The Bundesliga holders' sporting director is refusing to accept excuses for the squad's fitness and wants the whole team ready to play twice a week if necessary
Pep Guardiola's men defeated Borussia Monchengladbach 3-1 on the opening day of the season before securing a 1-0 win at Eintracht Frankfurt on Saturday.
However, the former Germany international is adamant that his side must get into better shape following two unconvincing performances in as many Bundesliga games.
"We need to see as soon as possible that we have reached a high work-rate, to be able to play two or three games in a week," he told Bild.
"Only one or two players have done that so far. The players need to do more to get into the absolute top condition.
"[Against Frankfurt] it was hard, it was warm and the grass was like two feet tall but all these cannot be excuses."
Bayern will continue their defence of the Bundesliga title against Nurnberg on Saturday, with kick-off at 15.30BST.