Mapping the acute trajectory of sport-related concussion outcomes across symptoms, cognition, and blood biomarkers

Abstract

Sport-related concussion (SRC) and its potential neurological sequela represent an emerging global health concern, requiring improved recovery management and strategies for return-to-play (RTP) to enhance brain health in athletes. Given the dynamic and multifaceted nature of SRC recovery, the purpose of this review is to synthesize existing literature on post-SRC outcomes in adult athletes, and to outline the temporal trajectories of key recovery indicators (symptoms, cognitive function, blood biomarkers) across distinct recovery phases until resolution. In the acute phase of SRC (first 48 ​h), symptom scores and brain damage markers peaked immediately, while cognitive impairments and neuroinflammation emerged with a slight delay. Following the initial rise, brain damage marker concentrations rapidly dropped below baseline levels at approximately 48 ​h following SRC injury. During the early recovery phase, neuroinflammation and most cognitive alterations resolved after 3–5 days, though symptom burden and attention deficits persisted for up to 7 days. Despite prolonged alterations reported in some individuals, recovery markers typically returned to pre-injury levels in the transition phase (≤ 2 weeks), though mild attention deficits were detected up to 3 weeks, and TNF-α concentrations remained elevated throughout late recovery (> 2 weeks). These results reveal distinct temporal discrepancies across recovery markers and emphasize that physiological disturbances can outlast symptom resolution, underscoring the need for both multimodal assessments and appropriately timed evaluations to accurately track recovery progression. Incorporating structured follow-ups at key time points, particularly beyond symptom resolution, may improve RTP decision-making and reduce the risk of premature return and long-term neurological consequences.