Though it’s a holiday weekend for some, it’s a working weekend for the rookies of four NFL teams.

The Cardinals, Dolphins and 49ers kick off their rookie minicamps on Friday, with the Chiefs commencing their rookie workouts on Saturday. The practices will span three days for all four clubs.

According to the collective bargaining agreement between NFL owners and players, minicamp practices are non-contact workouts. Though players can wear helmets, they cannot wear pads.