Pec Training For Newbies

Anatomy

The main functions you need to be familiar with are,

Shoulder Horizontal Adduction

Shoulder Horizontal Adduction

Shoulder Horizontal Flexion

Shoulder Horizontal Flexion

It may be hard to see at first, but the difference between the two is the orientation of the shoulder joint.

Adduction of the shoulder requires external rotation of the joint.

Flexion of the shoulder requires internal rotation of the joint. 

To know if your shoulders are internally or externally rotated, put your arms out directly in front of you. Now point your elbows toward the floor. In this position, your shoulders are externally rotated.
Now, point your elbows out to the side. In this position, your shoulders are in a position of internal rotation.

Line of Resistance + Muscle Fiber Direction

Now that we’ve got the anatomy out of the way we can talk a little about biomechanics. Don’t worry, I’m going to keep things as short and sweet as possible.

The first concept you need to understand is Line of Resistance (LoR). LoR refers to the direction from which the resistance is coming.

For example, if you are doing a free weight exercise (dumbbell or barbell exercises) then the line of resistance is straight down, because of gravity. If doing a cable exercise, then the line of resistance is the cable itself.

If you’d like to learn more about line of resistance and its applications, click HERE

Another consideration when choosing an exercise is the direction in which the muscle fibers travel. Muscles contract directly in line with their fiber direction. If possible, try to match the line of resistance with the direction in which the muscle fibers travel.

By looking at the pectoralis major, we can see that each head's fibers go in a different direction.

The upper fibers travel at an upward angle, and the middle and lower fibers are oriented, mostly, at a slightly downward angle.

So, to build the upper pecs, we need to match that slightly upward angle. To build the rest of the pecs, a slightly downward pressing angle is necessary.

Not only does pressing from a slight decline and incline make sense from a biomechanical and anatomical perspective, but research has provided evidence.

Click HERE and HERE for said evidence.

Yes, your pecs will develop more quickly using the aforementioned techniques. But, your shoulders are in a more vulnerable position while internally rotated. Retracting your shoulder blades will help protect your shoulders (more on that in the exercise selection section). But, if you get injured, you can’t build your pecs at all, so be careful.

I, as well as many others I know, internally rotate the shoulders during pec exercises and have no issues.

Also, to further drive home the concept of placing a muscle opposite the line of resistance, I held off on telling you the other function that all three heads have in common, which is Medial Rotation.

Medial Rotation refers to the act of rotating your shoulder joint toward the midline of your body. In other words, bringing your elbows from pointing to the floor, to pointing out to the side.

By medially rotating your shoulders during a chest exercise, you are shifting the line of resistance to be directly opposite the majority of your pec fibers. 

Muscle Function + Line of Resistance + Fiber Angle = Good Exercise

How many reps and sets should you do?

Not only do your muscle’s fibers travel in a particular direction, but they also vary in type. There are many kinds of muscle fiber types (depending on the physiology book you’re reading), but there are only two that you need to know.

Type I: Otherwise known as slow twitch muscle fibers. They have this name because they twitch, or move, relatively slowly. Type I fibers expend energy and fatigue, slowly.

The perfect example of a slow twitch dominant muscle is the calves. Think about it like this, if your calves fatigued quickly, would you be able to walk for extended periods of time?

The calves having mostly slow twitch muscle fibers is a functional necessity.

Type II: Otherwise known as fast twitch muscle fibers. Fast twitch fibers expend energy and fatigue, quickly. The triceps and biceps are fast twitch dominant.

Another good way to grasp the fiber type concept is to compare them with running events. Slow twitch fibers are the long distance runners of your body, and fast twitch fibers are the sprinters.

Luckily for us, fiber type distribution in humans has been studied quite a bit. Otherwise, we’d have to pull out chunks of our muscles, freeze them with nitrogen, and examine them under a microscope.

Research shows the pecs are a predominately fast twitch muscle. Therefore, you should train your chest with short, explosive, heavy bouts of exercise. Fewer amounts of sets (2-6) and reps (1-6), in comparison to slow twitch dominant muscles, are necessary to make the pecs grow.

Frequency (How often should you train your chest?)

I will say, that training a muscle more often, seems to lead to greater growth.

There was a study conducted called the Norwegian Frequency Project. The researchers compared elite powerlifters who trained three times a week, and six times a week. At the end of the study, the six times per week group grew more muscle and strength.

The Norwegian Frequency Project has not been published in an academic journal. However, a statistician took a magnifying glass to the study and found that the Norwegian Frequency Project is rock solid

Read More: A Stats Exercise With The Norwegian Frequency Project

So, how often should you train your chest? 

Train your pecs as often as possible.

“But don’t I need to let the muscle recover for it to grow?”

Yes, you do. However, after weight training, muscles are fully recovered within 24 hours. So, as long as you’re eating enough, and getting a proper amount of sleep, you can train your chest every day.

Please, make sure to train your other muscles as well……please.