250 ‒ Training principles for longevity | Andy Galpin, Ph.D. (PART II)

Hypertrophy Types

Andy Galpin explains the two main types of muscle hypertrophy: contractile and sarcoplasmic. Contractile hypertrophy involves increasing proteins on myosin and actin, leading to muscle growth, while sarcoplasmic hypertrophy is characterized by fluid retention within the muscle cells. This distinction is crucial for understanding how different training methods impact muscle size and strength.

Contractile hypertrophy happens as a result of increasing proteins on those myosin and actin.

--- Andy Galpin

Peter Attia and Andy discuss how endurance athletes often exhibit fiber type-specific hypertrophy, with slow-twitch fibers becoming exceptionally large due to their training regimens 1 2.

   

Hypertrophy Mechanics

Understanding the mechanics behind muscle hypertrophy is essential for optimizing training. Andy describes how muscle fibers, composed of actin and myosin, contract and expand, leading to muscle growth. This process, known as lattice spacing, ensures optimal spacing between proteins for effective contraction.

The biggest explanation for why muscle increases in its diameter is exactly that you've put more proteins in the contractile units.

--- Andy Galpin

He emphasizes that early in one's training career, muscle growth and strength gains are closely linked, but they diverge as training progresses 3 4.

   

Training Methods

Different training methods significantly impact muscle hypertrophy and overall fitness. Andy highlights the importance of practicing perfect repetition and working to technical failure rather than focusing solely on the number of reps. This approach helps in maintaining proper form and preventing injuries.

You want to practice perfect repetition. Instead of going to an RPE, I'm going to go to technical failure.

--- Andy Galpin

He also discusses the benefits of power training, which can be done daily with low fatigue, making it suitable for various athletes 5 6.