How they build muscle: The protein in eggs has the highest biological value—a measure of how well it supports your body's protein needs—of any food, including beef.
But you have to eat the yolk. In addition to protein, it also contains vitamin B12, which is necessary for fat breakdown and muscle contraction. (And no, eating a few eggs a day won't increase your risk of heart disease.)
How they keep you healthy: Eggs are vitamins and minerals over easy; they're packed with riboflavin, folate, vitamins B6, B12, D, and E, and iron, phosphorus, and zinc.
How they build muscle: Almonds are one of the best sources of the kind of vitamin E that's best absorbed by your body. The vitamin E in almonds is a potent antioxidant that prevents free radical damage after workouts. If you don't know what free radicals are, Google it. It's a lengthy topic that's too vast for our purposes here, but to sum it up, they're nasty and they're everywhere and they mess you up. Antioxidants combat them for you. The benefits of almonds will help you build muscle faster and recover more quickly. Have two handfuls a day.
How they keep you healthy: Almonds double as brain insurance. A recent study published in the Journal of the American Medical Association found that those men who consumed the most vitamin E—from food sources, not supplements—had a 67 percent lower risk of Alzheimer's disease than those eating the least vitamin E.
How it builds muscle: It's got high-quality protein and omega-3 fatty acids. "Omega-3's can decrease muscle-protein breakdown after your workout, improving recovery," says Tom Incledon, R.D., a nutritionist with Human Performance Specialists. This is important, because to build muscle you need to store new protein faster than your body breaks down the old stuff.
How it keeps you healthy: It reduces your risk of heart disease and diabetes. Researchers at Louisiana State University found that when overweight people added 1.8 grams of DHA—an omega-3 fatty acid in fish oil—to their daily diets, their insulin resistance decreased by 70 percent in 12 weeks.
How it builds muscle: "Yogurt is an ideal combination of protein and carbohydrates for exercise recovery and muscle growth," says Doug Kalman, R.D., director of nutrition at Miami Research Associates.
Buy regular—not sugar-free—with fruit buried at the bottom. The extra carbohydrates from the fruit will boost your blood levels of insulin, one of the keys to reducing postexercise protein breakdown.
How it keeps you healthy: Three letters: CLA. "Yogurt is one of the few foods that contain conjugated linoleic acid, a special type of fat shown in some studies to reduce body fat," says Volek.
How it builds muscle: More than just a piece of charbroiled protein, "beef is also a major source of iron and zinc, two crucial muscle building nutrients," says Incledon. Plus, it's the number-one food source of creatine—your body's energy supply for pumping iron—2 grams for every 16 ounces.
For maximum muscle with minimum calories, look for "rounds" or "loins"—meat cuts that are extra-lean. Or check out the new "flat iron" cut. It's very lean and the second most tender cut of beef overall.
How it keeps you healthy: Beef is a storehouse for selenium. Stanford University researchers found that men with low blood levels of the mineral are as much as five times more likely to develop prostate cancer than those with normal levels.
6. Olive Oil
How it builds muscle: "The monounsaturated fat in olive oil appears to act as an anticatabolicnutrient," says Kalman. In other words, it prevents muscle breakdown by lowering levels of a sinister cellular protein called tumor necrosis factor-a, which is linked with muscle wasting and weakness (kind of like watching The View).
And while all olive oil is high in monos, try to use the extra-virgin variety whenever possible; it has a higher level of free-radical-fighting vitamin E than the less chaste stuff.
How it keeps you healthy: How doesn't it? Olive oil and monounsaturated fats have been associated with everything from lower rates of heart disease and colon cancer to a reduced risk of diabetes and osteoporosis.
How it builds muscle: Whether it's in your shins or your shoulders, muscle is approximately 80 percent water. "Even a change of as little as 1 percent in body water can impair exercise performance and adversely affect recovery," says Volek. The more parched you are, the slower your body uses protein to build muscle.
Not sure how dry you are? "Weigh yourself before and after each exercise session. Then drink 24 ounces of water for every pound lost," says Larry Kenney, Ph.D., a physiology researcher at Pennsylvania State University.
How it keeps you healthy: Researchers at Loma Linda University found that men who drank five or more 8-ounce glasses of water a day were 54 percent less likely to suffer a fatal heart attack than those who drank two or fewer.