CUMMING — Luckily for Austin Collins, he works at Riverside Military Academy in Gainesville. The 29-year-old, who is employed in the private school’s information technology department, said he took advantage of some military-style fitness training through his employer in preparation for his leading role in the Cumming Playhouse’s current production of “Tarzan.” “This is a very physically-demanding show, so to help me get ready for it … I had some of our sergeant majors at the academy get me in the gym and train me because, being a computer guy, I’m not physically fit,” Collins said.