The temperature inside football helmets during head impact: a five-year study of collegiate football games

Abstract

The objective of this study was to measure in-helmet temperature at the time of impact in a large cohort of football players, as such data can provide new insight to the temperatures helmets should be evaluated at during experimental testing that assess helmet safety. A large cohort of Virginia Tech football players were instrumented with the HIT System (Simbex, Lebanon, NH, USA), which recorded in-helmet temperature and head acceleration for head impacts experienced during 60 games between 2006 and 2010. The average in-helmet temperature at time of impact was 76.4 °F ± 10.1 °F (24.6 °C ± 5.6 °C). In-helmet temperature was strongly correlated to the ambient temperature of the game. Head acceleration resulting from impact varied less than 10% across temperatures, and temperature did not significantly influence head acceleration. These data have implications for the testing conditions used in the laboratory when evaluating the safety of helmets.

Keywords

Impact biomechanics helmet testing concussion brain injury STAR evaluation system head acceleration

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