Muscle Fiber Types Explained: Type 1, Type 2a, Type 2x | Muscle Physiology and Training Adaptations

Muscle Fiber Types Explained: Type 1 vs. Type 2a vs. Type 2x Type 1 -Slow Twitch (slow twitch speed/ slow rate of force development) Small, red Recruited first in response to action potential Slow nerve conduction HIGHLY fatigue resistant (oxidative) good for endurance – high aerobic enzyme content Low Myosin ATPase (low contraction speed) Low power HIGH capillary & mitochondrial density Cross country, marathon Type IIa Medium, white/red Larger motor units Fast contract/relax speed and nerve conduction velocity, intermediate power More anaerobic enzyme content Intermediate capillary and mitochondrial density Low myoglobin Type IIx Largest motor units Largest diameter fiber, white High recruitment threshold Fast conduction and contraction Low fatigue resistance/ endurance High force and power Low capillary / mitochondrial density Large fibers Sprint, weightlifting Studying for the CSCS Exam? Check out the Strength and Conditioning Study Course: https://www.themovementsystem.com/str... 👇🏽Click here to Join a Facebook Strength and Conditioning Study Group!   / 2415992685342170   Comment below if you have any questions! 0:00 0:06 Intro 0:29 Muscle Structure 1:05 Motor Units and Mosaic Distribution 2:15 Size Principle 3:30 Type I Fibers 5:59 Type IIa Fibers 8:52 Type IIx Fibers 10:46 Muscular Adaptations 12:00 Detraining 13:20 Muscle Fiber Hypertrophy 14:20 Myosin Isoform ✅ Let’s Connect: 📱 Instagram: @themovementsystem