@article{ref1,
title="Head impact exposure in youth football: elementary school ages 7-8 years and the effect of returning players",
journal="Clinical journal of sport medicine",
year="2013",
author="Young, Tyler J. and Daniel, Ray W. and Rowson, Steven and Duma, Stefan M.",
volume="24",
number="5",
pages="416-421",
abstract="OBJECTIVE:: To provide data describing the head impact exposure of 7- to 8-year-old football players. DESIGN:: Head impact data were collected from 19 players over the course of 2 seasons using helmet-mounted accelerometer arrays. SETTING:: Data were collected from 2 youth football teams in Blacksburg, VA, spanning 2 seasons. PARTICIPANTS:: A total of 19 youth football players aged 7-8 years. INTERVENTIONS:: None. Independent variables were the type of session (practice or game) and the player's experience. MAIN OUTCOME MEASURES:: Head impact frequency, acceleration magnitude, and impact location for games, practices, and the season as a whole were measured. RESULTS:: The average instrumented player sustained 9 ± 6 impacts per practice, 11 ± 11 impacts per game, and 161 ± 111 impacts per season. The average instrumented player had a median impact of 16 ± 2 g and 686 ± 169 rad/s and a 95th percentile impact of 38 ± 13 g and 2052 ± 664 rad/s throughout a season. Impacts of 40 g or greater tended to occur more frequently in practices than in games, and practices had a significantly higher 95th percentile impact magnitude than games (P = 0.023). Returning players had significantly more impacts than first time players (P = 0.007). CONCLUSIONS:: These data are a further step toward developing effective strategies to reduce the incidence of concussion in youth football and have applications toward youth-specific football helmet designs.  Keywords: American football; <p /> <p>Language: en</p>",
language="en",
issn="1050-642X",
doi="10.1097/JSM.0000000000000055",
url="http://dx.doi.org/10.1097/JSM.0000000000000055"
}