The Swans have lost two and drawn one since the American took charge, but he has to be given time as he looks to introduce new ideas on the squad he has inherited.
Changes to training is one of them, which suggests the players may not have been fit enough under the leadership of former boss Francesco Guidolin.
"I think (the fitness) has improved but again, there are all sorts of ways to train teams," he said. "Certainly we've tried since I've arrived to have sessions that are a little more intense.
"In terms of physically, it's football reactions, football explosiveness, duels, and it's also true when you have the ball - do you provide enough options on the ball, do you move quickly or is he stranded because everyone is resting? I think there are a lot of little things that need work."