The NFL Players Association (NFLPA) has filed a grievance against the league and its clubs over the use of sleep monitoring devices, according to USA Today.

The collective bargaining agreement allows the NFL to require players to wear sensors and other tracking devices during games and practices to collect performance, medical and safety-related information, as long as the NFLPA gives prior consent. The union argues the use of such technology outside of games and practice violates the CBA.

“It has come to our attention that several Clubs are currently using or have used sensors to monitor players’ sleep,” union executive director DeMaurice Smith wrote in his memo to players.

“Because the use of such technology occurs outside of games and practice, we believe such use violates the Collective Bargaining Agreement. Based on this information, the NFLPA has filed a grievance against the NFL and all 32 Clubs seeking an order compelling the NFL and its member clubs to immediately cease and desist from using unapproved sensor devices on players, unless or until such use is approved by the NFLPA.

View the full story at www.usatoday.com