Protein Needs of Athletes: What Does the Research Say?

By Nancy Clark, MS, RD, CSSD

Protein is a popular topic among both recreational and competitive athletes, many of whom are confused about how much protein they need, when they should eat it, and the best kinds of protein to choose. The following information will answer some of the questions that athletes often ask about the role of protein in a sports diet. The information is based on data presented by prominent protein researchers during the 2012 Annual Convention of the American College of Sports Medicine.

Do some athletes need more protein than others? Just as children have high protein needs during growth periods (0.6 gm/lb; 1.3 gm/kg), athletes also have higher protein needs. Recommended protein requirements for various types of athletes are presented in the following table (Table 1). These recommendations assume the athlete is consuming adequate energy from his/her intake of carbohydrates and fat. Athletes who restrict food intake end up using some protein for fuel, thus they need a higher protein intake. Most athletes consume approximately 0.7 gm/lb; 1.6 gm/kg/day, so they easily meet the protein recommendations without supplements.

Table 1. Protein requirements for various types of athletes

The best way to stimulate muscular growth is to lift weights or do other forms of resistance exercise. To support muscular development after hard lifting, all athletes need to consume high quality protein (with all the essential amino acids) in close proximity to their training. High quality proteins include milk products, poultry, eggs, fish, lean beef, all meats, and soy protein.

How should I spread my protein intake over the day? Is it better to have a large steak for dinner or smaller protein doses every few hours? Many athletes eat very little protein for breakfast, but then feast on a high protein dinner. Current research suggests that the trick to optimizing muscular development is to spread protein intake evenly throughout the day. For example, if you were having a carbohydrate-based breakfast (such as oatmeal or a bagel) and a salad for lunch, you would be wise to include more protein in those meals.

The goal is to consume at least 20 grams of protein every 3 to 4 hours. For example, a 200 lb (91kg) athlete who chooses at least 20 grams of protein per meal and snack will easily consume the recommended 150+ grams of high quality protein: 3 eggs for breakfast (21 gm protein); 2 cheese sticks for a morning snack (14 gm pro); 4 oz. deli meat in a lunchtime sandwich (28 gm pro); an afternoon snack with 6 oz. Greek yogurt (18 gm pro) mixed with 1/2 cup high protein cereal (6 gm pro); a medium (6 oz). chicken breast for dinner (42 gm pro); and 8 oz. cottage cheese (24 gm pro) before bed easily does the job, with no need for protein supplements.

Are all dietary protein sources the same? What about supplements: whey vs. soy vs. casein? Different types of proteins are comprised of differing amounts of essential amino acids (EAA) and have different rates of digestion. For example, whey is more rapidly absorbed than casein. Soy protein contains fewer EAA’s than whey or casein. The EAA leucine is a key “trigger” for building muscle, so leucine-rich foods with rapid digestive properties are best for recovery from resistance exercise. Animal proteins, including plain or chocolate milk, lean beef, and tuna, are leucine-rich. Plant proteins contain leucine, but in lower amounts.

Because casein is slowly absorbed, consuming casein-rich foods before bedtime (such as cottage cheese) can help support muscle-building processes throughout the night. This may be particularly important for athletes seeking to maximize muscular growth during building seasons, such as during a pre-season training program.

Do other nutrients consumed at the same time as protein affect muscle recovery? Yes. You want to enjoy carbohydrates in combination with protein. Carbs are important to refuel muscles, while protein’s job is to build and repair muscles. Adding some fat, such as low-fat or whole chocolate milk vs. fat-free chocolate milk also seems to increase protein uptake. Researchers are unsure why fat enhances protein uptake, so stay tuned!

Does adding protein to a sports drink enhance performance and/or recovery? Studies suggest no improvement in either endurance or speed (time trial performance). The benefits of having protein in a sports drink relate more to recovery. Protein contributes to slightly higher muscle protein synthesis and glycogen replenishment.

Should I eat protein before exercise to promote post-exercise recovery? It won’t hurt, but it may not help. Eating 20 grams of protein 45 minutes before exercise increases amino acid uptake by the muscles as much as eating protein immediately after exercise. Take note: 20 grams of protein per recovery-dose is plenty. Athletes who consume higher amounts of protein either burn it for fuel or store it as fat.

When athletes lose weight, they also lose muscle. Is there a way to prevent that loss? About 25 to 30% of weight loss relates to muscle loss. To abate this loss of lean tissue, dieters can 1) create just a small calorie deficit (as opposed to starving themselves with a crash diet), 2) choose protein-rich meals and snacks, and 3) include resistance exercise twice weekly in their training.

How should vegetarians, particularly vegans, meet their protein needs? Vegan athletes can successfully meet their protein needs by eating a variety of plant foods. Most grains contain all 9 essential amino acids, just in lower amounts than an equivalent serving of animal foods. Hence, vegans need to consume generous portions of plant protein (grains, beans, legumes, nuts, soy) to compensate for both the lower density of the protein as well as the fact that plant proteins are less bioavailable due to their fiber content.

The smartest way for a vegetarian to optimize protein intake is to consume an adequate amount of food. If a vegan is undereating, an energy deficit can easily lead to muscle loss. Vegans who want to lose fat, not muscle, will want to focus their limited food intake on protein-rich plant foods. More tofu anyone?

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Nancy Clark, MS, RD, CSSD, is a sports nutrition consultant with the Boston Red Sox and author of Nancy Clark’s Sports Nutrition Guidebook. For more sports nutrition information go towww.nancyclarkrd.com.