NFL, NFLPA Sign New Device to Measure Field Conditions

The NFL and the NFL Players Association have mandated the use of a new device to measure field conditions before regular-season games this season, league officials told ESPN.

The development and introduction of what’s known as a “Strike” device is part of a larger effort to create a set of universal guidelines for the league’s 30 playing surfaces, while addressing a contentious issue between owners and players in recent years. Those guidelines, NFL field director Nick Pappas said, are expected to be in place by the 2025 season.

“We’re going to develop our own performance specification document for the NFL field,” Pappas said. “Ultimately, it’s going to be a regulatory document that says, ‘Look, an NFL field should meet these standards.’ Right now, our standards are a little vague, but that’s because we didn’t want to arbitrarily adopt something that might be wrong.”

NFL players have long pushed the league to improve playing surfaces. In 2023, NFLPA executive director Lloyd Howell called on owners to convert the league’s 15 artificial turf surfaces to grass. The league has cited data that shows a relatively small gap in non-contact lower-body injuries on natural and artificial surfaces, and has instead argued that consistency between surfaces is a more realistic goal.

In addition to the Strike, the league will continue to use its Clegg device to measure field hardness before games. NFL rules require Clegg measurements between 50g and 100g for a surface to be approved for play.

The Strike device, designed by the league’s biomechanical partners, will provide a variety of data that Pappas said will allow for a better assessment of field conditions. It will provide a measurement based on two energy measures. The first is restitution, which is how much energy is absorbed by the ground versus what is returned to the player when he steps on it. The second is deformation, which is how much the surface deforms when it comes into contact with the foot.

Only the Clegg reading will be used for compliance during the 2024 season, but the Strike measurements will be incorporated into next season’s guidelines and will likely replace the Clegg in the near future.

“We think (the strike) is more indicative of that initial perforation of the surface or how a spike penetrates the surface and displaces the fill or displaces the sand or the root material,” Pappas said.

“That’s what we think will allow us to better assess what the player is feeling and better measure our domains going forward. Clegg has done great things for us in the initial task of getting us to better standardisation, but there may be some values ​​that are diminishing at this point and we need to go further to better understand our domains.”