The Importance of Protein for Endurance Athletes

Edition 7, 2005
By Steve Beaver Born

When I first became intrigued by the possible benefits that supplements and fuels might have on my performance and health, I thought I'd check out the local health food store to see what was available. Pretty much what I remember after walking up and down the aisles of the store was that most of what lined the shelves were these industrial size containers of protein powders. A good majority of the products I saw had labels that were largely taken up by photos of these monstrously huge bodybuilders. A long time passed before I realized that protein isn't just for bodybuilders. In fact, hard training endurance athletes need a substantial amount of protein in their daily diets. If you're one of the athletes who still thinks protein is just for the muscle heads, this article will hopefully convince you otherwise.

As endurance athletes, we go to great lengths to acquire the best possible equipment. We make sure that this equipment is always dialed in and working properly. We take great care to utilize the best possible training program. And if we're smart, we also take care of the third piece of the performance puzzle, nutrition and supplementation.

Endurance Athletes Need More Than Just Carbohydrates

Endurance athletes tend to focus on carb intake and pay little attention to protein. As a result, protein deficiency appears often among endurance athletes, with its attendant negative effects on performance and health. Serious endurance athletes do need considerable amounts of protein, far above the normal adult RDA, because maintenance, repair, and growth of lean muscle mass all depend on it, as well as optimum immune system function. Low dietary protein lengthens recovery time, causes muscle weakness, and suppresses the immune system. Chronic protein deficiency will cancel the beneficial effects of your workouts; instead, you will become susceptible to fatigue, lethargy, anemia, and possibly even more severe disorders. Athletes with over-training syndrome usually have protein deficiency.

This article will focus on how to obtain adequate amounts of the proper protein at the right time in regards to the specific needs of endurance athletes.

Questions, Concerns, & Answers

In addition to the usual education we offer for all our fuels and supplements, the issue of protein intake also requires dealing with some misperceptions. Endurance athletes have certain oft-spoken beliefs about protein intake, and in this section we'll look at the three most commonly voiced.

The first is something to the effect of, "I thought only bodybuilders needed high protein diets." But when you get down to it, we are body builders in some respects, building our bodies to do what we want them to. The truth is that endurance athletes and bodybuilders have similar protein requirements, but the way in which the body uses the protein differs. Bodybuilders need protein to increase muscle tissue; endurance athletes need protein to repair existing muscle tissue that is undergoing constant breakdown from day-to-day training.

Another concern often heard is that "eating a high protein diet will cause unwanted weight gain and muscle growth." Actually, the type of training you engage in determines whether you bulk up or not. High volume endurance training does not produce muscle bulk, regardless of protein intake, whereas relatively low volumes of strength training will. Either way, the muscle tissue requires protein.

"But I thought carbohydrates were the most important fuel for exercise," is the third most commonly expressed belief. While carbohydrates are indeed the body's preferred source of fuel, protein plays an important part in the energy and muscle preservation needs of endurance athletes. Under normal conditions, protein serves a vital role in the repair, maintenance, and growth of body tissues. However, after about 90 minutes of exercise in well-trained athletes, when muscle glycogen stores become nearly depleted, the body will synthesize glucose from the fatty and amino acids of lean muscle tissue. It's a process called gluconeogenesis, which is the body literally cannibalizing itself to provide an alternative fuel option during a state of glycogen depletion. The degree of soreness and stiffness after a long, intense workout is a good indicator of just how much muscle cannibalization you have incurred.


Research has shown [Lemon, PWR "Protein and Exercise Update" 1987, Medicine and Science in Sports and Exercise. 1987;19 (Suppl): S 179-S 190.] that exercise burns 10-15% of the total amount of calories from protein by extracting particular amino acids from muscle tissues. If the endurance athlete does not provide this protein as part of the fuel mixture, more lean muscle tissue will be sacrificed through gluconeogenesis to provide fuel and preserve biochemical balance. In simple terms, you need to provide protein from a dietary source or your body will steal it from your muscle tissue. The longer you exercise, the more muscle tissue is sacrificed and the more your performance, recovery, and immune system are compromised. During exercise, the wise endurance athlete will make sure that complex carbohydrate and protein intake are both adequate to delay and offset this cannibalization process.

What Kind To Use?

Which protein is best for use before, during, and after exercise has been a subject of much debate. We recommend a combination of both soy and whey protein, used at separate times, to provide the most comprehensive support for an endurance athlete's diet. We believe that whey protein is the premier protein for recovery and enhanced immune system function while soy protein is ideal for fulfilling protein requirements prior to and during endurance exercise. That doesn't mean using soy protein for recovery purposes would be "wrong" or in any way harmful. For optimal benefits though, you'll not find a better protein for recovery and immune system boosting than whey protein. For cardiovascular benefits it's hard to top soy, which is one reason we use it in both Sustained Energy and Perpeteum.

The Benefits of Soy Protein

Soy protein is best used prior to and during exercise, primarily because it has less potential for producing ammonia, a primary cause of muscle fatigue. For general health benefits it's hard to beat soy. Soy protein contains multitudes of health-enhancing phytochemicals. Scientific research has established many connections between soy consumption and lower rates of certain cancers, notably breast, prostate, stomach, lung, and colon. Comparing cancer rates for the U.S. with those of Asian countries (which have soy rich diets) shows some remarkable differences. For instance, Japan has one-fourth the rate of breast cancer and one-fifth the rate of prostate cancer. In China, medical researchers linked the consumption of soymilk to a 50% risk reduction for stomach cancer. Studies done in Hong Kong suggest that daily soy consumption was a primary factor in a 50% reduction in the incidence of lung cancer.

Also, as mentioned in the "Proper Caloric Intake" article, soy protein has a unique amino acid profile that suggests it's the ideal protein to use during endurance exercise. Soy protein is stacked with a substantial proportion of branched chain amino acids (BCAAs), which your body readily converts for energy. BCAAs and glutamic acid, another amino acid found in significant quantity in soy protein, also aid in the replenishing of glutamine within the body without the risk of ammonia production caused by orally ingested glutamine. Soy has high amounts of histidine, which is part of the beta-alanyl l-histidine dipeptide known as carnosine, which has antioxidant/acid buffering benefits. Soy protein also has a high level of aspartic acid, which plays an important role in energy production via the Krebs cycle. Lastly, soy protein has higher levels of phenylalanine than does whey, which may aid in maintaining alertness during extreme ultra distance races.

Hammer Soy

Each scoop of Hammer Soy provides 25 grams of the highest quality 100% GMO (genetically modified organism)-free soy protein, without any fillers, added sugar, and artificial sweeteners or flavoring. Hammer Soy's highly concentrated nature makes it a hunger-satisfying addition anytime, helping you to easily fulfill your daily protein requirements. Add Hammer Soy to juices, smoothies, or other soy-based drinks to make a satisfying and healthy meal. It's also a great addition when making pancake or muffin batter, adding high quality, all vegetable protein to the mixture.

The Benefits of Whey Protein

For enhancing the recovery process, whey protein has no peer. Whey protein has the highest biological value (BV) of any protein source. BV rates the availability of the protein once ingested, and whey is arguably the most rapidly absorbed protein, exactly what you want post-workout. Whey protein's amino acid profile contains the highest percentage of essential amino acids, 25% of which are the BCAAs leucine, isoleucine, and valine, the most important for muscle tissue repair. Whey is also a rich source of two other important amino acids, methionine and cysteine, which stimulate the natural production of glutathione, one of the body's most powerful antioxidants and a major player in maintaining a strong immune system. Glutathione also supports healthy liver function.

Hammer Whey

Each scoop of Hammer Whey contains 18 grams of 100% micro-filtered whey protein isolate, with no added fillers, sugar, and artificial sweeteners or flavoring. The key word here is isolate. Manufacturers supply two forms of whey, isolate and concentrate. Whey protein concentrate contains anywhere from 70% to 80% actual protein, the remainder being fat and lactose. Isolate, on the other hand contains 90%97% protein, with little, if any lactose or fat, making it the purest form of whey protein available. Because isolate contains almost no lactose, even those with lactose intolerance find it an easily digestible protein source. We use only isolate in all our whey containing products.

In addition, each scoop of Hammer Whey contains a whopping six grams of glutamine, a remarkable amino acid. Space limits what we could write regarding the benefits of this extraordinary amino acid, but needless to say, it's essential for endurance athletes in supporting enhanced recovery and immune system function. For more detailed and referenced information, please read Dr. Bill Misner's article "Glutamine: A Conditionally Essential Amino Acid with Remarkable Implications for Health and Performance."

How Much Do You Need?

So how much protein do endurance athletes need to take? Numerous studies have demonstrated that endurance athletes in heavy training need more protein than recreational athletes do. Once it was believed that 1/2 gram of protein per pound of body weight—75 grams for a 150-pound person—per day was sufficient. Today's standards, however, would increase that figure to about 105-110 grams (2/3 to 3/4 grams of protein per pound of bodyweight).

To find out how much you require, multiply your weight in kilograms by 1.4 to 1.7, depending on your exercise intensity. This gives you the amount of protein (in grams) you should consume on a daily basis. (To convert from pounds to kilograms, divide by 2.2) Thus, a 165-pound (75kg) athlete in high training mode should consume about 128 grams of protein daily.

In real-life amounts, to obtain 128 grams of protein you would need to consume a quart of skim milk (32 grams), 3 oz. of tuna (15 grams), 7 oz. lean chicken breast (62 grams), 4 slices of whole wheat bread (16 grams), and a few bananas (one gram each).

Of course, we get protein in some amounts from a variety of foods. But how many of us down the equivalent of a quart of milk, a half-can of tuna, two chicken breasts, and four slices of whole wheat bread every day? Track and record your diet and do some calculating. It takes quite a bit of effort to ensure adequate protein intake, especially for vegetarians and those who avoid dairy products. Remember to include protein intake from Sustained Energy, Perpetuem, and Recoverite in your calculations. If you still come up short, consider additional applications of Hammer Whey and/or Hammer Soy. If you're serious about your performance and also your health, then respect the importance of providing adequate protein in your diet.

Steve Born is a technical advisor for Hammer Nutrition with over a decade of involvement in the health food industry. He has worked with hundreds of athletes—ranging from the recreational athlete to world-class professional athlete—regarding their supplement/fueling program. Steve is a three-time RAAM finisher, the 1994 Furnace Creek 508 Champion, 1999 runner-up, the only cyclist in history to complete a Double Furnace Creek 508, and is the holder of two Ultra Marathon Cycling records. In February 2004 Steve was inducted into the Ultra Marathon Cycling Hall of Fame.

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