When it comes to arm muscles, the biceps at the front usually get all the attention. Biceps are the glamorous muscles displayed in the classic "show me your muscles" pose, but your triceps make up the bulk of your upper arm size. The triceps are located at the back of your arms and are the secondary muscles involved in pushups, bench presses and other pressing movements. You can isolate your triceps with free weights, or by using different machines at the gym.
The push-down station is a staple in most gyms and an effective way to work your triceps. It is basically a cable attached to a weight stack, with a short, straight handle or rope attached to the cable at the top. Grab the handle or rope with an overhand grip and pull it down to about your chest level. Keep your elbows bent and tight to your body. Slowly straighten your arms, moving the handle down to your upper thigh area while flexing your triceps. Bend your arms to the start position and repeat.
Cable Rope Extensions
Cable rope extensions can be performed on the same machine as the triceps push-down. Use the rope attachment on the lower cable of the machine. Turn and face away from the machine and have a training partner hand you the rope attachment. Reach back and hold the ends of the rope behind your head with your palms facing each other. Start with your elbows bent and hold them close to your head, pointing toward the ceiling. While keeping your upper arms still, extend your elbows and pull the rope handles toward the ceiling. Pause for a count of two at the top of the pull, slowly return your hands to the starting position and repeat.
The dip machine is basically the same as doing a regular dip, only the handles of the machine move instead of your body. Sit in the seat facing out and place your feet flat on the floor. Check to see that the handles are just below your arm pits and if they are not, adjust the height of the seat. Grasp the handles and start with your arms bent 90 degrees. Press the handles down, flexing your triceps at the bottom, and then allow the handles to rise back up again.
Hammer Extension Machine
The hammer extension machine resembles a preacher curl machine, but the movement is reversed so you are pushing away instead of pulling in. Adjust the height of the seat so the edge of the padded arm rest is just below your arm pit. Sit on the seat and place the back of your arms over the pad. Grab onto the handles and straighten your arms down, flexing your triceps.