NFL tight end Julius Thomas is hanging up his cleats for a doctorate degree.
Thomas is retiring from professional football to pursue a Ph.D in psychology, the 30-year-old announced in the Players' Tribune on Friday.
Thomas said he will focus his doctorate on "investigating the effects of contact sports on brain trauma and neurobehavioral performance." He will also participate in research to "identify early warning signs of brain disease."
He said he felt particularly called to the study of CTE: "I knew I wanted to help and knew that this would be a great way to help football players, to be that person who could help them understand what we all are at risk of.