Typically, the first few days of training camp are reserved for work without pads on as the team goes through a ramp up period, taking a few days to acclimate to playing football again after some time off whilst limiting the number of collisions that occur outside of actual NFL games.
Still, when you are dealing with grown men running full speed in a collision sport, it can be hard to lay off the trigger at times. This is exactly what happened with DB Damontae Kazee yesterday at practice when he came over the middle and laid a big hit on rookie WR Calvin Austin III.