Your workout awaits you, and you intend to slay it in full-out beast mode. But as you lace up your shoes, your tummy rumbles. You know you need to eat something to ensure you're adequately fueled to show that gym who's boss, but what? This is not a frivolous question. Eating the right foods before a run or other workout may be the difference between an energetic sweat session ... and being doubled over with stomach cramps.