Didn’t play organized football but was on the HS wrestling team. Shark’s bait was the most demanding drill. Six guys per pod, first one gets each of the other five for a minute each with no break. Then you get each of the other five for a minute each when it was your turn. If you were a real hard rock you’d volunteer to go last and you’d also pick a pod with bigger guys.
But then again everybody knows that wrestlers are tougher than football players.