The Liverpool striker underwent knee surgery at the end of May, but made a two-goal return to action in his first match in five weeks against England last Thursday.
Suarez told The Mirror: "I was not really 100% fit and sometimes things turns around.
"I was the other day really at the limits of my physical capacity and for the last match for Liverpool, I was full of cramps and I was tired.
"But of course you have a certain experience and you can build yourself up and come to the next assignment and this is what I am doing. I am building myself up again for the game against Italy."
The winner of La Celeste's clash with Cesare Prandelli's side will qualify for the last 16.