A good way to get your training minutes right is to set your team's lineup for your three game week something like this:
Play your starters as starters your second string as subs and your third string as third string in the toughest league game of the week. Use let coach decide or strictly follow depth chart
In the easier league game of the week set your second string as starters your starters as subs and scrubs as third string. Use strictly follow or depth chart until 4th.
In the scrimmage do not even suit up any player that has more than 60 minutes.
This is not an exact method and needs some tweaking occasionally, but this is how I start off each week's planning and I do a pretty good job keeping my main guys in pretty good game shape.
Once I scored a basket that still makes me laugh.