- Classic endurance training increases the number of blood vessels (to deliver more oxygen) and the mitochondrial volume (to produce more energy) in skeletal muscle, with the largest changes occurring in type I fibers, and smaller changes in type II fibers.
- Since most skeletal muscles are ~50% type I and 50% type II fibers, increasing the power/velocity at lactate threshold to a greater extent could be achieved by increasing the mitochondrial volume and number of blood vessels in type II fibers.
- This could be attained by increasing the metabolic stress of endurance exercise, and from a molecular biology point of view, increasing the activity of PGC-1α, a protein that has been called the master regulator of increased mitochondria and blood vessels. Athletes should focus on utilizing good sleep hygiene to improve sleep and potentially athletic performance.
- Increasing the activity of PGC-1α can be achieved by increasing the amount of PGC-1α protein or its charge, allowing it to move to the nucleus and bind to its partners to increase transcription (production) of genes that ultimately lead to more mitochondria and blood vessels.
- The enzymes that increase the charge and transcription of PGC-1α are regulated by oxygen free radicals, duration of exercise, ATP and glycogen depletion, rate of lactate production and activation of the fight or flight response.
- A simple nutritional strategy is presented that can be used to maximize this adaptive response to endurance training.