Every inmate has his own program - the way he chooses to do his time. In a highly structured car like that of the Sureños, this is built around the car's mandated program. But he still has his own program. He might choose to study, he might choose to work on his case and spend a lot of time reading legal materials, he might choose to work out more than most others, he might choose to spend his time hustling and building up a nest egg, he might be working six hours a day/five days per week, or he might just choose to spend his time on the yard and talk shit with his homies. This is something you should seriously consider thinking about when trying to figure out how you're going to approach your roleplay. Not everybody does the same time, even in the regimented Sureño car. As long as a guy is following the (hard) reglas, attending the mandatory workouts and paying his dues, the car isn't really concerned with how he chooses to do his time.
Exercise is a serious part of almost every inmate's program. To quote an ex-felon, "everyone in there is in beast mode". You should consider the importance of health to your character. If he takes his exercise seriously, he's probably working out in his own time and not simply attending the group workouts. He probably structures his commissary regimen around nutrition and supporting his muscle gains. He probably has planned rest days. A real life exercise program can be easily adapted to the prison environment. Real inmates do it, and you can too.
You should also consider structuring your character's program around his sentence. It's a good idea to keep in mind how long you're roleplaying your character's sentence is, how you're progressing through the sentence on a development level (obviously you can't do eight real life years, everyone skips forward), and how long he has left. Your character shouldn't be in the same frame of mind as you are about prison. You're in SACF by choice, roleplaying an inmate. Your character isn't. He's been incarcerated and he probably has a date to work towards. If he's doing life, there are ways to roleplay around that too. Don't make it seem like your character is complacent behind bars.
