The NFL owners have passed a rule that makes it mandatory for players to wear knee and thigh pads starting in 2013 according to Adam Schefter of ESPN. As written earlier, the NFL Players Association is opposed to the requirement that hight and knee pads be mandatory and could file a grievance saying these changes weren't bargained for. Many players are opposed to wearing thigh or knee pads for a reasons including comfort and interference with players speed. NFL Competition Committee Chairman Rich McKay said the league sees no downside to requiring pads and that It only makes the game safer. Source: The Redzone