Believe it or not we still don’t have a complete picture of how muscles grow. Brad Pilon has recently put together some research on a new theory that might help explain how muscles grow and why we can’t continue to grow indefinitely.
In general the theory is about chronic vs acute inflammation. Namely, acute intermittent inflammation from working out is good and helps stimulate muscle growth…but chronic inflammation from stress, infection, or overeating and obesity can destroy your ability to develop muscle.
Working out with weights produces a short term acute inflammatory response in the muscle. Basically the muscle is changed/damaged and then various metabolic changes happen and cells, hormones, and other factors enter the muscle cell to repair/remodel the muscle in response to the workout.
Once the repair and remodeling has taken place the extra material and cells leave the muscle cell.
This is analogous to a normal inflammatory immune response in any other tissue of your body.
The point is that it’s a short term transient change that comes and goes with each workout.
Chronic inflammation from infection, or over stress, or overeating may actually inhibit the ability of your muscle to react and grow in response to working out.
This theory might also provide the proof that “bulking up” will not work (without steroids) because overeating causes a chronic inflammation and ruins the acute inflammatory response.
Brad talks about this in a recent podcast here –> Inflammation Theory of Muscle Growth
He has a full presentation at this website: Inflammation Theory of Muscle Growth