Trust me if you some kind of trained 8 miles not so bad if you not required to perform on time results. On future soldiers training they run 2 miles and usually check time. Then you enlisting thats not so bad but at end of basic training you should pass APTF. I tryed one. Im really old for military (over 32) аnd for me reqirements was minimal: 2 miles for 15 min. 36 push-ups. 42 sit-ups. I faled that test. The same like everybody. Cuz for age 19 requirements twice more than for me. Only couple of guys who have been selected for special forces passed. I even meet one guy who originally applied for navy but was interrupted for poor results on push-ups on basic training so he tried Army now. And trust me that guy was 6'5" high and his shape was so exellent that he looked like bodybuilder and run 5 and 10 miles marathons regularly. The same time i saw how some real sergants treated weak guys. Made them exercise more and more untill they totally exhosted as punishment for their bad results and shout at them. And make everybody do extra exercise because that guy set up the rest of the group.