woman doing lunge

Your quadriceps (thigh muscles) are powerhouse muscles. They're the strength behind many of your daily activities, from walking and running to bicycling and swimming. They help improve your performance by flexing your hip and extending your knee--a motion vital to performance in most sports. If you feel your workouts aren't all they could be, give yourself a leg up by strengthening your quadriceps muscles. The following exercises are easy enough to practice at home.

Begin by standing straight with your hands at your sides. Take a large step forward with your left leg. Bend your knees from this straddled position, lowering your right knee as close to the floor as possible and keeping your right knee at a 90-degree angle. Pause briefly and then lift up to the starting position. Switch legs and repeat the exercise to complete one set. Continue alternating legs for 10 to 12 sets.

TIP: To increase intensity, hold a free weight in each hand while performing the exercise (experiment with low weights of two, five, or 10 kilograms, depending on your upper body strength). You can also increase the demand on your quadriceps with a shorter forward step.

Begin by standing straight with your hands at your sides. Imagine you're about to sit back in a chair: focus most of your body weight on your heels and inhale as you begin the motion of sitting down, keeping your back as straight as you can. See how low you can hold the position comfortably, but don't allow your knees to extend past your toes or bend further than a 90-degree angle.While keeping the correct form, pause for a few seconds once you reach your limit.Then exhale and return to the starting position.

TIP: To intensify this exercise, add free weights as described in the lunges exercise. Try pausing longer at the bottom of your squat--see if you can increase your hold to between 10 and 30 seconds, remembering to breathe deeply.Advanced athletes can try a one-legged squat by placing their left foot on their right knee and following the instructions above for a very challenging pose.

This is a great quadriceps workout that you can do on any staircase, indoors or outside. You can also use an exercise step at home or in the gym. Begin by facing the steps at the bottom of the flight of stairs or in front of your exercise step. Put your left foot on the step in front of you and push your body upward onto the step by fully extending your left leg. Then place your right foot on the step so that you are now standing with both feet on the step. Step down with your right foot first, then your left, returning to the starting position. Alternate leading legs, until you've completed 10 to 20 step-ups.

TIP: Make the challenge harder by choosing a higher step.

Lying Leg Raises
Begin by lying on your right side on the floor (or on a carpet or rubber mat for greater comfort). Keep your body as straight as you can while extending your right arm above your head to the floor. Rest your head on your right arm. Your left arm can lie comfortably across your body. Then,inhale as you lift your left leg into the air. Pause briefly then lower it down to the starting position before switching legs.

TIP: Try to complete 15 to 20 lifts with each leg.

Jump Squats
This is a challenging exercise for a more serious quadriceps workout. Stand with your feet shoulder-width apart and your hands by your sides. Keeping most of your weight on your heels, begin to sit down as though lowering yourself into a chair. Once you've gone as low as you can go comfortably, pause for a moment and jump into the air.

TIP: Make sure that you've mastered the exercises above before attempting this quadriceps-burner!