If your players (especially the starters) have decent stamina, I don't see any problem with it. For me, I want most of my players (especially the starters) to have at least mediocre. I usually train stamina during the all star weekend and one week of the playoff, when there are only 2 games per week. I think good stamina really helps in the 4th quarter.
But players' stamina drops as time passes by, so I think spending 1 week training stamina is not a bad idea.