You use the gastrocnemius muscle, found in your calf, frequently when you step forward, run, step up and any time you lift onto the balls of your feet. This muscle is responsible for plantar flexion of the ankle and also assists with bending the knee. Although variations in equipment exist, most gastrocnemius strengthening exercises are basically one of four kinds.
The calf raise is arguably the most well-known gastrocnemius exercise. Standing calf raises specifically target the gastrocnemius, and seated calf raises emphasize the soleus, which is a smaller muscle of the calf. You can choose between calf raises with only your bodyweight, holding a barbell or dumbbells, or using a weight machine. All calf raises involve standing up and lifting onto the balls of your feet, but a unique calf exercise is the donkey calf raise. You use a donkey calf raise machine to perform this exercise. Stand on the foot rests and bend over, placing your lower back against the pad and your forearms on the arm pad. Then, raise onto your toes, which causes the back pad and the weight to lift.
The calf press is a different type of calf exercise. Calf presses still utilize plantar flexion of the ankle, but instead of standing up straight and lifting onto your toes, you press your foot forward into flexion against weight. An example is the sled vertical calf press using a machine named for the exercise. To use the machine, lie with your back on the pad and extend your legs straight and perpendicular to the floor to touch the balls of your feet to the platform. Then, press forward with your toes to raise the platform.
The calf extension is a gastrocnemius exercise using a calf extension machine. The calf extension machine has two separate foot pedals so that you can either use the machine with both feet together, or by alternating, to isolate each calf individually. To perform the alternating seated calf extension, sit on the seat with your back against the pad and place the balls of your feet on the pedals with your legs straight. Keeping your legs straight, extend the toes of one foot forward. Alternate feet.
Plyometric exercises are jumping exercises. Jumping strengthens the gastrocnemius because the calf muscle activates when you rise onto the balls of your feet and push into the air. Jumping forward or sideways works the gastrocnemius. Examples of plyometric exercises include forward linear jumps, lateral hurdle run, cycled split-squat jump, alternate leg push-offs and box jumps. All of these exercises have jumping in common. A basic jumping exercise that works the calves is the jump and reach. To perform this exercise, bend your knees into a deep squat until your heels almost lift off the floor as you extend your arms behind you. Then, jump straight up and swing your arms forward to propel you into the air as you reach overhead.
Even if you're keen on strengthening your gastrocnemius muscles quickly, you must always give your muscles time to adequately recover between workouts. The U.S. Department of Health and Human Services advises performing strength-training exercises twice a week -- ideally, leave a day or two of rest between workouts, and don't just target your calves. You must always exercise all your major muscles. Your familiarity with strength training dictates the intensity of your calf exercises; start with body-weight resistance for exercises such as calf raises and add resistance in the form of free weights as you gain strength.