10 Influence of playing rugby on long-term brain health following retirement: an updated systematic review and meta-analysis

Introduction Physical activity has been shown to enhance cognitive reserve. Concussions are a concern in contact sports, with potential long-term effects on brain health. We examine the impact of concussion exposure on cognitive performance in retired rugby players.Materials and Methods A systematic search of six databases from inception to April 2025 identified cross-sectional studies assessing cognitive functioning in retired players via at least one cognitive assessment. Data extraction was performed using Strengthening and Reporting of Observational Studies in Epidemiology guidelines. Methodological quality was assessed using the Downs and Black quality tool.Results Thirteen studies of overall ‘moderate’ methodological quality were reviewed, comprising 1199 retired rugby players (female n = 159; mean age 38–70 years). Meta-analysis of eight studies (n=680 retired rugby players, n=366 controls) demonstrated that retired players performed significantly worse on cognitive measures (SMD=-0.2541, CI =-0.482 to 0.0264, p=0.029). Moderate heterogeneity was detected (I 2=58%). Subgroup analyses controlling for age revealed no significant differences between retired players and controls (p>0.05). When controlling for variation in cognitive assessments, retired players performed significantly worse than controls, with no heterogeneity (SMD=-0.353, CI =-0.509 to -0.197, p