This chapter frames recovery as an evidence-based, multiscale biological process that links short-term performance restoration to longer-term adaptation, rather than a single rested versus tired state. It explains why recovery time courses differ across exercise types and physiological levels (metabolic, neuromuscular, microvascular, inflammatory, and perceptual), and why a single marker rarely captures the dominant limiter of readiness. It then details how unaccustomed or high-strain loading can disrupt sarcomeres and excitation–contraction coupling, initiating repair and remodeling cascades that may transiently impair force, range of motion, and function. The chapter connects inflammatory signaling to tissue repair, emphasizing regulated leukocyte responses and active resolution as prerequisites for effective regeneration and training adaptation. Finally, it shows how symptoms (e.g., DOMS, perceived tightness) and mechanical constructs (e.g., tone, stiffness) emerge from interacting neural, connective-tissue, and fluid-dynamic mechanisms, informing what to measure, and how to interpret it, in real athletes.