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Nutrition Basics Proper nutrition is the basis of for physical performance; it furnishes both the fuel for bodily work and the chemicals for extracting and using the potential energy contained within this fuel. Food also provides the necessary elements for the formation of new tissue and the repair of existing tissue. Carbohydrate, fat, protein, vitamins, minerals and water are the six major classes of nutrients. When consumed daily, they provide the essential energy to maintain body functions at rest and during exercise. Energy is supplied by carbohydrate, fat and protein. Carbohydrate and protein supply approximately half the energy that fat supplies: Carbohydrate Protein Fat Alcohol 4 calories per gram 4 calories per gram 9 calories per gram 7 calories per gram (not a source of energy) While normally active adults may require 2000 to 2800 calories for weight maintenance, it is not uncommon to find athletes in training with daily food intake in excess of 5000 calories. Vitamins, minerals and water are necessary for tissue growth, maintaining body structure and controlling body processes. Carbohydrates Carbohydrate is the major source of fuel for the red blood cells and central nervous system. It saves protein from being used for energy and assists in the mobilization of fat for energy. The primary kinds of carbohydrate are sugars and starches, obtained from such foods as fruits, vegetables, breads, pastas and cereals. They are broken down during digestion into glucose, which the red blood cells and central nervous system use for energy. Glucose is also the chief fuel source for the muscles during exercise. When glucose is not used immediately for energy it is stored in the liver as glycogen, which is a long chain form of glucose molecules. Glucose not used as energy or converted to glycogen is converted to fatty acids and stored as body fat. Athletes derive the greatest energy for exercise from carbohydrate. During the first few minutes of exercise, glucose is the major source of fuel. After that the body begins to draw upon its supply of stored glycogen for energy. When these glycogen stores are depleted, the athlete becomes fatigued. Heavy exercise or physical training can deplete the body's muscles of most of its stored glycogen. In order to replenish the muscle glycogen used up training each day, nutritionists suggest eating a diet high in carbohydrate. Generally speaking, 55-60% of an athlete's total caloric intake should be derived from carbohydrate. Fat Fat is a concentrated source of energy in animals as important as carbohydrate is in plants. It supplies essential fatty acids and carries the fat-soluble vitamins A, D, E and K. During digestion, fat derived from foodstuffs is broken down into fatty acids. Body cells, except red blood cells and those of the central nervous system, can use fatty acids directly as a source of fuel. Fatty acids not utilized as energy are stored as body fat. While carbohydrate is the major fuel source for the athlete, fat may also be utilized. However, it takes 20-30 minutes from the time the athlete begins exercise until enough fat is available to serve much good during exercise. When the body begins to burn fat for energy, less glycogen is used. Since there is an abundance of fat stores in the body, this process is important for athletes involved in prolonged endurance-type activities. The drawback of this process is that fat is a less efficient energy source than carbohydrate. It takes more than twice as much oxygen per gram for energy to be released. The most abundant form of fat in the body is in the form of triglycerides. Triglycerides consist of two components, fatty acids and glycerol. There are two forms of fatty acid molecules, known as saturated and unsaturated. Saturated fatty acids are found in prime cuts of meat, poultry skin, shellfish, butter, whole milk products, cocoa butter, coconut oil, palm oil, palm kernel oil, and hydrogenated fats. Unsaturated fats are generally found in plant sources such as sunflower, corn, soybean, sesame, cottonseed oils and olives, avocados, peanuts, cashews and their oils. They may also be found in omega-3 fatty acids found in fish. Nutritionists suggest that fat constitute approximately 25-30% of a person's total caloric intake, and limiting the amount of fat calories derived from saturated fatty acids to 10% or less. Although the unsaturated fats can lower cholesterol, it is recommended that they do not increase total fat intake to greater than 30%. Protein Protein is not used as a source of fuel under most circumstances. However, it is essential for building all cells in the body. Protein is necessary to: 1. 2. 3. 4. Repair body tissues Make hemoglobin, which transports oxygen to the tissues Form antibodies in the bloodstream Produce enzymes and hormones Protein is composed of the linkage of many smaller molecules known as amino acids. When protein is consumed and digested, it is broken down by enzymes into the amino acids from which it was originally built, and used to build muscle, hemoglobin, enzymes or hormones. Amino acids that are not used in these processes are stored as body fat. Of the 22 amino acids required by the body, 8 (9 in infants and stressed older adults) cannot be synthesized in the body and must be provided pre-formed in foods. They are referred as essential amino acids. The remaining amino acids that can be manufactured within the body are called non-essential amino acids. This does not mean that they are not important, but rather that they can be synthesized in the body from compounds ordinarily available. Protein nutrients that contain all of the essential amino acids in the correct form, they are termed complete proteins (higher quality). An incomplete protein (lower quality) lacks one or more of the essential amino acids. Sources of the complete proteins are mainly of animal origin (eggs, milk, meat, fish and poultry) whereas most vegetable proteins (lentils, dried beans and peas, nuts and cereals) are incomplete proteins. Despite the beliefs of many athletes, there is no benefit from eating excessive amounts of protein. In fact, excessive protein will lead to storage of fat below the skin and may place great strain on the liver. On the average, a daily intake of 0.7 to 0.9 g of protein per lb body weight is recommended. This level of dietary consumption generally constitutes approximately 20% of total caloric intake. Vitamins Vitamins are organic substances needed by the body in small amounts. They help control the growth of all body tissues and are necessary for the release of energy in the body. The body cannot manufacture vitamins; thus, they must be supplied in the diet or through manufactured supplements. A well-balanced diet of various meats, cereals, fruits, vegetables and milk will provide a person with a sufficient supply of vitamins to meet the body's needs. Because vitamins can be used repeatedly in metabolic reactions, the vitamin needs of athletes are generally no greater than those of sedentary people. Table 2.1 Water-soluble vitamins, their dietary sources, and major bodily functions Vitamin Niacin Panthotenic Acid Vitamin B-1 (Thiamine) Folacin Vitamin B-6 (Pyridoxine) Vitamin B-2 (Riboflavin) Vitamin B-12 Legumes, green vegetables, whole-wheat products Biotin Synthesis and breakdown of amino acids Vitamin C Muscle meats, eggs, dairy products (not present in plant foods) Dietary Sources Legumes, vegetables, meats Formation of red blood cells, RNA, and DNA Citrus fruits, tomatoes, green peppers, salad greens Normal growth, maintenance of neural tissue, formation of red blood cells Pork, organ meats, whole grains, legumes Widely distributed in foods Liver, lean meats, grains, legumes (can be formed from tryptophan) Major Body Functions Involved in energy metabolism Meats, vegetables, whole-grain cereals Involved in energy metabolism Widely distributed in foods Involved in energy metabolism Involved in energy metabolism Fat synthesis, amino acid metabolism, glycogen formation Maintains intracellular matrix of cartilage, bone and dentine; collagen synthesis Table 2.2 Fat-soluble vitamins, their dietary sources, and major bodily functions Vitamin Vitamin A Vitamin D Vitamin E Vitamin K Dietary Sources Body Functions Beef, liver, carrots, spinach, eggs, milk Vision, growth Eggs, dairy products, fortified milk, margarine (also from sunshine) Bone growth, absorption of calcium Seeds, green leafy vegetables, margarine, shortenings Protects cell structures Green leafy vegetables, vegetable oils Blood clotting Minerals Minerals are needed for maintaining body structure and controlling body processes. They are inorganic elements that combine with organic compounds in the body. The most important minerals are those found in enzymes, hormones and vitamins. In the body, minerals are categorized as major minerals - those present in large amounts and have known biologic functions, and trace minerals - those present in small quantities. A well-balanced diet will supply sufficient amounts of minerals. An abundance of minerals is worthless to the body and may be hazardous. Water Although water does not contribute to the nutrient value of food, it is probably the most neglected nutrient among athletes. The energy content of foods tends to inversely relate to the amount of water they contain. That is, foods high in water content are low in calories. The human body is approximately 60% water. Thus, it is probably the most important substance essential to human life. In the body, water serves as: 1. 2. 3. 4. 5. A solvent for digestion, helping the chewing and softening of food A solvent for the elimination of waste products A major constituent of blood A lubricant in the joints, and between internal organs A coolant for the body The ability of water to cool the body is extremely important for athletes. During exercise, sweat the evaporation of sweat produced by the body serves to keep the body from over-heating. The amount of water lost through sweat depends on the intensity of exercise and the environmental temperature. The relative humidity of the surrounding air also determines the efficiency of sweating. When relative humidity is high the water vapor in the air inhibits the evaporation of sweat. The body is more likely to overheat under these conditions. It is essential that athletes drink sufficient fluids before, during and after exercise. People are usually dehydrated by the time they feel thirsty. Therefore it is important to drink fluids before you train or compete. Table 2.3 Important minerals, their dietary sources and major bodily functions Mineral Calcium Milk, cheese, dark-green vegetables, dried legumes Bone and tooth formation, blood clotting, nerve transmission Phosphorous Milk, cheese, meat, poultry, grains Bone and tooth formation, electrolyte balance Meats, milk, many fruits Electrolyte balance, body water balance, nerve function Common salt, seafood Electrolyte balance, formation of gastric juice Common salt, seafood Electrolyte balance, body water balance, nerve function Whole grains, green leafy vegetables Activation of enzymes, protein synthesis Eggs, lean meats, legumes, whole grains, green leafy vegetables Formation of hemoglobin and red blood cells, energy metabolism Zinc Liver, vegetables, milk, egg yolk Important for digestion, growth Iodine Dietary Sources Fish, dairy products, vegetables Body Functions Important for thyroid gland function Potassium Chlorine Sodium Magnesium Iron Guidelines For The Athlete Breakfast Your body and mind both need fuel to achieve maximal performance levels. Muscles need fuel to contract and carry out the motor skills necessary to your sport. Your brain needs fuel to maintain mental alertness and the ability to make complex decisions during competition. Without a good breakfast, your body and mind will be like a car running on fumes by the middle of the day. Start the day with a wholesome breakfast. You will be alert during class and have the energy for daily workouts. If you are on the run, some quick-fix breakfast ideas include: 1. 2. 3. 4. 5. 6. 7. 8. yogurt bananas blender drinks raisins and peanuts bagels bran muffins graham crackers pita bread stuffed with light cheese, cottage cheese, peanut butter, etc Cereal is a convenient, carbohydrate-rich breakfast staple. Many cereals are excellent sources of fiber and are often fortified with iron. By adding low-fat milk to cereal you also get a meal rich in calcium and low in cholesterol. Add a glass of orange juice or eat fruit high in vitamins A and C with cereal to enhance iron absorption. Remember to choose low-fat, low-salt cereals to maintain a healthy lifestyle. Caffeine Athletes often inquire about the reported ability of caffeine to in increase endurance. However, research in this area has been inconclusive. Moderate amounts of coffee or tea (1-2 cups) are unlikely to harm a healthy person, but there are substances in coffee and tea can interfere with the absorption of iron. 1 cup of coffee can reduce by 40% absorption of a hamburger's iron. Additionally, caffeine stimulates gastric juices and may cause "coffee stomach." Fast Foods In today's hustle and bustle world, many of us are forced to eat on the run. Unfortunately, we often settle for fast foods rather than wholesome foods. Fast foods are usually high in fat and generally lack fiber content of wholesome foods. They may be low in nutrients, especially vitamins A and C, and are often high in salt. Along with these hamburgers, fried chicken tacos, etc. we also choose sugar-laden soft drinks with zero vitamins and minerals or fat-laden shakes with limited nutritional benefits. If you must eat at a fast food restaurant, choose foods high in carbohydrates and low in fat. Ask for an extra bun with a grilled chicken sandwich, for example. Better yet, try to plan ahead and carry carbohydrate-rich bagels and fruit with you to school for snacking between classes. Pre-event Nutrition There are several reasons for having a nutritionally sound pre-event meal: 1. 2. 3. 4. To help prevent hypoglycemia (low blood sugar), which brings about fatigue in the muscles and reduces mental alertness To help settle your stomach; we all know that an anxious stomach can take away from our concentration from the matters at hand To fuel the muscles and ensure that you can "go the distance" To pacify the mind; after having a good pre-game meal you will know that body is well-fueled Each of us is a different animal and we must each realize what makes us tick. It is important that you determine what particular food is right for you. However, the following guidelines will ensure that everyone is ready to perform at a high level: 1. 2. 3. 4. 5. 6. Choose high-starch, low-fat foods Avoid sugary foods, which lead to hypoglycemia Allow adequate time for food to digest Liquid foods leave stomach faster than solid foods (e.g., blended breakfast) Eat familiar foods before a competition Drink plenty of fluids Recovery Foods Fluid Replacement Following a hard workout, game or match it is essential that you replace the fluids lost by sweating. Some of the best sources replacing sweat losses are: 1. 2. 3. 4. Juices Water Watery foods such as watermelon, grapes, soups High-carbohydrate sports drinks (supply fluids, but minimal vitamins and minerals) Examples of watery foods include: 1. 2. 3. 4. 5. 6. Food Lettuce Cucumber Tomato Orange Banana Chicken % Water 95% 95% 95% 85% 75% 60% Compare these foods to the following: 1. 2. Food Cheese Cookie % Water 35% 5% Replacement of Fuel Stores You should consume carbohydrate-rich foods and beverages within 1-4 hours after competition or workout. A good target intake is 0.5 grams of carbohydrate per pound of body weight within first two hours and same amount two hours later. For example, a 130-pound person should attempt to attain 130 x 0.5 or 65 grams of carbohydrate (260 calories). This amount can be easily be achieved with: 1. 2. 3. 4. 1 cup of orange juice and a bagel 2 cups of cranberry juice 1 12-oz can of soft drink (non-diet) and 8 oz of fruit juice 1 bowl of cereal and a banana Sports drinks such as Gatorade or Exceed have approximately 10 grams of carbohydrate per cup, but they lack the vitamins and minerals found in wholesome foods. Electrolytes In addition to the water lost when you sweat, some minerals (electrolytes) such as potassium and sodium are also lost from the body. These minerals help your body function normally. Fortunately, these losses can be replaced by choosing the right recovery foods and fluids after your workout or competition. The following guidelines help to ensure sound recovery from your event. Potassium can easily be replaced with the following foods: 1. 2. 3. 4. Potato Yogurt Banana Orange Juice 750 mg 500 mg 500 mg 420 mg Sodium 1. 2. 3. 4. Yogurt Muffins Pizza Spaghetti While sports drinks replace the fluids lost during workouts or competition and are a source of carbohydrates, they have little, if any vitamins or minerals. Eight ounces of Gatorade contains only 24 mg of potassium while eight ounces of Exceed contains only 45 mg of potassium. Thus, a combination of juice and water would provide a fluid replacer that is quickly absorbed by the body, a greater source of carbohydrate and more vitamins and minerals than commercial sports drinks It is also essential that you rest after intense exercise or competition. All the sound nutritional advice in the world will not help you if you do not allow your muscles and your mind to recover from tough workouts or competition. Salads Salads can be a great source of nutrition for the athlete, but they should not be the only things the athlete eats. Sound nutrition for the athlete includes foods from all four major food groups. A nutritious sports salad should be filled with colorful, vitamin-rich vegetables, carbohydrates, protein-rich beans, and topped with "lite" dressing. Snacks Snacks do not have to be thought of as the "four-letter word" of nutrition. Snacks are simply defined as small meals and can be of great importance to the athlete. A nutritious mid-morning snack can give you the energy to keep your mind attentive during class. A sound mid-afternoon snack will provide the energy for your afternoon workout. An evening snack can give you extra calories if you are trying to gain some weight. The athlete's snacks should be high in carbohydrate and low in fat. Some examples of snacks for the athlete include: 1. 2. 3. 4. 5. 6. 7. 8. 9. Dry cereal Popcorn Muffins Fruits Frozen fruit bars Crackers Bagels Baked potatoes Nuts and seeds It is vitally important that you do not substitute snacks for regular meals. Remember, snacks are small meals to be eaten in addition to your regular meals and can be used strategically to help your performance. Dietary Guidelines ANJON Systems, Inc., South Bend, Indiana 1. Choose daily servings from the five major food groups 2. Eat three meals per day. When weight gain is desired, there should be an addition of two to three snacks. 3. Cut down on the foods that are high in fat: Red meats (steak, hamburger, franks, luncheon meats) Pork products Whole milk, ice cream, cream and cream sauce Cheese and cheese sauce Butter and margarine Mayonnaise and Miracle Whip Oils of all kinds (for cooking or salads) Salad dressings French fries or other fried potatoes such as chips 4. Suggestions to lower fat intake Buy lean cuts of meat and trim all excess fat Keep meats to a moderate serving, substituting fish and poultry Don't fry foods; bake, broil, boil, poach, steam or barbecue Use all fats sparingly Use dairy products made with whole milk sparingly Avoid the use of products packed in oil Substitute low calorie foods that will help lower your fat intake 5. Increase intake of complex carbohydrates and grain products Breads, rolls Cereals Pancakes, waffles French toast Pasta, rice Vegetables Fruit and fruit juices 6. Refined sugars should not replace balanced meals Foods that are high in refined sugar have a lower vitamin and mineral content Many sweets are also high in fat (chocolate candies, pies, cakes) 7. Water intake should be six to eight glasses a day Stock Up On Good Nutrition Cupboard Refrigerator Freezer Spaghetti Rice Ramen noodles Potatoes Wheat crackers Ry-Krisp Spaghetti sauce Minced clams Tuna Canned salmon Kidney beans Peanut butter Bran flakes Oat bran Muesli Raisins "Lite" cheese Parmesan cheese Low-fat cottage cheese Low-fat yogurt Eggs Bananas Carrots V-8 juice English muffin Pita bread Multigrain bread Orange juice concentrate Broccoli Spinach Winter squash Cut up chicken Extra lean hamburger Ground turkey How Many Calories? The body requires a certain amount of energy to maintain its basic functions (circulation of blood, breathing, etc.). This is known as basal metabolism. Additional calories are necessary for the body to perform physical activities such as walking, jumping, even writing notes in class. The procedure outlined below will estimate how much energy (calories) the body needs to maintain current weight. Each day, about 10 calories per pound of body weight are needed for basal metabolism. The amount of energy needed for physical activities depends on how active an individual is. Below are three general classifications of physical activity and the percentage of basal metabolism required for each physical activity level. Activity Level Sedentary: Physical activity limited to walking and sitting Percentage Above Basal 30% Moderately Active: Engaged in physical activities involving standing and walking 50% Very Active: Regular or daily participation in sports or other vigorous physical activities 70% - 80% To estimate total daily caloric needs, add estimated physical activity calories to estimated basal calorie needs. For example: A 150-pound very active adult requires: Basal calories 150 x 10 = 1,500 Activity calories .70 x 1500 = 1,050 Total calories to maintain current weight 1,500 + 1,050 = 2,550 If you are looking to gain weight the healthy way, consume an additional 500 - 1000 calories per day above that required to maintain your weight. For example: A 235-pound very active athlete requires: Basal calories 235 x 10 = 2, 350 Activity calories .70 x 2350 = 1,645 Total calories to maintain current weight 2,350 + 1,645 = 3,995 Consuming approximately 4,500 - 5,000 calories per day will help this athlete increase weight at a rate of about one pound per week. WHAT IS THE BEST WAY TO GAIN BODY WEIGHT? Eating habits must change to meet the dietary guidelines. There must be a sound nutritional base. Once this is accomplished, the addition of liquid supplements such as Ensure Plus can be used to elevate calories to the desired level. This is the correct way to gain muscle tissue and not fat. HOW DO I REDUCE BODY WEIGHT? Again, fallow the dietary guidelines to balance the diet. To estimate your daily caloric requirements, refer to the chart below: ESTIMATED DAILY CALORIC INTAKE IN RELATION TO CURRENT BODY WEIGHT (During Hard Physical Workouts) NOTE: Percentages of macronutrients should be 55-60% complex carbohydrates, 20-25% fat, and 15-20% protein. (Refer to Dietary Guidelines). WEIGHT LBS. 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 REDUCE 1,530 1,720 1,990 2,100 2,290 2 480 2 670 2 860 3,050 3,240 3,430 3,620 3,810 4,000 4,190 4,380 4,570 4,760 4,950 MAINTAIN 2,280 2,470 2,660 2,850 3,040 3,230 3,420 3,610 3,800 3,990 4,180 4,370 4,560 4,750 4,940 5,130 5,320 5,510 5,700 INCREASE 3,030 3,220 3,410 3,600 3,790 3,980 4,170 4,360 4,550 4,740 4,930 5,120 5,310 5,500 5,690 5,880 6,070 6,260 6,450