hey /fit/i am a college student (commuting so i dont worry about fast food shit) and i went to the gym over the summerid like to retain the muscle i gained over the summer, so i am doing lunges, pushups, i do cruches/leglifts, and do pullups and chinups on trees outside. i also run for about 30 minutes a day to the grocery and back to school for lunch.anything else i can do to retain/gain muscle without actually going to a gym?i would like to try parkour, it looks like fun, anyone know a place in NJ i can go to learn about it in a group so i dont look like a crazy person?