PURPOSE: Assess the potential for training-induced improvement of whole-body reactive agility (WBRA) performance among elite athletes with a history of sport-related concussion (HxSRC).
METHODS: A cohort of 16 elite athletes (25.3 ±5.8 years; 10 males: 69.0 ±3.8 cm, 160.7 ±27.4 kg; 6 females: 63.8 ±2.0 cm, 144.47 ±28.7 kg) representing 5 Olympic sports participated in 12 training sessions over 26 ±9 days. A virtual reality motion analysis system measured whole-body responses to targets presented on the right and left sides of a monitor. A second dual-task (DT) trial simultaneously presented targets on both sides of the monitor, with correct response direction indicated by the center arrow of flanker test displays (<<<<<, >>>>>, <<><<, >><>>). Measures of WBRA included total distance of excursion, reaction time, speed, acceleration, and deceleration. Performance in right versus left directions was calculated for the latter 4 measures, as well as an average of asymmetries (Asym). Performance values were combined to create 3 training phases of 4 sessions each. The association of phase 1 measures with HxSRC status was assessed through ROC analysis. Repeated measures ANOVA was used to assess improvement from phase 1 to phase 3.
RESULTS: Self-reported HxSRC at 3.0 ±2.2 years prior to testing (range: 0.3 - 8.0 years) represented 56% of the cohort (9/16; 5 males, 4 females). Total distance ≥27.3 m for DT demonstrated good discrimination between no SRC (NoSRC) and HxSRC cases (AUC=.714; OR=7.5). A significant DT group X phase interaction effect was evident (P=.038) for total distance, with greater improvement for HxSRC (28.6 ±4.0 to 24.4 ±2.5; SRM=2.06) than NoSRC (25.9 ±1.5 to 24.2 ±1.1; SRM=0.93). Single-task (ST) WBRA Asym ≥13.4% demonstrated good discrimination (AUC=.698; OR=5.0), and thresholds of ≥10% and ≥15% demonstrated remarkable similarity to the results of our previous studies. Significant ST-WBRA Asym reduction was observed (P=.049; SRM=0.57), but the magnitude was similar for HxSRC (15.7 ±4.7% to 12.6 ±2.4%) and NoSRC (12.9 ±3.7% to 10.2 ±2.5%).
CONCLUSIONS: Measures of WBRA may identify subtle impairments in brain network connectivity. The WBRA training appeared to induce a visual-spatial calibration improvement that was greater among HxSRC athletes, which may reduce injury risk.