Head Acceleration Magnitude in Sport-Related Concussive Impacts: A Systematic Review and Meta-analysis.

Abstract

Sport-related concussion (SRC) is a common and complex injury in athletic populations. Linear head acceleration (LHA) and rotational head acceleration (RHA) are key biomechanical factors believed to contribute to SRC, each through distinct mechanisms. Evaluating head impact magnitudes across different sports, athlete populations, and measurement methods is essential for advancing SRC injury prevention and risk assessment. We aimed to examine linear and rotational head acceleration magnitudes associated with SRC impacts in athletes participating in team sports across all ages and both sexes. We conducted a systematic review and meta-analysis adhering to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. We searched three databases (MEDLINE, Scopus, SPORTDiscus) until 4 September, 2024, and the literature search was updated on the 10 November, 2025. Observational and experimental studies reporting peak LHA and/or RHA during SRC impacts in team sport athletes were included. Data were extracted on study characteristics, instrumentation, and head impact magnitudes. The risk of bias was assessed using the National Institutes of Health Quality Assessment Tool, and the certainty of the evidence was evaluated using GRADE. Random-effects meta-analyses were conducted to compare SRC and non-concussive impacts, and subgroup analyses were performed by sport type, age group, sex, session type, and instrumentation type, reporting standardized mean difference and mean difference. Between-group differences were assessed using Q_b statistics, and heterogeneity was evaluated using the I² statistics. Sensitivity and publication bias analyses were also performed. Data from 30 articles representing 3262 athletes (12% female) were included. Sport-related concussion impacts produced significantly greater head acceleration magnitudes than non-concussive impacts, with large differences for both LHA (69.6 g vs 25.3 g; standardized mean difference = 2.42; 95% confidence interval 1.73-3.12) and RHA (4931 rad/s² vs. 1966 rad/s²; standardized mean difference = 1.99; 95% confidence interval 1.17-2.81). For SRC impacts, subgroup analyses revealed significant differences across sports (p < 0.001), age groups (LHA only, p = 0.01), sexes (LHA only, p < 0.001), and instrumentation types (LHA p < 0.001; RHA p = 0.02). The highest LHA values were observed in American Football (83.2 g), while the highest RHA values were recorded in rugby (7627 rad/s²). Higher LHA values were recorded for male athletes (78.2 g) compared with female athletes (44.2 g), and for high school athletes (88.3 g) compared with youth (61.4 g) and adult athletes (72.2 g). Helmet-mounted sensors recorded the highest LHA (79.0 g), and skin patches recorded the highest RHA (6938 rad/s²). No significant differences were found between games and practices. In team sports, SRC impacts are associated with significantly higher LHA and RHA than non-concussive impacts. The observed overlap and contextual variability in head acceleration magnitudes highlight the importance of considering individual-specific and context-specific interpretation in SRC risk assessment and provide a foundation for improving head impact monitoring, injury prevention strategies, and athlete safety. PROSPERO CRD42024584070.