There are joints in your body that are more unstable than others. Did you know that? Their instability makes them more prone to injury, especially when the muscles, ligaments and tendons surrounding them aren't healthy and strong. Score another point for strength and flexibility training, right?

Last month we showed a little love to our triceps, those muscles on the backs of our arms that often get too little of it. In keeping with the theme of getting to know and appreciate the muscles of our upper body, I wanted to write a little bit about shoulders. 

The "ball" at the top of the bone of your upper arm is actually larger than the "socket" of the joint in which it fits. So, the muscles, tendons and ligaments of the shoulder complex are responsible for keeping the joint stable and preventing dislocation and other injuries. 

It has the largest range of motion of all the joints in your body. The shoulder has only one bony attachment to the rest of your skeletal system, via the clavicle. This, combined with the shallowness of the joint (described above) is responsible for its wide range of motion. It moves laterally away from your body (abduction); it moves forward (flexion); it moves backward (extension); and it rotates laterally and medially. 

You use your shoulder muscles all the time. Anytime you reach overhead, lift and carry something in your arms, rake leaves--do any kind of manual labor really--you are placing demands on that complex structure. That doesn't even take into account any formal shoulder exercises you do in your strength-training routine. Overhead presses, front and lateral raises, upright rows, Arnold presses, planks and incline flyes are just a few examples. 

You see the results of training your shoulders more quickly than other muscles. While there are many differences between our individual bodies and where we carry extra tissue, the shoulder is a place where, universally, there is simply less tissue between the muscle and the skin. So, when you begin training the muscles of the shoulder and they increase in size, you see them relatively early compared to other muscles of the body. They have a nice shape as they get stronger, and the way they taper down your upper arm can make your arm appear smaller. 

Your shoulder is not just one muscle, but many. You've heard the term "rotator cuff," right? That refers to four small muscles that surround the shoulder joint (supraspinatus, subscapularis, infraspinatus and teres minor). They are responsible for holding the head of your humerus bone inside the shoulder joint. You don't see these muscles, but you need them to be as strong and as healthy as they can be. Then there's the deltoid muscle (you can see this one) and the teres major. This is a really short anatomy lesson, I know. But the point is that when you train the shoulder, you aren't just training one muscle, but several. 

I hope one or more of the little tidbits I shared above encourage you to spend some time on your shoulders. As I said in the triceps post, the more we know about our bodies and how interesting and amazing they are, the harder it gets to hate them. Many of us spend an inordinate amount of time criticizing them for not being the size, shape or whatever that we wish they were. What would happen if we shifted even half of that effort into celebrating them?