The NFL credited a drop in the number of concussion cases this season with advances in helmet technology but players said it could take time to convince all those on the gridiron to reach for the new gear.

Player concussions dropped 17% this season compared to last, reaching a record low amid improvements in helmet safety, the introduction of helmet covers known as guardian caps and changes to the rules governing kickoffs,

NFL medical officials are pointing to players choosing new helmet models as a reason concussions continue to decline. Driving the news: Thirty teams brought the helmets into their locker rooms this season,