I'm not writing this from firsthand experience of the real thing; it's been a long time since I've been in any kind of fight. I was just thinking back on some of the descriptions of fights in Afghanistan and Iraq, particularly from a writer like Yon. Just reading about this gets your system pumped up. One thing I do know is that while hard, realistic training will stress you out, nothing equals the wear and tear of a real fight. I've never been in a real life-or-death struggle(happily); and the closest I came to true combat exhaustion was from a demonstration, of all things.
I've mentioned I used to play around in the SCA. Well, one evening the local group had been asked to do a demo for some organization. The guy I was to fight was working hard at a Japanese persona, and at that time fought only with katana. We'd sparred some times before, and that night we agreed to use his chosen weapons. Time came and we got up on the stage and stood facing while we were introduced, rules explained, etc.
I had always seen SCA combat as a game. I'd never taken it seriously, seeing it as a real fight. Until tonight. For some reason, this time, I looked at Taisho and thought, "You're mine". Everything around me faded into the background; I could hear everything but only the sounds from my opponent counted, I knew where everything/everyone around me was without having to glance aside. And the fight began.
And this time it was a real fight to me. I was fairly skilled, but not taking it dead-serious kept me from getting much better. But this time, everything was focused. He was better, better than me at this style but I had him on the defensive from the start. I have no idea how long it lasted, probably no more than a minute, then I feinted him out of position and made a beautiful cross-body cut into him, and he folded and went down. I stepped back, they called me the winner, and then, I couldn't move. I mean I couldn't move; I had to lean my helmet on the sword pommel- point on the floor- to keep from falling over. Truly realistic training is much like a real battle, it drains you, and this was the first time ever in SCA combat I'd done this. I think somebody led me off the stage, at least I didn't really remember walking off. And after we both calmed down, Taisho basically said "What the hell was THAT?" I said something like "I remembered to concentrate this time" and left it at that.
I was wearing a steel helmet that probably weighed about 6-8 pounds, a padded tunic and leather and steel scale laced onto a leather backing body armor, shoulders to mid-thigh, some leather armor over arms and gauntlets for the hands. Probably about 45-50 pounds total weight, and the sword weighed about three.
What made me remember this was thinking of what our troops wear. Fatigues, and armor, often elbow and knee pads, helmet, goggles, sometimes night-vision gear. Ammo and first-aid kit and water and food and personal weapons. Sometimes a belt for the guy with the machinegun or other ammo for somebody with the heavy-weapons stuff. And so on. David Drake wrote in Fortress that what a lot of people didn't realize is that the infantry grunt carries everything he needs on his body, and hopes it's enough at the same time he's sweating to carry it all. And in real combat; real outdo the other guys, kill or die combat. I don't think I can imagine the level of stress, and the let-down at the end, when the shooting stops. And then they have to stay mobile and alert until things are secured and they're relieved...
A lot of people have said it better than I can; we OWE these people bigtime for doing what so many of us cannot for whatever reason.