The grouping of four muscles on the front of your thigh is called the quadriceps. They are essential in hip and knee movement and in absorbing shock when you walk. You might need to work on tight or weak quad muscles after an injury, surgery or a long period of being sedentary. In addition, if you have knee problems, strengthening your quadriceps can help ease pain in your knee. Before starting stretching or strengthening exercises, get your blood flowing to your muscles by warming up with a quick bit of cardio.
Stand facing the wall, pressing your left hand against it for balance. With your right hand, grab your left foot behind you and pull it up toward your buttocks until you feel the pull. Hold for 10 to 30 seconds, then switch sides.
Lie on your right side with your right leg straight. Reach behind you and grab your left foot with your left hand and pull it toward your buttocks until you feel a pull. Hold for 30 to 45 seconds, then switch sides. Repeat with each leg two to five times. This exercise is similar to Step 1, but you don't have to worry about keeping your balance.
Perform the lying stretch in Step 2, but after pulling the left foot toward the buttocks, push the top of your foot against your hand, as if you were trying to straighten your leg but your hand won't let you. Hold this tension for five to seven seconds, then pull your foot back toward your buttocks. Repeat this back-and-forth three to five times, then switch sides.
Lie on your back with one knee bent. Using slow movements, raise your straight leg to about a foot off the floor, then return it to the floor. Repeat 10 times, then switch legs. Do five sets for each leg.
Stand in front of a step or other low, sturdy platform with your feet about hip-width apart. Place your right foot on the platform, then slowly push off the ground with your left foot so you're standing on the platform with both feet. Replace the left foot back on the floor in starting position, then the right. During the step up and the step down, try to keep your body as upright as possible. Once this exercise becomes easy for you, hold dumbbells in each hand so your quadriceps must lift more weight during the step up.
Stand up straight, then step forward with your right foot 2 to 3 feet. Your front shin should be slightly leaning forward with your thigh parallel to the ground, and your back shin should also be about parallel to the ground. Bend forward slightly but keep your back straight. Return to standing position by pushing off with your front foot. This exercise is more advanced, so attempt it only once you feel you've begun building up strength in your quadriceps.