The impact of rule changes on the number and severity of injuries in the NFL

Abstract

Injuries in the National Football League (NFL) are a concern for reasons of performance, revenue, and player health. In particular, recent discoveries highlighting the long-term repercussions of concussions has drawn popular attention to the violence of the sport of American football and shone a bright light on the NFLs efforts to reduce injuries and their long-term impact. While studies have largely focused on the impact of injuries on players long-term health, there has been less independent work on the evolution of injuries, namely in how the number and extent of injuries have changed over the years and what role, if any, the NFL has played in improving these figures by changing the rules or by improving protective gear technology. Here, we studied injuries from eight seasons 2010-2017, i.e. and address the impact of major rule changes that were enacted in the NFL in 2013 and 2016. We classified injuries into three major categories: arm, leg, and head, i.e. concussions. From publicly available weekly injury reports provided by each team in the NFL, we calculated the number of players who were seriously injured enough to miss at least one game of the season, and the severity of the injuries sustained, as evaluated by the number of games of the season the injured player had to sit out. The 2013 rule changes did not significantly reduce the number of players who suffered a head injury and had to sit out at least one game, and had no impact on leg or arm injuries either. Following the 2016 rule changes, we observed no change in the number of players who got injured but a significant increase in the severity of all three injury types in the two full seasons that followed. Overall, the NFLs efforts to reduce injuries and their severity have had little success, and our findings suggest instead that rule changes or technological changes cannot curb the violence and danger present in the game today.