Definition: Skeletal muscle fibers characterized by their expression of the Type II MYOSIN HEAVY CHAIN isoforms which have high ATPase activity and effect several other functional properties - shortening velocity, power output, rate of tension redevelopment. Several fast types have been identified.
Other names White Muscle Fibers; White Muscle Fiber; Muscle Fibers, Fast Twitch; Muscle Fiber, White; Muscle Fiber, Intermediate; Muscle Fiber, Fast-Twitch; Intermediate Muscle Fibers; Intermediate Muscle Fiber; Fibers, White Muscle; Fibers, Intermediate Muscle; Fibers, Fast-Twitch Muscle; Fiber, White Muscle; Fiber, Intermediate Muscle; Fiber, Fast-Twitch Muscle; Fast-Twitch Muscle Fibers; Fast-Twitch Muscle Fiber; Muscle Fibers, White; Muscle Fibers, Type II; Muscle Fibers, Intermediate