Depends on what the fabric is. I'm assuming these are workout shorts or athletic shorts of some kind. Dawn Plus Odor Eraser is dish detergent designed to remove odors from plastic (tupperware etc.) and I've had good luck with it on nylon blends, Gortex, some other synthetics - just soak the shorts in a lot of it for a couple of hours. If the shorts are mostly natural fiber (cotton blend or similar), then use tide with febreeze and add some oxyclean to the wash. If they are one of the nylon-based blends (especially the moisture-wicking ones) then you're probably S.O.L.. Even if the odor seems to be gone after you wash them, as soon as they get warm you'll smell it again. If the label mentions nylon, dri-fit or vapor-wick, I'd chuck them. Good luck.