Rate of recruitment of muscle fibers

The fiber recruitment level describes how many muscle fibers of a muscles are actually activated during a movement or load. The higher the intensity of an exercise or the required force, the more muscle fibers are recruited. This is closely related to the central nervous system and intramuscular coordination.

A high recruitment rate of fibers is crucial for maximum performance and progress in strength training. With regular training, especially through exercises performed close to muscle failure, the ability to recruit muscle fibers can be improved.