Developing bigger muscles from the butt down is a confidence builder for some and necessity for others. Regardless of your motive, machines give you the ability to achieve this goal, provided you know which ones to use. The main muscles you need to zero in on are the glutes, quadriceps, hamstrings and calves. Each one of these muscles has specific movement patterns. Your goal is to use a machine that matches that movement pattern.
The leg press has a padded seat and backrest, and a steel platform that slides up and down. During the leg-press exercise, you perform hip flexion and extension, and knee flexion and extension. Hip flexion takes place when you decrease the angle between your thigh and stomach and hip extension takes place when you move your thigh away from your stomach. Knee flexion occurs when you bend your knee and move your heel closer to your butt. Knee extension occurs when you straighten your leg. All of these motions take place during a leg-press exercise. This exercise works your glutes, quads and hamstrings all at the same time. Because you want bigger legs, you need to use a sizable amount of resistance. This machine offers supports to hold weight plates to increase the resistance.
A sled hack squat resembles the leg press in the fact that it works the glutes, quads and hamstrings. The difference is that this exercise is performed in a standing position. The lower part of the machine has an angled steel platform for your feet, and the top has padded supports that you press your shoulders against. During the exercise, grab a hold of the support handles, bend your knees to lower your body and stand back up. Change the resistance by sliding weight plates onto supports on the sides of the sled.
Invented by Jack LaLanne, and improved upon by succeeding fitness experts, the Smith machine is a vertical, steel apparatus that supports a barbell. Because you can adjust and lock the barbell in place along the vertical steel bars, you don't need to have a spotter. Smith machines are used to perform squats. The only drawback is that poor form and too high a weight can cause lower back pain.
As an isolation machine, the leg extension only works one muscle group. The focus muscle is the quadriceps. This machine has a lower padded lever arm, padded seat and backrest, and handles on the sides. Change the resistance by sliding a pin into a weight stack. To perform the exercise, hook your feet under the support and push it up until your legs are just short of locking out. You have the option of working both legs at the same time or one leg at a time.
The leg-curl machine zeros in on the hamstrings on the back of the thighs. In similar fashion to the leg extension, you can change the resistance by sliding a pin into a weight stack. Perform the leg-curl exercise from a face-down position with your lower legs hooked under a padded lever arm. Simply push against the arm to move your heels close to your butt and slowly lower it back down. For a variation, work one side at a time.
Standing Calf Raise
The standing calf raise machine targets the gastrocnemius, which is right below the knee on the back of the leg. This machine has a platform on which to place the balls of your feet, padded shoulder supports and handles on the sides for your hands. Standing calf raises are performed by raising your heels in the air as high as possible then slowly lowering them back down. Depending on the machine, you can change the resistance by adding weight plates or sliding a pin into a weight stack.
Seated Calf Raise
A seated calf raise targets the soleus, which is the other muscle of the calf. This machine has a lower platform on which to place the balls of your feet and padded thigh support that you press against to raise your heels in the air. Increase resistance by sliding weight plates onto a support.