Right about now is when people involved in the Olympics are afraid they will last forever.

I know some people not here feel the same way. Those who don’t like their network programming pre-empted for girls on the parallel bars, or are sick of insta-experts at the water cooler talking about Michael Phelps and Shawn Johnson and Osain Bolt.

When you’re actually inside the Olympics, you eventually come to realize that working through the Games almost could be an Olympic sport. It requires preparation, stamina and concentration and speed — at least of a mental sort.

It’s a grind. And it’s that during the weekend in the middle of the Games — this weekend, that is — that pretty much everyone involved “hits the wall” — to use a marathoning term.

How can we tell?

You feel it in yourself. You don’t have the spring to your step you did that first weekend.

You fall asleep inside of 60 seconds when your head hits the pillow. You fall asleep on bus rides. During slow moments in the stadiums. At your work station.

Your best moment is getting into bed. Your worst is getting out of it.

You get crabby. Argumentative. Short. None of us are quite as friendly as we were 10 days ago. That includes the volunteers. Those odd little habits of the foreigners around you have gone from “amusing” to “really annoying.”

You realize you haven’t eaten a fruit or a vegetable in days. And you feel it.

Anyway, I’ve been through this before. And it’s interesting how it’s always this middle weekend that makes you feel like you’re climbing Mt. Everest. You’re a long way up the mountain … but you’ve got a long way to go, too.

(To be exact: Nine days done, if we count Opening Ceremonies; one in progress; seven to go.)

The first blush of enthusiasm for the biggest of sports events (in terms of scale; the World Cup is more popular, yes) is gone. But the end is not yet in sight. The thought of another long day, and another and another and another … it’s just too far out to see the end.

I was prompted to write about this by a sight I took in while walking, an hour or so ago, through a lounge area next to the main work room. Organizers put up eight or nine couches in the shape of semi-circles — for journalists to sit at while having a coffee or a sandwich. But every single couch was occupied by a journalist sprawled out, sound asleep.

Oh, and two more thoughts about this OFS (Olympic Fatigue Syndrome).

1. It has become an even tougher grind in the past 12 or so years — since NBC talked the IOC into staging major events in the morning. Now, with big events at both ends of the day, a 16-hour workday is a reality for writers. Do the swimming or the wrestling or the gymnastics in the morning, write it, kill a few hours, then go see the track and basketball at night, and write that … and after a week of that, you’re trashed.

2. The rise of the web and the insatiable appetite it has for content is killing us. Writers struggle to do more and do it faster. Editors strive to give that enormous volume of material at least a perfunctory glance before it gets onto some official site. (Some of the “inside” people, sports editors and copy editors, have the most brutal schedules of all; a USA Today reporter told me that his editors are working on four hours sleep.)

The Olympics always have been tough. They are getting tougher. And it’s not just a function of being old or worn down from the 12 I did before this one.

If I remember … a week from now I’ll do a post about Post-Olympics Flu. When all these thousands of people will go home sick or get sick soon after arriving home.

It stems from exposure to thousands of other people with damaged immune systems … but mostly it is about abusing your body and your nervous system for some 20 days, and the damage finally coming to the fore the minute you slow down, and the adrenaline goes away.