Sorry about sounding like a dinosaur, but this thread brings back memories from my army medic experience of nearly 50 years ago.
I did a 5 week assignment, at a Missouri Army training base, assigned to a special remedial physical fitness company, for non standard draftees. In order to enhance conscription numbers, Selective Service waived height, weight and fitness standards for Army draftees. Overweight conscripts were sent to a similar program at a Louisiana Army base, and we received the classical 90 lb. weaklings in Missouri. Many of these kids were physically too weak to carry their duffle bags from uniform issue to their barracks without help, so the Army cycled them through a 30 day intense physical training program, prior to assignment to a basic training company. The Army lingo for the program was Operation Runts into Grunts, since most of them would end up assigned to Infantry.
Without boring you with details, the recruits did PT, all day, 6 days a week with usually one weekly all night sand bag weighted ruck march. They were pushed to their limits, and required Medics to monitor their condition, and scrape them up off of the grinder when they collapsed from heat or exhaustion. In the period I was there, they wore PT Alpha ( gym shoes, tee shirts, jocks and shorts), but shortly thereafter these companies converted to BDU's and Boots, just like all other trainees.
For what it is worth, the Army issued them small size BUB jockstraps. These were serious jocks, stayed in place and tightly held the man parts all day.
About 17:00 hours each day, when dismissed the recruits gladly returned to the barracks, threw their sweaty PT gear in the laundry bin, and looked forward to their showers. My partner and I were also glad to get out of our BDU's and join them in the shower, as we typically had a good workout walking or stretchering the trainees to the recovery tent when they went down. Additionally, we had to weigh each recruit, and record vital signs 30 minutes after they stopped PT so needed to be near the shower room.
Well, hard-ons happened. Certainly nothing relating to sexual horseplay, but it seemed like every few days a recruit would display a serious erection in the shower, and like clockwork it would have a contagious affect, others would follow. I'd never seen anything like it but it made for a crazy sight to see a half dozen poles, ranging from 3" to probably 10" pointing straight out or even skywards. My guess is that these hard-ons may have been caused by nothing else than their dicks deciding to stretch out a bit, having been constrained by tight jockstraps all day.
Once, the PTI (physical training instructor) walked by the shower and went ballistic about the erections. He told them men that if they had enough energy to exercise their dick muscles, they certainly had enough energy for more PT. He gave them two minutes to get out of the shower, grab PT clothes out of the laundry bin, ANY ONES CLOTHES, and be formed up in front of the barracks for a run back to the drill field for more PT. I don't recall specifically, but I doubt that any of them sprouted hard-ons when they showered down after the bonus PT session. This only occurred once during my 5 week assignment, but still was memorable.
