Patterns of head impact exposure in men's and women's collegiate club water polo

Objectives: Recent reports have demonstrated a risk of concussion and subconcussive head impacts in collegiate varsity and international elite water polo. We sought to characterize patterns of head impact exposure at the collegiate club level of water polo. Design: Prospective cohort study. Methods: Head impact sensors (SIM-G, Triax Technologies) were worn by men's (n = 16) and women's (n = 15) collegiate club water polo players during 11 games. Peak linear acceleration (PLA) and peak rotational acceleration (PRA) of head impacts were recorded by the sensors. Two streams of competition video were used to verify and describe the nature of head impacts. Results: Men's players sustained 52 verified head impacts of magnitude 39.7 ± 16.3 g PLA and 5.2 ± 3.2 krad/s² PRA, and women's players sustained 43 verified head impacts of magnitude 33.7 ± 12.6 g PLA and 4.0 ± 2.8 krad/s² PRA. Impacts sustained by men had greater PLA than those sustained by women (p = .045). Athletes were impacted most frequently at the offensive center position, to the back of the head, and by an opponent's torso or limb. Conclusions: Our cohort of male and female athletes sustained relatively infrequent head impacts during water polo competitions played at the collegiate club level. The amount of head impact exposure in our cohort was dependent on player position, with offensive centers prone to sustaining the most impacts. Head impact sensors are subject to large amounts of false positives and should be used in conjunction with video recordings to verify the validity of impact data.