The Premier League's 38-game schedule is not as onerous as in the second tier, where 46 matches are played, and the Scot is not worried about juggling top-flight commitments with competing in cup competitions.
Cardiff travel to West Ham on Tuesday for a League Cup third-round tie in what will be their second game of three in the space of seven days.
But Mackay believes that his side have the fitness to cope.
"I think it is easier for us to retain that work-rate when we have a number of games as there are slightly fewer games than in the Championship, where we regularly played Tuesday and Saturday," he said.
"You now have more time to recover and we have a lot of good people here in terms of our sport science and medical people who help the players recover.
"They are a very fit bunch, they run hard for each other and that will not change over the course of the season.
"No matter what happens in terms of results the effort will not change, it has not for two years and it will not start now."
