should remain firm on the chair. Hold for five seconds before sliding back forward. Repeat with the other leg. Seated knee kick: sit on a firm chair with your legs bent. Raise one leg slowly until it is completely straight. Hold for five seconds before lowering the leg. Repeat on the other side. Straight leg raise: Lie down with one leg bent and the other straight against the ground. Raise the straight leg up slowly before lowering it back down. Repeat on each side ten times. [5] X Research source

Thigh squeezes may help those who have had long-term knee problems or knee surgery. Lie down with your legs straight. Squeeze the muscles at the front of your thigh, and hold it for five seconds before releasing. Make sure to do this with both legs. [6] X Research source Do lunges to work on your quadriceps. Stand upright with your hands on your hips. Take a big step forward with your left foot, and lower your body toward the floor until your left leg is bent at a right angle. Your back knee will lower until it is nearly touching the floor. Repeat this exercise several times, then switch to the other side. Low-impact exercise machines such as a stationary bike or elliptical machine can help you work out your quads with minimal or no impact. These are safer activities for someone who has arthritis or a previous knee surgery than running is. [7] X Research source

Touch your toes. Stand straight, and bend forward while keeping your spine straight and your abs contracted. Straighten back up. If you are having trouble reaching your toes or ankles, place a chair in front of you. Bend forward to try to touch the seat of the chair. [8] X Research source Heel lifts might also help. Start by either standing feet parallel and facing forward. Lift your heel back to try to touch your buttocks. Try donkey kicks. Stand behind a chair, and place your hands on the chair back. Raise one foot behind you, with the knee bent. Lower the foot back down to the ground. Repeat with both legs. To do a bridge, lie down with your knees bent. Squeeze your glutes as you slowly lift your hips a few inches off of the ground. Hold for a second before slowly lowering yourself back down. This exercise will not only work your hamstrings but also your hips and glutes. [9] X Research source

Try a clamshell. Lie on your side with your knees bent. Lift the knee of your top leg, but keep your feet touching. Hold for a second before lowering. Repeat ten or twelve times before switching to the other leg. [10] X Research source Squats with a short range of motion are good even for people with knee problems. Stand upright and simply squat to the ground, bending your knees and keeping your back upright. For a less strenuous version of this exercise, practice standing in front of a chair, sitting, and standing again.

Yoga is a low-impact activity that tones your leg muscles. Swimming is another great way to build leg and knee strength and flexibility because it is a no-impact activity. Walking and biking keep your legs and knees in shape for more strenuous activities.

Fish, flax seeds, olive oil, avocados, and whole fruits and vegetables are said to have anti-inflammatory properties.