Yes while I accept what you're saying, it is the only area of the game that teams can really improve on, unlike skill and technique which are much harder to develop(if it's even possible!) when players become adults. I don't understand why it is not used more to maximise teams' performances. I remember reading how Ian Harte would run in the sand and sea in Louth before preseason, just to give him that fitness edge over other players. And before you say it Charlie, I know it didn't help make him any quicker! This sort of training does not need great facilities just hard work on the part of the players.
