**Does running with a jumper (i.e. causing yourself to sweat more during a workout) increase the effect of a workout?**

If the answer is no, then what does running in a jumper do? I've read it doesn't help you to loose weight (because you're loosing water rather than fat), and you've got to be careful you don't dehydrate yourself... so does it do anything positive, or should I stick to shorts and t-shirt?

I used to run in shorts and t-shirt, but I've switched to joggers and sweatshirt because it feels harder, and I assumed it was doing more good for me (because I can feel my body working harder running the same distance).

(I guess "effect of a workout" is ambiguous, so to add some context for my case: My intended effects of running are to keep building my stamina, improving my fitness and keep my body toned.)