How to Improve Leg Strength When Swimming

To improve your swimming speed, you must condition your entire body, including your legs. Leg strength doesn't always translate into increased swimming speed, but conditioning your legs in the proper way can help you swim faster. This includes strengthening the ankles and hip flexors, two areas that are harder to work outside the pool.

An egg-beater kick isn't a style you'd normally use while swimming, but it propels the body and uses the resistance of the water to build your leg strength. Lie on your back in the water with your hands by your sides. Push your body backward through the water by performing half-kicks. Kick one foot out and then the other foot, keeping the knees bent and up. This half-kick works your legs in a different way than standard kicks, engaging the hips by helping control the movement and allowing your ankle to perform much of the propulsion. The deeper the knee bend in this exercise, the more strength you can gain in your legs.

Using a kickboard can help you focus your workouts on your legs. Using proper form is key to strengthening your legs. Hold the kickboard in front of you with your hands to increase your buoyancy, then hold your head down in the water; a snorkel is helpful to keep your head still. Kick near the surface of the water, breaking the surface slightly without intense splashing. Use your entire leg, including your hip flexors, to move your body in the water. Hold your abdominals tight to keep your body straight.

A flutter kick uses small movements for big propulsion. The short, controlled movements can strengthen your hip flexors, legs and ankles. Start by holding on to the side of the pool with your legs stretched out behind you. Alternate kicking your feet underwater, moving them no more than 18 inches. The small movements let you kick faster. Once you've mastered the move, try it with the freestyle stroke across the pool.

Flippers, or fins, have a wider surface area than your feet. They can help you move more efficiently through the water, but the wide surface area requires your legs to work harder to push them up and down. Use a slow, controlled and fluid movement while swimming with fins. The trick to faster kicking is to strengthen the muscles while swimming; leg strength itself doesn't mean the muscles can move together in a way that improves your swimming speed. Fins act almost like weights for your legs, allowing you to move them normally in the water but with increased resistance to strengthen them.