The concept of "muscle memory" refers to the phenomenon where previously trained muscles can regain strength and size more quickly after a period of inactivity. This occurs because the body retains cellular adaptations made during earlier training, allowing for faster reconditioning when training resumes. Muscle memory signifies that neural pathways and muscle fibers have been "primed" for performance again. This process benefits those who may temporarily stop exercising, enabling them to return to their previous levels more efficiently.