On-the Go Protein
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Protein powder is science's gift to overscheduled people. One scoop has 20 to 25 grams – the equivalent of a half breast of chicken. Simply blend with water or milk, or make smoothies by blending with fruit, juice, ice, or vegetables. Just avoid protein powders with artificial sweeteners, flavors, and colors.

Whey is separated from milk for a high-quality, fast-burning protein that gets to muscles quickly. Look for a pure powder like Optimum Nutrition Gold Standard Natural 100 Percent Whey ($40 for 80 servings ) or Trader Joe's Whey Protein ($11 for 15 servings ), which contain nothing except whey protein. Pair with 25 grams of carbs, like a banana or a handful of whole-wheat pretzels, for recovery after weight training.

Casein is a slow-burning protein, so it takes longer to get to muscles, but it's ideal to prevent tissue breakdown. Whey is better post-exercise, but casein can be used to increase overall protein intake or before bed to help repair muscle. We like Optimum Nutrition Gold Standard Natural 100 Percent Casein ($29 for 24 servings ), which provides amino acids over a longer time period than whey. Casein and whey are combined in some products for a fast, slow-burning mix, like Dymatize Elite Gourmet Whey and Casein Blend ($35 for 27 servings ). Blend with water; drink half after weight training and the other half before bed.

Soy, a fast-burning protein, isn't as effective for muscle building as whey or casein but is an alternative for vegans or people with lactose problems. GNC Natural Brand Soy Protein ($10 for 30 servings ) contains soy protein isolate from non–genetically modified beans.