When used correctly, ankle weights can increase muscle mass and alter the intensity of your workouts. Ankle weights usually are small weighted belts that wrap around your ankles, held together with Velcro straps. They are widely available at fitness outlets and usually are found in the stable of weights at gyms and fitness centers.

Aerobic Exercise

Ankle weights add resistance to your legs when you're doing aerobic workouts or while running or walking. Ankle weights can raise your heart rate levels by as much as three to five beats a minute and increase oxygen uptake 5 to 10 percent, according to the American Council on Exercise. At the same time, wearing ankle weights while doing aerobic exercise puts you at higher risk of injury. They can alter your techniques and your gait significantly and lead to an injury or accident.

Target Muscles

The muscles most likely to benefit from exercises that incorporate ankle weights are the quadriceps, or thigh muscles. Strong, developed thigh muscles are an important part of rehabilitation following a knee or lower leg injury, and they take the pressure off weakened knees for walking and climbing. To build thigh muscle mass, you should strap on the weights to your ankles and sit on a sturdy chair. Slowly lift one leg and hold it straight out for a count of 10 and slowly lower your leg. Repeat 10 times and then repeat on the other leg. You'll feel your quads tighten and grow as you continue.

Variety

Ankle weights can significantly increase the resistance for a number of exercises. In addition to building muscle mass, they can aid those with degenerative joint disease such as osteoarthritis to build sufficient muscle mass to take the pressure off aching joints. Attach ankle weights when you perform standing hip abduction exercises. To build inner thigh and glute muscles, don ankle weights ranging from 1 lb. to 3 lbs., depending on your strength. Stand behind a sturdy chair to hold for support and slowly lift one leg to the side as far as you can. Hold for a couple seconds and return to the original position. Repeat 10 times on each leg. Continue holding the back of the chair while you lift your leg backwards, hold and lower it 10 times on each side.

Intensity

In addition to aiding rehabilitative situations, ankle weights can be an appropriate equipment choice for athletes looking to intensify their workouts, according to the American College of Sports Medicine. Exercises should be performed two or three times per week in three sets of 10 to 20 repetitions for maximum benefits. Ankle weights can build additional muscle mass and strengthen your back through exercises such as side planks, front planks and the bird dog. Add intensity and build additional muscles doing leg lifts with ankle weights by sitting on a stability ball during the routine. The core engagement required to maintain your balance on the ball increases the overall fitness benefits and increases the amount of mass you can develop in your quads.