Sunday, August 10, 2008

Do Vegetarian Diets Help or Hinder Endurance Athletes?

The number of vegetarians in the United States has been steadily increasing over the years. Most people adopt a vegetarian lifestyle for its numerous health benefits. A vegetarian is defined as someone who omits all animal products (including fish, chicken and turkey) except for dairy products and eggs.

In various polls conducted by the Vegetarian Resource Group, it was reported that the number of vegetarians in the U.S. grew from approximately one percent in both 1994 and 1997, to approximately 2.5 percent in 2000. In 1999 the Vegetarian Resource Group also reported that when American adults eat meals away from home, 5.5 percent of them always order a dish without meat, fish or fowl, and 57 percent of the population sometimes, often or always orders a vegetarian item.

Studies show that vegetarian diets are linked to a reduced risk of various diseases such as high blood pressure, kidney disease, heart disease and certain types of cancer. Although other common aspects of a vegetarian lifestyle, like abstinence from smoking and drinking, or higher levels of physical activity, may account for the decreased risk of disease, a vegetarian diet definitely has its benefits. Most Americans eat far too much meat and not enough fruits, vegetables and whole grains. By omitting meat from the diet, more room is available to add healthful foods.

But is it a good idea for an endurance athlete to follow a vegetarian diet? Can runners, cyclists, swimmers, in-line skaters and the like benefit from omitting meat from their diet? It all depends on the nutritional adequacy of the diet!

Although most Americans get more than enough protein in their diet, sometimes it is difficult for a strict vegetarian or vegan (those who omit all animal products from their diet, including dairy and eggs) athlete to obtain enough protein if they are not careful in planning their meals. Protein is important for endurance athletes in order to rebuild and repair damaged muscle tissue. The Recommended Dietary Allowance (RDA) for protein is 0.8 grams per kilogram of body weight. Therefore, a 160-pound (72.7 kg) male would need about 58 grams of protein day, while a 140-pound (63.6 kg) female would need only 51 grams a day to meet the RDA. This amount would be relatively easy to achieve, even if following a vegan diet. But if you are an endurance athlete, the RDA doesn't quite cut it.

The protein recommendation for an endurance athlete is about 1.2 to 1.8 grams per kilogram of body weight, so now our 160-pound male that is involved in endurance athletics would need between 87-131 grams of protein a day, and the 140-pound female athlete would need 76-115 grams a day, substantially more than the RDA. For a vegetarian that includes dairy products and/or eggs in their diet, this amount would still be relatively easy to obtain, but a vegan would need to make wise food choices to make sure they had adequate protein in their diet. Good, high protein choices for vegans include beans (legumes), peanut butter, nuts and seeds, and soy products. Even some non-dairy "cheeses" contain a good amount of protein, although most contain casein (a milk byproduct), which the majority of vegans avoid. Many grains are also relatively high in protein, for example a large bagel has about 10 grams, and a cup of pasta has seven grams. Be advised that any extra protein calories, just like extra carbohydrates and fat calories, will be stored as fat.

As long as protein needs are met, athletes can be at an advantage if they adopt a vegetarian diet because they tend to be higher in carbohydrates than a non-vegetarian diet. Carbohydrates are essential for maximum athletic performance because only carbohydrates can be stored in the muscle as glycogen. Glycogen is what fuels muscles, and when these stores are depleted and not replenished, fatigue can set in. Athletes should strive to consume about eight grams of carbohydrates per kilogram of body weight. For a 160-pound male athlete this would be about 580 grams per day, and for a 140-pound female athlete this would equal about 510 grams a day. Good carbohydrate choices include fruits, vegetables, pasta, rice, cereals and other grains. These sources of carbohydrates also supply the body with much-needed fiber.

Iron is an important nutrient, especially for athletes, because it is a component of hemoglobin. Hemoglobin is the substance that transports oxygen within the red blood cells. Vegetarian and vegan athletes can obtain iron from a variety of plant foods such as green leafy vegetables, legumes and nuts, as well as fortified foods such as cereals and soymilk. The iron that comes from plant sources, dairy products and eggs isn't absorbed by the body as well as the iron from meat, fish and poultry, so vegetarians and vegans (especially females) need to make sure they consume foods rich in iron.

A vegetarian diet that includes an abundance of fruits and vegetables can also be beneficial to an athlete because of the high antioxidant content of the diet. Intense physical activity can cause oxidative stress within the body, and the antioxidants in fruits and vegetables can help combat this stress. Studies have shown that a high intake of antioxidant nutrients can lead to a decrease in muscle soreness after exercise. Although it is best to obtain these nutrients from your diet, supplementing your diet with the antioxidant nutrients, vitamin C (500 to 1,000 milligrams) and vitamin E (200 to 400 international units) may enhance your performance. Fruits and vegetables also have a very high water content, which can help add to your total daily fluid needs.

Although dietary guidelines suggest that fat should comprise less than 30 percent of your diet, it is recommended that athletes go a little lower, to about 25 percent, to make room for a higher proportion of carbohydrates. A vegetarian diet is typically lower in fat than a non-vegetarian diet, especially saturated fat. Saturated fats, like those found in meat and full fat dairy products, can raise your blood levels of "bad" cholesterol, which leads to an increased risk of heart disease. Not exactly what you want as an endurance athlete! No more than 10 percent of calories should come from saturated fat, for a 2,000-calorie diet, this is about 20 grams. But some fat in your diet is essential; fat has many functions, including the transport of fat-soluble vitamins. Because most vegetable sources of fat are unsaturated fats, with the exception of palm and coconut oils, and most animal sources are saturated, a vegetarian diet with low-fat dairy products can be advantageous in reducing the risk of heart disease.

Last but not least, it is important that an athlete consume enough calories to fuel their body! Vegetarian diets tend to be lower in calories than non-vegetarian diets, which could be a plus for someone looking to lose weight. But, if you wish to maintain your weight, it is important to consume enough calories before, after and possibly during (if it lasts longer than 90 minutes) exercise. A vegetarian diet than includes a variety of vegetables, legumes, nuts, fruits and grains can supply an endurance athlete with enough calories to keep them going. While a non-vegetarian diet isn't going to hinder athletic performance, a vegetarian diet can have some advantages when it is properly planned. A breakfast of toaster pasties, a lunch consisting of cheese pizza and French fries, and then macaroni and cheese for dinner could also be considered vegetarian, but will not be of any benefit in your athletic endeavors! But a well-planned vegetarian diet can supply an optimal ratio of nutrients that can help boost your performance!

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