I'm just starting to gain some weight... how do I maintain it during basketball season?!?!?!?!??!?

I'm 17 years old, 6'4'' 168-170 pounds, and have a metabolism that burns like 134082340972843098723 calories per minute (slightly exaggerated), and I've finally found a workout that is slowly helping me get a really nice tone to my body... there's one problem though... basketball season is coming up which means that my workout routine will be slightly less regular because I will be so busy with basketball, AND during the first few weeks up TOUGH practice (conditioning and gettin back in bball shape) I'm afraid i'll lose all that weight that I spent ALL SUMMER GAINING! what can i do to ensure that that muscle does not deteriorate AT ALL DURING THE 4 MONTHS of extreme cardio workouts???