The bicep and the tricep are arguably two of the most popular muscle groups in the entire body. Almost every new lifter gets into the gym with two goals in mind:
Build a big chest and attain impressive arms. But, to train our arms optimally, we need to learn what the bicep and tricep are. More importantly, we need to find out how they differ and what that means for us. Let’s dive in.
The Bicep 101 – A Broad Overview
The bicep is a muscle located on the front side of the upper arm. Its primary functions are elbow flexion and wrist supination.
As its name suggests, the biceps has two heads – a long and a short one. Both of them originate from the scapula and insert into the elbow.
The Tricep 101 – What You Should Know
The tricep is a muscle located on the upper arm’s backside, and its primary function is elbow extension (straightening of the arm).
Unlike the bicep, the tricep has three heads – a medial, long, and lateral one. The medial and lateral heads originate from the humerus and insert into the elbow.
The long head, however, also crosses the elbow joint as it originates from the scapula. Because of that, the long head is also involved in arm adduction (bringing your arms in) and shoulder stability.
The Bicep vs. The Tricep – How Are They Different?
Now that we have a basic understanding of the two muscles, let’s see what the primary differences are:
The most apparent difference between the two muscles is their location. Where the tricep covers the backside of your upper arm, the bicep covers the front.
- Anatomy and Structure
The next significant difference between the two muscles is their anatomy. The tricep has three heads, where the bicep has two. Thanks to their inherent differences in anatomy, location, and structure, the two muscles also differ in their overall size, shape, and functions.
It may come as a surprise to some folks, but the tricep is a more massive muscle, as it makes up roughly two-thirds of the upper arm, where the bicep takes up about a third of the entire volume. So, while most people flex their biceps to show how developed their arms are, the tricep is a more massive muscle.
The last and most significant difference between the bicep and tricep is their functions and how they relate to one another. The two muscles have an agonist-antagonist relationship. Meaning, whenever your bicep shortens, the tricep lengthens and vice-versa.
The bicep primarily serves to flex your elbow (such as during a curl), which causes your tricep to lengthen. Then, as you extend your elbow, the bicep lengthens, and the tricep shortens. When doing an exercise that causes elbow extension (such as tricep cable extensions), your tricep primarily does the work by compressing. Meanwhile, your bicep lengthens.
Final words on the bicep vs. the tricep – how are they different
In simpler terms, the two muscles have opposing functions – if one contracts concentrically, the other has no choice but to lengthen.