I've heard subbing by fatigue is more efficient than doing it by minutes... if I want my starting C to play around 30 minutes per game, and my back up to play around 10 per game, would I put my back-up at 'fairly fresh' ? What's the most effiecient way to do this? Thanks

Both of your teams have starting centers with 70 stamina.  Even on slowdown I'm not at all convinced you want them playing 30 minutes.

Depends on your starters stamina.  If 85 or higher you can probably set him to getting tired. If below that you may not be able to get 30 minutes out of him.  I currently have a guard with 100 STA set to getting tired and he is right at 30 MPG playing a normal tempo most games.  Even if you set the guy to very tired there is a good chance you get 27 minutes out of him.

thanks. Didn't realize how important stamina was here

so since they have such low stamina, is it wise to set their fatigue to "Getting tired" ? I have played one game so far and had his set at "very tired' and he played 33 minutes. Too much for a guy with 52 stamina?

Yeah, too much.  You kind of have to get rid of real-life ideas of stamina.  It's not super far off, but you're not going to find anyone super productive playing 35 minutes or so like you do in real life.

Thanks isack. So looking at my team what's the best way to set their fatigue? Should I just keep my starters at "Getting Tired" is that the best way to get subs in and keep my starters fresh for the majority of the game? Is that the most common way, just leaving guys at "Getting Tired" ?

No problem.  Ideally, I think you'd like to have enough depth to set everyone at fairly fresh with some limited exceptions.  When you have walkons or bad depth, you have to sacrifice and go "getting tired."  I wouldn't ever advise going lower than that. 

I've only ever once not used "fairly fresh," and that was at a position with a dominant starter and a way-below-average backup.  Only with a huge dropoff would I not set everybody to fairly fresh.

I go to getting tired a lot, but usually not below that.  It depends on the team and how good the player is. 

This is what exhibitions and non-con play is for - it takes some experimenting to find the right setting.  I usually watch a player's FG% and fouls on the assumption that if he's getting too exhausted, his stats will fall.  If I have doubts, I'll skim the play-by-play log and watch whether he really falls off late in the game.

If I have a couple of good players and my backups suck, there's no way I'm setting my starters to "fairly fresh".  If they don't get 20-25 minutes minimum, I don't even have my usual forlorn hope of winning.