Sports Nutrition

Sports Nutrition Unit 8

Role of Diet if Athletics • Maximize their performance • Provide the necessary raw material to allow a good training program to build and run the human machine • Nutritional status, age, genetic background affect nutrient needs • Diets must be individualized • Many myths and fads among athletes

Purpose of Nutrition • Good Nutrition promotes a healthier mind and body • Aids in resistance to illnesses • Energy and vitality are increased • Help athlete feel better and sleep better

Functions of Food • The right combination of nutrients work together in the body to: • Provide heat • Promote growth • Repair tissue • Regulate body processes

The United States Department of Agriculture (USDA) • Developed The Food Guide Pyramid • Provides the following basic dietary guidelines: • Eat a variety of foods • Avoid too much fat, especially unsaturated fat and cholesterol • Eat food with adequate starch and fiber • Maintain a desirable body weight • Avoid too much sodium and sugar

The Food Guide Pyramid • The categories in the pyramid are not considered to be equals • Idea is to get people to eat more of the foods at the base of the pyramid and fewer foods in the groups toward the top • Benefits are many • Lower fat • Increase Fiber • Get more vitamins and minerals in diet • Protect yourself from illness

Breads,Cereals, Rice and Pasta Group • 6-11 servings per day • Foundation of a healthy diet • Good source of complex carbohydrates, which are rich in vitamins, minerals and other nutrients • Ideally 50-60% of the daily calories in a typical American diet should come from complex carbohydrates

Vegetable Group • 3-5 servings per day • Naturally low in fat and high in fiber • Provide crucial vitamins and minerals • One serving consists of: • one cup of leafy vegetables • one-half cup of other vegetables • one potato or ear of corn • Best to eat a variety • Many vegetables help lower a person’s risk of cancer

Fruit Group • 2-4 servings per day • Excellent source of vitamins, minerals, and fiber • Fruits may protect against cancer • Serving of fruit consist: • Medium apple, banana or orange • half cup of chopped, cooked, or canned fruit • three-quarters of a cup of fruit juice

Meat, Poultry, Fish, Dry Bean, Egg and Nut Group • 2-3 servings per day • Excellent source of proteins • Build framework for our muscles, bones, blood, hair, and fingernails and essential for growth and repair • Supply various vitamins and minerals • Serving consists of: • 2-3 oz of lean, cooked mean, fish, or poultry or about the size of your palm • One egg or 1/2 cup dry beans

Milk, Yogurt and Cheese Group • 2-3 servings per day • Milk and yogurt are best sources • Choose products that are low fat or non-fat • One Serving consists: • 8 oz cup of milk • One cup of plain yogurt • 11/2 oz of hard cheese • 1 tablespoon of cheese spread

Fat, Oil, and Sweet Group • Use sparingly • These are placed at the very top of the pyramid so that all Americans will realize they should use them only in very small amounts • Supply little or no vitamins or minerals • Added sugars are often hidden in favorite foods (sweeteners in jam, jellies or syrup)

Basic Nutrients • Chemical substances in food that: • provide energy • act as a building block in forming new body components • Assist in the functioning of various body processes • 6 classes • Carbohydrates, Proteins, Fats, Vitamins, Minerals, and Water

Carbohydrates • Basic source of energy for body heat and body activities • Sugars, starches, and fiber found in fruits, vegetables and grains • Body converts sugars and starches to glucose for energy or to glycogen for energy storage in the liver and muscles • When glycogen stores are full, excess carbohydrates are stored to fat • Fiber is not absorbed but is essential for gastrointestinal functioning • 50-60% of caloric to keep glycogen stores filled • Carbohydrate loading requires 70-80% carbohydrate intake

Proteins • Derived from animal foods-meat, milk, eggs, fish, cheese and poultry • Derived also from soybeans, dry beans, some nuts and whole grain products • Broken down into 20 amino acids • 8 are essential to build and repair tissue • Bodies least efficient source of energy • Body can not store protein, therefore extra is converted into fat • Intake 10-12% of caloric intake

Fats (Lipids) • Fried foods, butter, margarine, salad dressings, oils, mayonnaise are all high sources • Meats, eggs, milk and cheese contain fat too • Provide energy, carry vitamin A and D to cells, and are necessary for normal growth and development • Insulate the body from temperature extremes • Protect and shield body organ’s from impact • Add flavor to our food

Fats cont... • Are necessary, in fact important in diet • Often eat far more than the daily recommended values • 30% of caloric intake is recommended • Most Americans consume 50% or more of their caloric intake from fat • High fat diets are associated with heart disease, hypertension and cancers

Saturated or Unsaturated Fats • Saturated fats tend to raise the cholesterol level of blood • Unsaturated fats are subdivided • Monounsaturated • Are neutral effect on cholesterol • Polyunsaturated • Lower the cholesterol level in blood Fats are not digested as quickly as other nutrients • Considered basic source of muscular energy, since they are used when carbohydrates are depleted

Vitamins • Essential for maintaining good health • Lack of vitamins lead to deficiency conditions • Most cannot be synthesized by body and must be ingested via foods or pills • No single food or food group will supply all vitamins needed by the body • Eat a variety of foods

Fat Soluble or Water Soluble Vitamins • Fat Soluble • Vitamins A, D, E, and K • Emulsified and absorbed in the small intestines • Stored in body cells, especially the liver • Water Soluble • B complex and Vitamin C • Absorbed along with water through the digestive track and dissolve in body fluids • Body does not store well, excess excreted in urine

Minerals • Inorganic substances • Have functions essential to life • Calcium • Necessary for bone strength and muscle contractions • Potassium • Regulates cardiac rhythm • Iron • Assists hemoglobin in the delivery of oxygen to body tissues • Sodium • Essential in maintaining fluid balance • Phosphorus • Needed for strong bones and teeth

Water • Necessities of life • Most of water intake is ingested in the daily diet as fluid or as the fluid contained in solid food

Metabolism • Chemical reactions occurring in the body • Two phases • Catabolism • Reactions which break down complex organic compounds into simple compounds • Provides Energy • Anabolism • Series of reactions whereby small molecules are built into more complex molecules • Form body’s structural and functional components • Requires energy

Sports Nutritional Myths • Calories are calories • False- a variety of nutrients are very important to maintaining a healthy diet • Athlete’s bodies require supplements during training • False-Supplements are only required when the diet is not able to meet the body’s demands • Protein build strong bodies • False-Exercise builds strong bodies. Protein is required to repair tissue but does not build muscle by itself

Sports Nutritional Myths • When we need fluids, we feel thirsty • False- We need water long before we feel thirsty. Constant fluid replacement is required. • Body weight matters most; light athletes are faster • False- Body composition is more important than body weight. Muscle is heavy.

Sports Nutritional Myths • The only food intake that really matters is the food ingested immediately before an important event • False-Nutrition is a long-term pursuit and what you eat weeks before an event can effect your performance • What you eat between and after events doesn’t matter • False-What you eat before, during, and after an event can affect your performance. Post event is very important for rapid recovery

Pre Game Meals • What you eat before you train or compete has four main functions • To help prevent hypoglycemia • To help settle your stomach, absorb some of the gastric juices and decrease hunger • To fuel your muscles with food eaten in advance that is stored as glycogen and food eaten within an hour • To pacify your mind with knowledge that your body is well fueled

Nutrition Benefits for Sport Performance • Eat adequate high carbohydrate meals • To fuel and refuel your muscles • Food eaten an hour before exercise keeps you from getting hungry and maintains your blood sugar, they don’t replenish muscle glycogen stores • If exercising for longer than 60-90 minutes intake carbohydrates that enter bloodstream slowly as they are digested • Rice, pasta, yogurt, oatmeal, bean soup, apples, banana • If exercising for less than an hour snack on foods that digest easily and will settle • Bread, English muffins, bagels, crackers, pasta

Nutrition Benefits for Sports • Limit high-fat proteins like cheese, steak, hamburgers and peanut butter • These proteins take longer to empty from the stomach • Fat delays gastric emptying and cause sluggishness and nausea • Be cautious with sugary foods • Soft drinks, jelly beans, sport drinks etc… • Quickly enter the bloodstream as they are digested • If eat within 15-20 minutes before hard exercise can drop the blood sugar , leaving one tired, light-headed, and fatigue

Nutrition Benefits for Sports • Allow adequate time for food to digest • High calorie meals take longer to leave the stomach than do lighter snacks • Allow 3-4 hours for a large meal to digest, 2-3 hours for a smaller meal and 1-2 hours for a liquid meal and less than an hours for a small snack • If you get jittery and are unable to tolerate any food before an event • Have an extra-large bedtime snack instead of breakfast • Learn how to best fuel your body

Nutrition Benefits Cont… • Always eat familiar foods before competition • Don’t try anything new • New foods always carry the risk of settling poorly, causing intestinal discomfort, acid stomach, heartburn or camps • Drink plenty of fluids • You are unlikely to starve to death during an event, but you might dehydrate • Drink an extra 4-8 glasses of fluid the day before • Drink at least 2-3 glasses of water up to 2 hours before • Dink another 1-3 glasses 5-10 min before start

Pre-Event Training • Tapering • It is wise to gradually decrease the training program about 48 hours before competition • This enables the body to replenish essential stores • Reduces or allows body to eliminate various metabolites that might reduce performance

Alternate Eating Patterns • Food fads are rampant among athletes • NO food, vitamin, hormone or supplement will substitute for sound nutrition and hard work • Vegetarian diet • Primary concern is whether enough protein is consumed • Proteins have essential amino acids and are balanced better in animal products than plant foods • Must carefully plan diet to include all amino acids

Carbohydrate Loading • Endurance athletes whose events last for more than 90 continuous minutes benefit best from carbohydrate loading • Long distance runners, swimmers, bicyclists and cross country skiers • May also benefit athletes involved in sports that require prolonged movements of varying intensities • Soccer, lacrosse, ice hockey, as well as tournament sports

Carbohydrate Loading • Defined as saturating the muscle with carbohydrates- the body’s most efficient source of fuel • 1-3 pounds of water weight is usually gained during carbo-loading, since water is stored with glycogen • 70-80% of calories should come from carbs, 10-15% from fat and 10-15% from protein

Carbohydrate Loading • Load every day, not just before a big event • Daily intake of 60-80% of carbohydrates prevents chronic glycogen depletion • Allows one not only to compete at best, but train at best • Be careful, too many carbohydrates can cause intestinal distress • When you taper training, you do not need to intake additional calories, simply maintain standard intake

Carbohydrate Loading • Include adequate protein • Especially endurance athletes who use some protein for energy • Do not fat overload • Choose wholesome, fiber-rich carbs • Keeps your system running smoothly • Bran muffins, whole wheat bread, bran cereals, fruit • Plan meals carefully • Day before event, eat biggest meal at lunchtime so that the food has more time to digest • Drink extra fluids to hydrate your body • Avoid alcoholic and caffeine beverages- dehydrating

Post Game Meals • What you eat after a hard workout or competition affects recovery • Often athletes do not feel hungry or don’t have time to eat after exercise • Recreational exerciser who works out 3-4 times a week, need not worry about recovery diet • Competitive athletes need to make careful selections of foods eaten after exercise • Football two a days • An athlete with multiple event per meet • Triathlete who trains twice a day • An aerobic instructor who teaches several classes daily

Recovery Fluids • Loose fluids by sweat during exercise • Best replacements are by water, juices and watery foods like watermelons • Determining how much you need to replace • Weigh yourself before and after • The goal is to lose no more that 2% of bw • Any more than 2% are you are dehydrated

Recovery Carbohydrates • Ideally you should consume carbohydrate rich food/beverages within 15 minutes after your workout • Enzymes responsible for making glycogen are most active at this time and will most rapidly replace the depleted glycogen stores • Liquids and solids are equal

Recovery Carbohydrates • Popular carbohydrate rich foods are: • 8 oz or orange juice and medium bagel • 16 oz of cranberry juice • 8 oz fruit yogurt • One bowl of corn flakes with milk and banana • Sport drinks • Be aware that they lack most vitamins and minerals that natural foods have • More expensive

Recovery Protein • Protein can enhance glycogen replacement in the initial hours after hard exercise • Protein Eaten along with carbohydrates is a winning combination

Recovery Electrolytes • When you sweat you lose water as well as minerals such as potassium and sodium • Electrolytes are primarily responsible for muscle cramping and intolerance to heat • You do not need supplements to replenish electrolytes after exercise- standard diet has more than enough to replenish any lost

Rest • Time is necessary for the recovery process of healing and refueling • To completely replace depleted glycogen stores, the muscles may need up to 2 days of rest with no exercise and a high carb diet • Expect to experience soreness on the second day after strenuous exercise that damages your muscle • Quality training is better than quantity training- do not underestimate the power of rest

Fluid Replacement • Water is one of the most important nutrients • You can survive only a few days without it • Drinking too little water or losing too much through sweating inhibits ability to exercise at maximum potential • Free access to water before, during and after activity should be encouraged

Purpose of Water • Water in the blood transports glucose, oxygen and fats to working muscles • In blood, water carries away metabolic waste products • In urine, water eliminates metabolic waste • In sweat, water dissipates heat through the skin, regulating body temperature • In saliva and gastric secretions, water helps digest food • Water helps to lubricate joints and cushion organs and tissues

Fluid Replacement • Plain water is most effective and inexpensive means • Drink small volumes (8 oz) of water frequently (every 15 min) rather than large volumes infrequently • Thirst mechanism is unreliable • Brain does not signal the thirst until you are becoming dehydrated • This significantly hurts your performance • Drink a cold fluid, help hydrate and cool you off

Body Composition • Estimation of a person’s body fat versus body mass • Women have approximately 10% more adipose tissue than do men • Fat is stored in various locations and severs as a protection and insulation to the body • Average Female 22-25% fat • Average Male 12-18% fat • Fat is a must, a goal of 0% is not possible • Less than 6% is unsafe for males • Less than 10% for women leads to amenorrhea

Measuring Body Fat • There are four common methods • Underwater weighing, Skin calipers, BIA and NIR • There is no simple, inexpensive method to date that is 100% accurate • Standard error of most measurement is plus or minus 3% • Body Fat and Ideal Body Weight should be discussed together • Body Fat changes as one • Lose fat, gain muscle, shape up or slim down

Underwater Weighing • Traditionally considered to be most accurate • Subject exhales all the air in their lungs and is then weighed while submerged in a tank of water • Measures body density and is translated mathematically into percent body fat • Errors • Not completely exhaling all air out of lungs • Equipment may not have precise weighing systems

Sports Nutrition