Fast Twitch Muscle Physiology and Differentiation

Keith talks about the different qualities and fuel substrates of the two Fast Twitch Fibre Types: the extremely powerful alactic anaerobic Type IIB fibre, which runs off very high-energy creatine phosphate stores within the muscle, with peak power output around 5 to 6 seconds, and produces no acidosis, contrasted with the Type IIA Fast Twitch Glycolytic Fibres, which are less powerful, but are associated with an acidic burden, oxidation of lactate C3H6O3 as a carbohydrate, resulting in the production of CO2 and H2O, generation of H+ ions upstream, and acidosis. Keith then describes the Strength Training Pyramid of Training Intensities, and the specificity of neuro-muscular recruitment, and the best running and non-running exercises to stimulate the alactic system and the IIB fibres, safely, year-round if desired. He also talks about how a specific form of explosive, high power weight training at near-maximal loading aimed at specifically loading the Type IIB fast twitch fibres alactically, has been proven by good research to increase stride length, racing speeds, and running economy in highly trained endurance runners, while dropping their overall aerobic training load by 35%, while showing no measureable gain in VO2 Max or anaerobic threshold. This is just to demonstrate there are many ways of increasing athleticism and relative endurance safely, which can easily be incorporated into the flexible Lydiard training patterns leading to an anaerobic peak on top of a huge aerobic base.

[@bswims]

Hi Keith. Really interesting thanks. How do type 2B fibers make you faster, unless you are running at more than 87% max? How do you get faster at endurance (not flat out)? Cheers