By Kathy Schwab, RD, LD
Courtesy RaceCenter Magazine
Are you confused about what to eat? It's no wonder with so much conflicting advice circulating among athletes looking for a competitive edge. Some nutrition experts say you should eat pasta for endurance, others say pasta makes you fat. Should you eat the "gold-standard" high-carbohydrate, low-fat diet, or will you perform better in the "Zone?" Just in case you are one of the three people who haven't yet heard of the "Zone," the term comes from the best-selling, but controversial book, "Enter the Zone," by Barry Sears. Sears recommends a performance diet that balances protein, carbohydrate and fat in a strict 30:40:30 ratio. The "Zone" diet is higher in protein and fat and lower in carbohydrate than the conventional training diet, which balances the percentage of protein, carbohydrate and fat in a 15:65:20 ratio.
While Sears' theory has become the latest fad among athletes, it has been criticized by the experts. Sears believes that Americans are fatter because we're eating less fat! He has no data to support this conclusion, but cites as "evidence" the fact that obesity in the U.S., has risen over the past 15 years despite a decrease in fat consumption. He implies a cause and effect relationship without producing any evidence that one exists. Seras also believes that carbohydrates cause obesity by activating insulin production. However, this is a simplistic view of how insulin works. Carbohydrates are only converted to fat only if a person chronically consumes excess calories. Sears claims that his diet enhances performance, improves mood and makes it easier to maintain a healthy weight. Again, there is no evidence for these claims, but the diet may aid weight loss simply because it is low in calories.
The conventional high-carbohydrate, low-fat diet has a large body of evidence supporting it, has withstood the test of time, and is the diet recommended by the vast majority of fitness and nutrition experts for fueling athletic performance. This diet helps prevent and reverse high cholesterol, and helps many people lose body fat. However, athletes consuming more than 5,000 calories per day often have trouble eating the sheer volume of food that this diet recommends, while women eating fewer than 1,500 calories per day may not get adequate protein. And many athletes make the mistake of consuming too many of their carbohydrates from refined foods like sugar and white flour, and not enough from fruits, vegetables and whole grains.
The high-protein diet recommended by Sears contains too much protein and fat, and too little carbohydrate for most athletes. Athletes eating 2,000 calories per day (most women) would get only 200 grams of carbohydrate--100 grams fewer than the minimum recommended for athletes--while consuming double their protein needs. Carbohydrate isn't a problem for athletes consuming more than 4,000 calories, because 40% of 4,000 calories provides 400 grams of carbohydrate--comfortably above the minimum requirement. But, the 300 grams of protein a person would consume on this diet provides three times more protein than needed. Excess protein is expensive, promotes dehydration and causes the loss of calcium from bones, contributing to the development of osteoporosis.
However, the answer to "What's the best diet for me?" may turn out to be an unequivocal "it depends." People are biochemically different, with variations in biological ancestry, metabolism and lifestyles. For example, some people who live healthy lifestyles and eat low fat diets battle high cholesterol, while others who up on junk food and never develop a cholesterol problem. Most of us can indulge in desserts when the whim strikes, but people with diabetes have to carefully monitor their sugar consumption. Some people need to limit salt to keep their blood pressure down, while others find their blood pressure unaffected by salt intake. The point is, we are all different, so the idea that there is one best diet for everyone is probably too narrow. The truth is, some people may perform better on a higher protein diet, and others may perform better on a higher carbohydrate diet. The majority of us are probably somewhere in between.
The best way to find your own best diet for peak performance is to experiment. Start keeping a food diary, and after each meal or snack, ask yourself these two questions:
If the answer to both questions is yes, look to see if you're eating too much sugar or refined carbohydrate like cookies, candy, bagels and muffins. If so, you might try cutting down on your sugar intake and replacing refined carbohydrate with unrefined whole grains, fruits and vegetables. You can also try adding a little more low-fat protein to your diet and monitoring how you feel. Good low-fat protein choices include: skinless chicken, turkey, water-packed tuna, egg whites, low-fat cottage cheese or yogurt, dried beans, lentils and tofu.
You may find that small changes in your diet provide the gains in energy and performance you're looking for. You probably don't need to makes dramatic dietary changes. Moderation is a far too underrated concept. Many female athletes consume too little protein in their attempt to avoid fat and might benefit from eating a little more protein without compromising the carbohydrate they need. Athletes consuming more than 4000 calories per day might do better with a slightly higher percentage of calories from fat to help decrease the sheer volume of food they must consume. (Remember, the more fit you are, the more fat you burn, so athletes in the higher calorie ranges can get away with more fat than the rest of us.)
To boost your energy and well-being, make sure to include more vitamin and mineral-rich foods. Eat at least 3 to 4 pieces of fresh fruit and 3 to 4 cups of vegetables every day. Choose only 100% whole-grain breads and cereals. Minimize your intake of refined and processed foods. If you need help figuring out the best diet for your body and your sport, consult a registered dietitian trained in sports nutrition.
Kathy Schwab is a registered and licensed dietitian. She owns NUTRITION FITNESS, a Portland-based nutrition education and consulting firm, and provides personal consultations and group and worksite presentations on topics including sports nutrition and weight management for children and adults. For more Information, contact NUTRITION FITNESS at (503) 760-4617.
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