W/ sim sliders, the fatigue is set on 57 and stamina at 50. Reason I went w/ a higher stamina was because I felt that the bigs didn't get the proper ratings for stamina and were getting way too tired early on (cause their ratings were too low imo), like being at 3 bars 2-3 minutes into the game.
So by bumping up stamina to 56, I am basically giving all players a 9 point boost to their stamina ratings. So now bigs have a higher stamina rating to start with and aren't tired 2-3 minutes into the game. I have still noticed that they still get tired pretty quickly, more like around 5 minute mark instead of the 3 minute mark. But if you need them to get tired faster, just bump fatigue up a bit.