Joint Prevalence of Sitting Time and Leisure-Time Physical Activity Among US Adults, 2015-2016

differentially affect activities during different types of plays during competitions and hence would not bias this analysis.Confounding by player or game characteristics changing over time and surveillance bias are possible.The action taken by Ivy League leadership based on epidemiologic evidence demonstrates how targeted policy changes can reduce sport-related concussion.Although these results may not generalize beyond the Ivy League, they may inform the NCAA as it considers adjusting the kickoff rules in football in all collegiate conferences.