In chapter 1, Kenny and Andy dive deep into the science and applications of physiological adaptation. Research has shown that people can significantly change the composition of their muscle fibers and the magnitude of such changes can be shockingly high. Human beings can alter their physiology with exercise and nutrition far more than previously believed.
Enjoy!
Kenny and Andy
P.S. Before you dive in, make sure to check out volume 1 prologue episode: Body of Knowledge — Prologue — Origin Story.
Deep adaptations
In this chapter, Body of Knowledge addresses the fact that physiology can actually be built depending on the activity of the athlete. The days of labeling an athlete as having “fast” or “slow” twitch fibers are nearing the end as we understand more about how fibers can be conditioned and trained to actually change fiber type.
Andy helps us to understand the history and evolution of how we understand the function of muscles and the differences between fiber types from the early 1700’s until present day. The future of this knowledge is to determine why certain individuals can handle more volume than others, or why certain people can recover more quickly, and ultimately increase the efficacy of personalized training programs.
“As a gym owner, one of the things I am continually trying to anchor is the improvement of people’s quality of life.” — Kenny Kane
Key Takeaways
- In 1954, for the first time in history, we were able to view the exact mechanics of muscle fibers — We were able to explain in improved terms that muscles are not filled with air (as many speculated up to this point), but rather there was a signal from the brain, with the involvement of a respiratory process, that allowed muscle fibers to stack on top of one another, causing the muscle to grow taller.
- The types of muscle fibers (fast and slow) are not necessarily determined by genetics and actually have a high degree of plasticity.
- Humans have a few types of muscle fibers: Slow, fast, ultra-fast, and everywhere in between — The ratio of fast vs. slow depends on the activities of the individual. Marathon runners will have more slow twitch while olympic weightlifters will have more fast twitch.
- Hybrid muscle fibers — A single cell can be partially fast and partially slow. Inactive individuals will typically have more “hybrid” fibers, which will almost immediately specialize into “fast” or “slow” when they are exposed to movement.
- Responders vs. non-responders — Based on fiber type and the molecules within an individual’s muscle fibers, certain people can put on muscle more easily than others exposed to the same stimulus. Others, conversely can be better suited to increase strength.
“If you compare your glute and my glute, it’s almost guaranteed that the percentage of fast versus slow in your glute is going to differ in mine.” — Dr. Andy Galpin
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