Penn State Program Tries to Prevent Concussions by Examining Surfaces
April 15, 2014 in Articles
What does the hardness of the football field have to do with concussions?
According to a recent post in USA Football’s “From the Field” blog, field density plays a sizable factor in head injuries. In fact, Penn State’s Center for Sports Surface Research reported that 10 percent of concussions come from how hard the ground — or the artificial turf — is on a football field.
A properly maintained playing surface can help reduce head injury risk. Whether natural or synthetic turf, field management practices directly affect field hardness and, in turn, risk of head injury.
As a result, monitoring field hardness is key. In fact, the NFL now requires field managers to measure surface hardness before every game.
Surface hardness is measured by dropping a weight — often referred to as a missile — from a fixed height onto the playing surface. The missile contains an accelerometer that measures how fast the missile stops once it hits the surface. A numerical value (referred to as Gmax) is then generated.
A high Gmax value indicates the missile stopped quickly. Think of this as dropping the missile onto concrete. If the missile was dropped onto a pillow, it would take a longer time for the missile to stop and the softer surface would produce a lower Gmax value.
The NFL field testing program requires playing surface hardness of both natural and synthetic turf fields to be measured with the Clegg Impact Tester. Fields must be tested in multiple locations prior to every game and must be below 100 Gmax.
The Center has a separate device for measuring the hardness of artificial surfaces.