I recommend eating a lot of cheese and absolutely NO fiber. Not sure if it will make you sweat less, but I'm pretty sure if I ate only cheese for 3 days, it wouldn't be too hard to wait till the end of it to poop. In fact, I may need some help at that point... maybe you should eat some fiber like a couple hours before you do plan on trying to poop, and also drink lots of water at that point, too. I personally find cheese very "helpful" in getting myself constipated, and fiber + water to be a great way to smoothen the pooping process.