the way the impacts happen. in rugby contact rarely happens with players moving in directly opposite directions, usually its at an angle that reduces the impact,and seldom involves the head.
football is the opposite, especially with runs up the middle , receivers cutting across the middle of the field, and the smaller, but constant, impacts experienced by the linemen on both sides of the ball.
football is the opposite, especially with runs up the middle , receivers cutting across the middle of the field, and the smaller, but constant, impacts experienced by the linemen on both sides of the ball.