Konami's new way of handling player fatigue is both realistic and annoying when it happens to your own team around the 65-minute mark. That's only natural, but it'll happen a hell of a lot earlier if you're spamming that sprint button and running full pelt towards every loose ball.
There's no need to do that.
Be more considerate of the clock when sprinting. Obviously, when your wingers are flying down the flanks or your star striker is through on goal, it's a good time to hold down that button. Play enough of the new game though and it becomes clear just how counter-productive sprinting is when chasing to win the ball back.
Going too heavy on the sprint button makes it simple for rival teams to pass around your players. Generally, players are more skittish and less accurate when they're sprinting in PES, so keep that in mind. Standing firm and letting those with the ball come to you, before sticking a foot in, is the best idea.