It's about preparation. Approximate gut motility for a healthy adult on a light diet is about 48-60 hours. So, stop eating 3 days before you leave, poop out all you possibly can before your 3 day period starts. Drink about 500ml water per day in the days leading up to the 3 day period. It wouldn't hurt to prep with a mild laxative to remove as much gut content as possible.

Once the timer starts, start eating small amounts only after the first day. For water, about 500ml per day. The good news is that what you pee out can't take much more space than the fresh water you drink.

This assumes you are relatively sedentary. If you perform manual labor during the 3 day period, you'll need to increase water intake, and possibly food intake, to avoid exhaustion.

I was here for... Whatever this is...

My only advice would be to have a back up plan. If you fail to plan, you plan to fail, and there's no guarantee you won't get an unpleasant surprise. You say you'll use the toilet if you're about to shit yourself, but what if you can't make it and do end up shitting yourself because you put it off so long?

Lemmy history!

You said if we guess you'd confirm so here's my attempt.

Are you participating in like one of those TV competitions? Will you be filmed if you poop and that's why you'd rather not?

It’s ok. He/she/them will understand that people do poop. They aren’t worth it if they can’t Accept this

Is the goal to keep the poop inside your body? If it's allowed to come out and play, you could blend it with gatorade and consume it as soon as possible to minimize time spent outdoors.

One of the more interesting posts I've seen here

This has to be a kink thing, one of the weirder ones. Holding a plug, not sweating, because it is not wished?

Else it is something illegal. Drug mule, crossing a border which would either make the drugs visible, or maybe another crime to not leave obvious DNA traces. No sweating to not look suspicious on control? Not much stuff to disguise the longer travel?

Im just posting so I can see my username on one of Whang's videos one day.

It’s been 6 days since the original post. OP was 3 days out from the poopless leg of his trip. OP, I hope everything went according to plan!

Please update when back!

Honestly, I’m just commenting to say I was here.

I really wish I knew what I did in the past to achieve this. Depression and poor eating habits?

Im dying at the urgency. "Guys tell me how to not shit for 3 days AND DONT ASK QUESTIONS DAMNIT"

Get your bowels empty in the days leading up to it. So don’t eat. Anything. 2 days before you can relieve yourself start eating small amounts of protein.

Or, better yet, don’t even try to do this. You’re very unlikely to succeed and therefore your effort is going into preventing an inevitable situation rather than figuring out how to deal with the inevitable problem once it arrives.

I wonder if doing a colon cleanse beforehand help? Similar to what people do before a colonoscopy.

Also, it is an odd request but I’m now fully vested in your post to see what others suggest.

Good luck mailing yourself out of the country.

The important first step is preparation. You need to clean the pipes. There should be nothing left inside you before you commence on the trip. So take some laxatives and do some cleaning. After you’re thoroughly pristine you must only consume a clear liquid diet, so clear juices and soft drinks (make sure you consume the full sugar version because that’s how you’ll get your energy). Take a multivitamin each day. On the second or third day take an Imodium, this is likely overkill but you won’t poop. Return to a normal diet on the third day but do so gradually over the course of a day or two. I cannot guarantee that this method will not damage your health and the risk will likely be greater if you have other health conditions, but you wont poop sooo.

Such an oddly terrifying post.

I'm honestly more curious about this than I was about any of the locked safes.

If it's important you can easily just not eat for three days. Otherwise, there's nothing you can eat that will be safe and prevent you from pooping.