PURPOSE: The purpose of this study was to determine the relationship between repetitive head impacts (RHI) and clinical concussion assessments across a season among collegiate football (FB) and women’s soccer (WSOC) players.
METHODS: Fifteen male FB and 23 WSOC players participated in this study. Participants were included if they were medically cleared for unrestricted athletic participation. Participants were tested in a university athletic training room on two occasions: pre-season (PRE) and post-season (POST). The outcome measures consisted of Tandem Gait (TG), Standardized Assessment of Concussion (SAC), Balance Error Scoring System (BESS), King-Devick (KD), Clinical Reaction Time (CRT), and Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). RHI during the season was quantified using the Head Impact Telemetry System (HITS; Simbex, NH) for FB and the Smart Impact Monitor (SIM; Triax Technologies, CT) for WSOC. Independent variables included total number of impacts, average magnitude of peak linear acceleration, cumulative linear exposure, and number of impacts >98g.
RESULTS: Results from direct-entry multiple regression analyses suggest significant associations between RHI and both Visual Memory (R=0.670, F=6.487, p=0.002) and TG (R=0.636, F=3.841, p=0.029) for WSOC and between RHI and KD (R=0.756, F=5.579, p=0.013) for FB, whereby those with greater exposure performed worse. No other regression analyses within or across groups were significant.
CONCLUSIONS: These data suggest that RHI do not represent clinically meaningful changes on a multifaceted and multimodal concussion assessment battery. However, there may be subtle visual/vestibular impairments as observed by the associations between RHI and Visual Memory/TG among WSOC, RHI and KD among FB.