With only 90 calories in a three-ounce serving, shrimp is an ideal protein for runners watching their waistlines. Plus, it's a good source of vitamin D. "Vitamin D helps the body absorb bone-building calcium from foods," says Rebecca Scritchfield, R.D., a Washington, D.C.—based sports dietitian. Jerk seasoning, sweet potatoes (a leading source of vision-protecting vitamin A), and black beans give this stir-fry Caribbean flair.