This is more fitness related than Paleo, but it’s something I see people doing from time to time that highlights how little most people understand about how weight loss works. Let me break something down in very simple terms: sweating a lot has nothing to do with how much weight you lose.
Sure, if you go out for a long run, and you sweat a lot, that sweat had mass, and as such, weighs something. All that sweat that was in your body and is now outside of your body accumulates, and the result is a loss of weight. But guess what happens when you take a sip of that water bottle? It all comes back! That’s because sweat doesn’t come from fat. People think they’re, “Burning fat” when they sweat, but actually, they’re just burning calories. Those calories mostly come from the food they’ve eaten prior to exercising. This energy was stored in the blood for short-term use. If they expend the energy in the blood, then the body starts extracting it from fat cells, but it’s still not burning fat, per se. It’s using energy stored in the cells where the fat is, and it basically deflates them like balloons: the cells themselves are still there. It takes between 45-90 days for those cells to die and get flushed from your body if the fat cell isn’t filled back up with more energy. This is key to losing weight and why cheating does more harm than good, and can either drastically slow or even negate any progress made toward weight loss.
Exercise is good, but ultimately, it’s changing your diet that allows you to lose weight. Keeping those fat cells empty and from reinflating is what works long-term. I will admit; this is an oversimplification of how fat cells work, but in my experience, this analogy works because it matches what I’ve seen happen in my own body and those of others. I encourage you to read up and find more about what is really going on, and why cheat days and fat suits don’t actually help you lose weight. Oh, and there’s no such thing as burning fat, either. Sorry.