The human body is not the same on both sides.
Look at the picture above. This is a snapshot of the diaphragm. You are looking down into the ribcage. The bottom of the picture is the front of this person's body. The top of the picture is the back.
If you're not just breezing through this article, just stop for a second and look at this picture. Pretend it's the picture game we used to play as kids where we would get two seemingly identical pictures and would have to pick out the differences between the two. Draw an imaginary line down the middle of that picture and start the game.
What do you see? What is different on the right side than the left.
This is what I see...
- Right side looks way bigger
- Right side goes further back
- Left side just looks weaker (less muscular fibers)
- Left side looks flatter
- The aorta is definitely more on the left side
- The curve of the right ribs is definitely different than the left
I think it's safe to say, that at least from this one picture, the right diaphragm looks to be stronger than the left.
We also know that our internal organs are not symmetrically arranged.
The right side of the body is home to the liver and the liver is huge.
The heart sits on the left side.
The liver sits underneath the diaphragm making the right side sit a bit higher, which causes the muscle fibers to shorten on the right.
The heart sits on top of the left diaphragm which depresses that diaphragm and lengthens those muscle fibers.
We all know that shortening muscle fibers makes it easier to contract a muscle and lengthening them makes it harder. It's a whole lot easier to bicep curl a ton of weight if I am only going halfway down.
We could also mention the differences between the left side and right side of the brain that throws a greater bias onto the right side of the body or the fact that we have three lobes of lung on the right and only two on the left but that's really just icing on the cake at this point.
Everyday you take upwards of 20,000 breaths. This means that asymmetrical diaphragm is going to contract upwards of 20,000 times per day. At this point, it should be easy for you to realize how an imbalance is going to form if this isn't managed.
During every breath, there will be a slight twist over to the right side of the body and slowly, over time, the right side will grow dominant as the left side grows weak.
When you do bilateral exercises in the weight room (squat, deadlift, bench etc.) you are expecting to have an even, 50/50 split between the left and right side. But with an asymmetrical design and an already heavily biased right to left side, is a 50/50 split even possible? It simply is not. With every bilateral rep you do, you are driving yourself further into that dysfunction.
Our bodies operate through gait mechanics. Meaning, the processes of our body are designed to function as the body shifts from right side to left and back.
Considering all of these FACTS, I do not use bilateral exercises...EVER.
Now, everyone is dealt a different hand of cards. I do believe that situations exist where bilateral exercises are appropriate but I have organized my business to avoid those situations because I believe unilateral exercises are preferable 100% of the time when training for optimal health or classic sport performance (obviously excluding sports like strongman, powerlifting, etc.).
Your next step will be to learn the pillars of great single leg stance and begin to design your workout programs around this concept.
If you want to learn more about this concept and all of the branches that make up this entire training model, check out the 4A Health Club. Every month I teach a brand new course on a wide range of strength and conditioning topics and all members get access to a private discussion board to discuss all things S&C. All for the cost of a burrito from Chipotle. Click the link below to learn more.