Macari says Adam is reaping the rewards of his extra fitness training.
He wrote in The Sentinel: "There's no secret to it. Talent and a good footballing brain is all well and good, but unless you've got the body and the willingness to get around a football pitch, it's all pretty useless.
"Adam is simply reaping the rewards for hard work Monday to Friday and there must be a lesson there for any footballer at whatever level of the game.
"There's no tougher job physically than playing in a midfield two and being expected to get up and down that pitch.
"But Adam did that pretty well as far as I could see against Manchester United on Saturday and certainly gives the manager far more options as a result."