Biocore Study on NFL Preseason Practices

A new study released in July of 2025 offers deeper insight into the impact of Guardian Caps in the NFL. Biocore, an independent biomechanics lab, conducted the research and is the same group responsible for the NFL’s annual helmet performance testing. Using data from the NFL’s Injury Surveillance System, researchers analyzed concussion rates during preseason practices from 2018 through 2019 and 2021 through 2023. They specifically compared data before and after the NFL began requiring certain position groups to wear Guardian Caps in practices starting in 2022.

The Guardian Cap NXT was associated with a 54% to 62% reduction in the overall incidence of NFL practice concussions across all environmental factors.

*The NFL’s conclusion is based on a qualified study that evaluated Guardian Caps alongside additional protective measures, which collectively contributed to a reduction in concussions.

53% Decrease in Concussions with Guardian Caps

Teams required to wear Caps saw concussion counts and rates drop significantly compared to non-required groups.

42% Increase in Concussions without Guardian Caps

Teams required to wear Caps saw significantly fewer concussions than teams that weren’t required to wear them, across most inquiry sources and helmet-shell involvement.