Fatigue in Soccer: Acute and Residual Responses

Fatigue in soccer can manifest both transiently during a game and progressively, leading to diminished end-game performance, particularly in terms of the ability to execute repeated high-intensity actions. The origins of transient and end-game fatigue are diverse, stemming from various sources such as acute disruptions in the intracellular metabolic and ionic environment, substantial substrate depletion, muscle damage, alterations in core temperature, and fluctuations in hydration status, among others. Importantly, the development of fatigue can exhibit significant variability between individuals. Furthermore, the postgame recovery process may extend over a prolonged period and encompass structural, metabolic, and/or inflammatory/immunological responses. This recovery is likely influenced by both extrinsic factors of importance for the load imposed on a player and intrinsic factors of importance for how well the player tolerates the load endured. Post-game physiological alterations can be acute following a single game or accrue over extended periods, particularly during fixture congestion or a lengthy in-season period characterized by limited opportunities for rest.