The National Football League (NFL) hired SRI in the mid-1980s for a multidisciplinary study of measures to reduce the number and severity of injuries to professional football players.
The study began with analysis of the numbers, types, and causes of injuries to players. SRI proposed, for the first time, a gradation in the severity of injuries. This system gave the NFL a way to quantitatively assess which injuries needed the most attention, and the causes that led to the prevalence of each.
SRI then proposed changes such as better player conditioning, improved playing surfaces, better equipment (especially helmet design), and rule changes. To gauge the effects of various artificial turfs, SRI proposed a “punishment index”—an approach that factored in the effect of cleat size and length on injuries on various surfaces.
SRI was involved in league expansion and movement as well. In specific studies for Commissioner Pete Rozelle, SRI recommended expansions for Seattle and Tampa Bay in 1976 and for the Baltimore Colts to transfer to Indianapolis in 1984.