- Aug 2020
“Henneman’s size principle” and it provides the basis for why Myo Reps work so well.Evolution is an effective optimizer. If you are wasting energy, you’re dead. That sounds harsh in the modern, comfortable world, but it’s true, and a large part of how our muscles contract. The brain — via the central nervous system — will only contract as few muscles as it takes to get the job done. If you are walking down the street at a moderate pace, only your weakest muscle fibers will activate, not your strongest ones.
Henneman's Size Principle says that motor units are recruitted from small to large as the force required increases.
We use the minimal amount of motor units to get the job done (efficiency). To grow muscles we need to overwork muscles to fatigue, which means doing high intensity or large load exercises.
Excellent video on Myo Reps: https://www.youtube.com/watch?v=R3awPWm97dA