Playing for 3 hours non-stop is a little excessive and can cause excessive sweating caused by
ketosis if you have a fast metabolism like me (not eating enough
carbs) and that isn't a good thing. If you are healthy, there really shouldn't be a terrible smell to your sweat. The smells are toxins being released, which is good, but if you sweat regularily, keep well hydrated and eat properly, you shouldn't smell bad when you sweat at all.