Darcy Broadbent
- Apr 19, 2020
- 2 min read

Muscle 101-The Pecs

Is This An Important Muscle?

Ya...this is an important muscle to know about because it can lead to all kinds of problems if you don’t take care of it. It’s a muscle that can get over-active (or “tight” is a good word too) due to certain activities you take part in each day such as sitting at a desk, driving, swimming a lot (yes, really…swimmers get tight chest muscles and it affects their posture---it’s a thing so go look it up)

Ok, So Where Exactly Is It Located?

The chest muscle—or Pectoralis Major as the textbooks will call it—attaches to your clavicle bone, your sternum and the bone in your upper arm (called the Humerus---funny eh?) In order for the muscle (or any muscle) to create movement, it has to cross a joint. According to the picture, you can see that the chest muscle crosses the shoulder joint so that means it will create movement at the shoulder.

I’m With You So Far…But What Does This Muscle Do?

The chest muscle does 3 things. When the muscle is activated (Activated? What language do you speak? Think of “activated” as flexing your muscle) it will perform 3 different actions. The pictures below will give you an illustration but to put the pictures to words, the chest muscle will flex the shoulder, adduct the shoulder and internally rotate the shoulder. It’s kind of a busy muscle! And if that wasn’t enough, it also helps stabilize the shoulder.

Adduction Rotation Flexion

It Sounds Like An Important Muscle, I should Exercise It A Lot

Well, not really. You now know that the pecs will adduct and internally rotate the shoulders. This is pretty much the same action you perform when you sit at a desk all day, drive in your car a lot or slouch over your dinner plate. So before you rush to go do more bench presses, understand that your pecs may already be over-worked.

Over-Worked? I Hate Being Overworked

I know. I’m not saying never to do chest exercises but I want you to know that it’s all about balance. Nobody will know if you have over-active chest muscles without a good movement assessment but if you do, make sure a good chest stretching routine is part of your fitness. And if you do a chest exercise, be sure to balance it out with 1 or 2 back (pulling) exercises.

Do You Have One Last Thing?

Yes, one last thing. Be sure to practice good posture when sitting at your desk. Back straight, head up, shoulders back. Why not set a reminder on your phone every hour to do a posture check? Take notice how you are sitting (or standing or walking) and adjust your posture.

Do you like free? Why not contact me for a free movement assessment. It doesn’t take long and you will come away with knowing exactly what muscular imbalances you have and how to correct them.