Most of us know that protein is the nutrient in red meat that benefits anyone who is training, but there’s a lot more to it. According to Rick Hall, a registered dietitian and nutrition lecturer at Arizona State University, “Beef boasts nine essential amino acids and has a high biological value, which means it’s very digestible and usable by the body.” That’s the reason many bodybuilders eat beef during their “bulking” phase. In fact, studies show that foods with a high biological value are what you should eat to repair your muscles postworkout. As for vitamins and minerals, the beneficial minerals in beef include the antioxidant selenium, highly absorbable iron and immune-boosting zinc, while the vitamins are thiamin, riboflavin, niacin, pantothenic acid, B6 and B12. Plus, it’s loaded with creatine. Round cuts are the leanest choice, with the best protein-to-fat ratio, and according to the USDA, a serving of broiled beef is about 28 percent protein. If you can get it, grass-fed beef is best.