Triceps Brachii Muscle

Triceps Brachii Muscle

The Triceps Brachii is the big muscle on the back side of your upper arm and has 3 heads. That's where the name "Tri - Ceps" (tri = 3) comes from. Its function is to extend the arm. The biceps flexes the arm. The triceps brachii muscle is often simply called triceps. The word brachii means "arm" and triceps just means muscle with 3 heads. So if you are talking about the triceps, you could also mean another muscle with 3 heads. However, everybody associates "Triceps" with the Arm Triceps (triceps brachii). The triceps makes up about 70 percent of the upper arm size. The rear delts cover the upper part of the triceps. Find exercises and information about other muscles at weight training main.

Description

  • Lateral Head (caput laterale)
    The lateral head of the triceps brachii is the outer muscle that goes from the shoulder towards the elbow and has a half moon shape. When you do triceps extensions and use a bar where you palms face each other, you focus on the lateral head of your triceps brachii.
  • Long Head (caput longum)
    The long head starts at the shoulder blade right under the shoulder joint. Triceps Kickbacks are very good for the long head and the upper part of the lateral head.
  • Medial Head (caput medial)
    The medial head of the triceps brachii starts on the inner back side of the upper arm bone. A few cm before the elbow joint, lateral head and medial head run together to one thick tendon. When you do triceps extensions and use a straight bar where your thumbs point towards each other, you focus on the long head and the medial head.

Advice

  • Stretch your triceps between sets and exercises.
  • If you want big arms, don't only focus on your biceps training. The triceps makes up almost 70 percent of the upper arms volume. The biceps only 30.