Cuellar thinks it is a positive as Sunderland look to make a flying start to the new campaign.
He said: "The way we'll approach this pre-season, I think it will make us a lot stronger physically.
"In the last few games of last season you could see the players pick up little injuries or cramp because we were working so hard to win every match.
"Sometimes, you give more than 100 per cent and we didn't have that extra fitness we needed. I don't think we're going to have that problem next year."