Manchester United boss Louis van Gaal says he doesn't understand managers prowling the technical area during games.

Van Gaal does not see the point in ranting and raving on the touchline.

"I have never had a fight," he said. "I only use my voice, never my hands or something like that."

So why do other managers scream at their players, officials and rival managers?

"You have to ask them," he replied. "I don't have the idea that you can influence a game by shouting from the sidelines.

"With the fans in the Premier League shouting so much, the players can't understand you. That's why I'm always on the bench. You have trained them to read the game by themselves. It is much more important that they are more involved with the game, that they make their own decisions. It is like a child, you educate.

"Sometimes they can't read that but then you have half-time or you have a (substitution). Then you can say to the player who is coming on to the pitch how they have to play in their position. You have to transfer that."