A UNC-Chapel Hill study conducted by the Matthew Gfellar Center studied more than 1,500 former NFL players found that two of the most commonly used ways to estimate head injury risk, years played and playing position, are not actually linked to poorer long-term physical or mental health. Instead, researchers say that directly assessing a player’s concussion history is a more accurate way to understand who may face long-term health challenges.
The research team set out to answer a simple but important question: Do career length or playing position predict long-term health in former NFL athletes? Their findings show they do not. Although these measures are often used as stand-ins for head injury exposure, they didn’t help identify which players experienced worse mental or physical health later in life. The study suggests that future research and potentially future health guidelines in sports should rely on confirmed concussion history rather than assumptions based on position or years in the league.
“It is often thought that certain positions are at higher risk of sustaining concussion, which may be related to shorter playing careers and worse long-term health outcomes, but that’s not what we found,” said Wesley Cole, co-investigator and first author on the paper.
This study is part of the multisite NFL-LONG project and is one of the largest and most detailed examinations of former professional football players to date. Unlike earlier research, the Carolina team along with their collaborators analyzed years played and position together while also accounting for concussion history, sleep, pain and other health factors. This approach provided a clearer view of what truly matters for long-term outcomes.
“When we took concussion history and other health and demographic factors like sleep and pain into account, neither playing position nor years played were linked to poorer long-term mental or physical health outcomes,” said J.D. DeFreese, co-investigator and co-author of the paper.
The research paper is available online in the Current Sports Medicine Reports at: https://journals.lww.com/acsm-csmr/fulltext/2025/11000/neither_american_football_playing_position_nor.6.aspx
Current Sports Medicine Reports
Neither American Football Playing Position Nor Total Years Playing Football Are Associated with Neurobehavioral Health Outcomes: An NFL-LONG Study
24-Nov-2025