Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Helmets and other protective equipment help to reduce injury during athletic activities. For example, football helmets protect a wearer's face with a facemask and reduce head injuries by deflecting and absorbing the force of a blow to the wearer's head. However, repeated and/or severe blows to the head may lead to concussions and may increase the likelihood of developing conditions like chronic traumatic encephalopathy (CTE).