During lunges, keeping your knee over your ankle is essential.
Lunges are often referred to as one of the best functional lower-body exercises you can do, but when done with incorrect form, the repetitive motion and the excessive load can wreak havoc on your knees. To prevent this, learn proper exercise form by starting with basic forward lunges using just your body weight. Once you master these, move on to more challenging lunge varieties.
Muscles and Joints
Lunges mainly work your quadriceps at the front of your thighs, especially when you take small steps forward during the exercise. When you take large steps forward, you put more emphasis on your hamstrings at the back of your upper legs. Your glutes, or buttocks, also engage during lunges. The joints involved in this compound exercise are your hips and knees. The latter is made of four bones and uses the surrounding muscles and ligaments to provide motion and stability.
The Lunge Exercise
Lunges look deceptively easy, but there's more to them than meets the eye. This is why it's best to perform the exercise in front of a mirror so you can monitor your form. Start in an upright stance with your feet shoulder-width apart, your back straight and your abs contracted. Breathe in and then step forward with one leg. Bend both your knees and lower your hips to the floor. When your knees are bent 90 degrees and your back knee is close to the ground, push off through your front heel and exhale as you return to the starting point. Then repeat the motion with your other leg.
Correct Lunge Form
During lunges, it's essential that your front knee remains above your ankle and points in the same direction as your foot. If your knee passes beyond your toes or points in a different direction, it can make you lose your balance or trigger joint damage. Draw your belly button to your spine to engage your abs and to help stabilize your body. Also, be sure to face forward and push your chest out slightly to help keep your back straight. At the lowest point of your lunge, your knees should be bent 90 degrees. Avoid going deeper or not deep enough, as this can injure your knee joint. It also keeps you from working your muscles in the most efficient way.
Increasing the Challenge
Once you master basic front lunges, progress to walking lunges, reverse lunges, side lunges and lunges with one foot on a platform in front or behind you. For a greater challenge during any of these lunge variations, hold dumbbells in your hands. Combination exercises can also make for a greater challenge. For instance, combine dumbbell lunges with lateral or front raises, shoulder presses or biceps curls. Regardless of which lunges you do, always make sure the knee of your working leg is above your ankle, not your toes.