This...you hit the nail on the head as to why I'm trying to go minimalist/ legit.
I'll be in OTS, and they even restrict caffeine for a few weeks I've heard. It's why I'm giving up pre's as well. I have heard of people using aminos in their camel packs though.
Going to Lackland AFB? At 37, wow, good luck! Went through when I was 19, am now 38. The last drug tests I took were in early 2003, as I enlisted 1999 we're focused on narcotics. No one was looking for PEDs then. Probably still don't test for them?
Funny story, After basic in 1999, where I got honor grad, and a DI called me out to drill-march for new OTS candidates my graduation day in basic... I then transferred to long tech school for sat-comm at Ft. Gordon near Augusta. My roommate, Crazen, got hauled off in an orange jumpsuit 6 of 9 months into long two part tech school.
All because he hid alcohol in his wall locker when they ran drug dogs through at 3am randomly. Twice he was caught this way. Everyone knew rules of, off-base, off-duty, of age - to drink. Be back in formation or in barrack curfew on time too. My former tech school roomie wrote a letter back about to our sat-comm class about how hard military prison is on him because he could not keep the alcohol out of barracks.
Ironically, I was going off base lifting regularly for my first time at Power House gym in Augusta, after duty days were done. The Big, bad, black owner of the gym ripped me off couple hundred bucks for unknown steroids he never delivered in '99 - after selling me on them. I was hella naieve and glad I waited til now, research and studied, and chose my own correct Anabolic and joint support means. As I made good Natty gains still being natural at 19 then, so steroids was a poor idea anyway to try blindly from that gym owner, me without a clue at 19...would have probably screwed my endocrine system (with no modern cycle support or PCT protocol then).
Also, Ft. Gordon had a GNC on base and they actually carried early Andro PH then, before all the DASCA bans... so it was not uncommon for guys to have protein, aminos, supplements in tech school- after basic or OTS.
Stay clean in boot, they will give you 600mg strong ibuprofen if you get shinplints running, etc. In OTS, (by the way OTS seemed like mini boot to me) officers then had more academic and less drill work, and only 6 weeks OTS weeks versus 9 weeks long for enlisted. At age 37 this may help, lol.
After OTS, stick advice for SARMs and Mk-677 given above, they are not being tested for unless you are an Olympian. If you move off base eventually, you can increase your PED choices. In tech school, there's still morning PT, work, then lifting after duty day is done. It's tough, but military chowhalls and shakes got the job done.
Last funny bit, I walked into JAG lawyer office at Ft. Gordon, right before leaving tech school, asking to see if they could help my friend (me) to get this gym owner for ripping me off. JAG was kind, i did not admit it was me, and did not return to JAG. I realized to get the gym owner I would have had to admit attempt to buy roids - also might put me in an orange jumpsuit.
