Sunderland boss Roy Keane admits he may tone down his training after Saturday's 1-1 draw with Fulham.
Keane, who has been hampered by injuries from the off this season, said: "We are asking players to keep pushing their bodies.
"As a manager, I have got to ask myself why we were so flat in the first half.
"Possibly we are training too hard, possibly we are pushing the players, and sometimes you can leave it out on the training pitch.
"Credit to our players, they train extremely hard. There is always that intensity, there are always tackles flying about.
"But then I ask myself why have we got a load of injuries?
"That is down to me as a manager and we have to look at that because in any game in the Premier League, if you start slow, it's not like a light switch, you cannot just switch it on.
"You have got to start quickly, and it was a long 45 minutes for us. But I am grateful that we got to half-time."