Triceps exercises engage all three heads of your triceps.
Your triceps make up approximately two-thirds of your arms, and any comprehensive arm workout should include significant effort and attention to your triceps. Your triceps, anatomically known as the triceps brachii, consists of the long head, medial head and lateral head. Writing for "Ironman" magazine online, personal trainer Ingrid Barclay says that all three heads of the triceps work together, but you should do different exercises and vary your arm position to emphasize different parts of your triceps.
Know Your Triceps
The primary role of your triceps is extending or straightening your elbow. The long head, also known as the inner head, runs along the inside of your upper arm and is the largest of the three heads. The lateral head, known as the outer head, is the most prominent, and runs down the outside of your arm. The smaller medial head lies between, and is largely covered by the long and lateral heads.
Do Dips for Strong Triceps
Dips are a multi-joint body weight exercise that simultaneously work your chest, anterior deltoids and triceps. Dips equally work the long head and lateral head of your triceps with the medial head kicking in at the top of the movement. Ensure you emphasize your triceps by keeping your body upright as you perform the exercise. Leaning forward emphasizes your chest and shoulders. Do two or three sets of 10 to 15 reps. Once you can do 15 reps, add resistance by attaching a weight to a dipping belt.
Work with Skull Crushers
Triceps exercises with your arms placed in front of your body or above your head emphasize the long head of your triceps, according to exercise physiologist Jim Stoppani Ph.D., writing for Muscleandfitness.com. Skull crushers on a flat bench with your arms at right angles to your body place equal focus on the long and lateral heads. But skull crushers on an inclined bench move your arms more above your head, and shift the focus onto the long head of your triceps. The medial head kicks in on each exercise as you lock your elbows out. Do three sets of either exercise with a weight that allows you to do 10 to 12 reps. The last two reps should require some effort and leave your triceps burning.
Get Down with Pushdowns
Triceps pushdowns emphasize the lateral head of your triceps, according to Barclay. To effectively target your triceps, use a thumbs over grip and push down with the heels of your palm, not your fingers. Lock your elbows out at the bottom of the movement to engage your medial triceps. Keep your elbows tight to your side and move only your forearms. Do three sets of 10 to 12 reps.