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Chapter 5: Nutritional Considerations © 2007 McGraw-Hill Higher Education. All rights reserved. Nutrients • Diet – Foods regularly eaten; does not always mean losing weight • Nutrition – Science of food substances & what they do in the body • Nutrients – Specific food substances • Nutrients have 3 roles – Grow, maintain and repair all body cells – Regulate body processes – Supply energy for cells © 2007 McGraw-Hill Higher Education. All rights reserved. 6 Classes of Nutrients – Carbohydrates (CHO) – Protein – Fat Macronutrients – Vitamins – Minerals – Water Micronutrients © 2007 McGraw-Hill Higher Education. All rights reserved. Carbohydrate (CHO) • Most efficient energy source • Makes up at least 55-60% of total caloric intake • Simple – Refined sugars with fewer essential nutrients – honey, yogurt, fruit juice, candy, desserts – Digested quickly • Complex – Have more nutrients and fiber & take longer to digest – Whole grain bread, cereals, rice, vegetables • Fiber © 2007 McGraw-Hill Higher Education. All rights reserved. Carbohydrate cont. • Should eat more complex carbohydrates than simple • Simple carbohydrate intake should consist primarily of fruits, yogurt or milk not candy and desserts • Foods high in refined sugar are typically low in nutrients © 2007 McGraw-Hill Higher Education. All rights reserved. Fats • Most concentrated source of energy • Serves to make food flavorable and contain fat soluble vitamins (A, E, D, K) • Needed for hormores, hair and skin development • Fats should be less than 25% of caloric intake • High fat diets lead to obesity, certain cancers and coronary heart disease. © 2007 McGraw-Hill Higher Education. All rights reserved. Proteins • Required for growth, maintenance, and repair of the body • Helps repair/build muscles • Aid with enzyme, hormone, and enzyme production • Provides little energy • 12-15% of daily caloric intake • Red meat, chicken, fish, eggs, beans, peanut butter © 2007 McGraw-Hill Higher Education. All rights reserved. • Amino Acids – – – – Building blocks of protein 20 amino acids compose the majority of body protein Body can make most of them Essential Amino Acids – can’t be made by body, so must be eaten – Animal products contain essential amino acids – Plant sources contain incomplete amino acids © 2007 McGraw-Hill Higher Education. All rights reserved. Vitamins • Vitamins (13) serve as regulators in many body processes • Fat soluble – Fat soluble vitamins A, D, E , K – Will be stored in the body – Found in fatty portion of foods and oils • Water soluble – – – – Vitamin C, B-complex vitamins Help to regulate metabolism but cannot be stored Each serves a series of roles Excess are secreted in urine daily © 2007 McGraw-Hill Higher Education. All rights reserved. Vitamins • • • • Vitamin D – becomes activated by sunlight Vitamin K – helps with blood clotting Vitamin C – helps improve immune system Folic acid – important during pregnancy © 2007 McGraw-Hill Higher Education. All rights reserved. • Anitoxidants – May prevent premature aging, cancers, heart disease and other health problems – Include vitamins A, C, E – Found in a number of dark green, deep yellow and orange fruits and vegetables • Vitamin Deficiencies – Illness that results from a deficit in a particular vitamin/mineral – Are avoidable if an adequate diet is consumed © 2007 McGraw-Hill Higher Education. All rights reserved. Minerals • • • • 20 minerals have essential roles in the body Many are stored in liver and bones Help with strong bones and teeth Calcium is most abundant mineral in body – – – – Calcium/phosphorus – strong bones Iron – oxygen transportation in blood Magnesium – energy supplying reactions Sodium and Potassium – nerve conduction © 2007 McGraw-Hill Higher Education. All rights reserved. Water • Most essential nutrient • Most abundant nutrient – 60% of body • Essential for all processes & regulates body temp • Need 8 cups/day or • Drink number of ounces that equals ½ your body weight – 100 pound person needs 50 oz/day • Dehydration – lack of water can lead to overheating, illness and death © 2007 McGraw-Hill Higher Education. All rights reserved. Electrolytes • • • • • Some minerals are electrolytes Sodium, potassium, magnesium, and calcium Sweating can lead to loss of electrolytes Helps maintain hydration, decrease cramping Drinking sports drinks – Gatorade or Powerade will provide extra electrolytes during activity © 2007 McGraw-Hill Higher Education. All rights reserved. Nutrient Deficiency Diseases • Osteoporosis – Low calcium/phosphorus – Bones are fragile and break easily – More common in women • Anemia – Low iron – Decreases ability of blood to carry oxygen – Feel tired and weak especially with exercise © 2007 McGraw-Hill Higher Education. All rights reserved. © 2007 McGraw-Hill Higher Education. All rights reserved. MyPlate • Goal is to provide visual representation of ideal diet. • Half of your plate should be fruits and vegetables. • The other half of your plate should be protein and grains, with grains being slightly more than protein. © 2007 McGraw-Hill Higher Education. All rights reserved. • 5 Healthy Food Groups – – – – – Grains Fruits Vegetables Milk Meat and Beans • Oils © 2007 McGraw-Hill Higher Education. All rights reserved. Nutrient Dense Junk Food/Empty Calories High nutritional value in relationship to number of calories Low nutritional value in relationship to the number of calories High nutrients Low calories Low nutrients High calories © 2007 McGraw-Hill Higher Education. All rights reserved. Production of Energy From Foodstuffs • Energy is produced with breakdown of CHO, fat or protein • Short-term, high-intensity activity – CHO • Endurance activity – CHO and fat • Protein usually less than <5% of energy © 2007 McGraw-Hill Higher Education. All rights reserved. © 2007 McGraw-Hill Higher Education. All rights reserved. Dietary Supplements: Myths and Misconceptions – Increase in activity does not mean more vitamins are needed – Supplements do not always help performance – Placebo effect = phychological or mental boost © 2007 McGraw-Hill Higher Education. All rights reserved. • Little research done on some supplementss – FDA oversees supplements – Has only banned ephedrine • Before using supplements ask a MD or nutritionist • Coaches should not provide or handout any supplements – May break the law © 2007 McGraw-Hill Higher Education. All rights reserved. Vitamin Supplements • If you eat a balanced diet you probably don’t need a vitamin • Taking more than the DRI level will not improve performance • Extra water soluble vitamins will be excreted with urine • Fat soluble vitamins (A, D, E, K) will be stored in the body – can reach harmful levels © 2007 McGraw-Hill Higher Education. All rights reserved. Mineral Supplements • Calcium and iron tend to be low • Calcium – most abundant mineral in body – – – – Needed for strong bones and maintenance Young adult requires 1000mg/day Females tend not to get enough calcium in diet Exercise and weight bearing activities also increase bone strength – Milk is best source • Lactose intolerant – Don’t have enzyme lactase and can’t digest milk – Causes upset stomach and gas © 2007 McGraw-Hill Higher Education. All rights reserved. • Iron Supplements – Iron deficiency is common in females – Low iron = feel weak and tired – Difficult for blood to carry oxygen © 2007 McGraw-Hill Higher Education. All rights reserved. • Protein Supplements – Most don’t need protein supplements – Need about 1-1.5g per kg of body weight for increasing muscle mass – Usually have more than this is diet • Creatine Supplements – – – – Naturally made in kidneys, pancreas and liver Found in meat and fish Role in metabolism Two types (free creatine and phosphocreatine) © 2007 McGraw-Hill Higher Education. All rights reserved. – Positive effects • • • • increase intensity of workouts lactic acid buffer stimulates protein synthesis decreases total cholesterol and total triglycerides and improves HDL-LDL ratio • increases fat free mass – Negative effects include weight gain, muscle cramping and gastrointestinal disturbances and renal dysfunction – Not a banned substance, however, distribution by NCAA institutions is banned © 2007 McGraw-Hill Higher Education. All rights reserved. • Herbs – Natural alternatives to drugs and medications – Safe to ingest as natural medicines with few side effects (occasional allergic reaction) – Don’t need to eat with food – Must be careful because there is no regulating agency or governmental control – Must tell your doctor if you take any herbs or natural supplements © 2007 McGraw-Hill Higher Education. All rights reserved. • Ephedrine – Stimulant used in diet pills, illegal recreation drugs and legitimate OTC medications – Similar to amphetamine – Banned by FDA in 2003 – Banned in athletics – Known to cause • • • • Heart attack, stroke, fast heart beat Paranoid psychosis, depression, convulsions, coma Fever, vomiting, palpitations, hypertension Hypertension and respiratory depression © 2007 McGraw-Hill Higher Education. All rights reserved. Popular Eating and Drinking Practices • Caffeine Consumption – Central nervous system stimulant – carbonated beverages, coffee, tea, soda, chocolate – Increase alertness and decrease fatigue – Too much causes nervousness, irritability, increased heart rate and headaches – Addictive – Withdrawal may cause headache (HA) © 2007 McGraw-Hill Higher Education. All rights reserved. • Alcohol Consumption – Provides energy for the body • 7 calories per gram of alcohol – Little nutritional value – Central nervous system depressant • decreases coordination, slows reaction time, decreases mental alertness • increases urine production (diuretic effect) – Not recommended for use by athletes before, during or after physical activity © 2007 McGraw-Hill Higher Education. All rights reserved. Vegetarianism • Most of diet is from plant sources • May not eat any animal products – Meat, eggs, cheese • Economic, philosophical, religious, cultural, or health reasons • Diet must be carefully planned, so there are no deficiencies © 2007 McGraw-Hill Higher Education. All rights reserved. Pre-game Nutrition • Should be eaten 4 hours before activity – Gives time for food to leave stomach & upper GI • Food eaten days before is more important than pre-game meal • Purpose to provide quick energy and blood sugar • Liquid meals/drinks are often a good option – reduces dry mouth, abdominal & leg cramps, nervous defecation and nausea • Eat what the individual usually eats; don’t try new foods © 2007 McGraw-Hill Higher Education. All rights reserved. Fast Foods • America is the world of fast food junkies • Often meal of choice during travel • High Fat – Usually 40-50% of the calories are from fat • Portion sizes • Read nutritional information • Pick more healthy options – Grilled chicken, no mayo, fruit, small french fries © 2007 McGraw-Hill Higher Education. All rights reserved. Low Carbohydrate Diets • Numerous versions – Most replace CHO intake with protein and fat • Unused CHO is quickly turned into fat – CHO increases insulin production = insulin encourages fat to be deposited & triggers a hunger response © 2007 McGraw-Hill Higher Education. All rights reserved. Glycogen Supercompensation • “Carb loading” • Glycogen is stored energy • Increase muscle and liver glycogen stores before an endurance activity • Glycogen is easily stored if you eat immediately after exercise – the muscle is able to absorb or hold more glycogen at that time © 2007 McGraw-Hill Higher Education. All rights reserved. • Takes 6 days to Carb load – 5&6 days before event : train hard and decrease CHO intake – 3&4 days before: decrease training at increase CHO intake - 50-100% – 1&2 days before: no activity and normal diet; no glycogen will be used • Benefits aren’t clearly known • Do not try more than 2-3 times per year • Ideal for extreme endurance events © 2007 McGraw-Hill Higher Education. All rights reserved. Fat Loading • Idea was it would provide a better energy source since fat is the most concentrated form of energy • It did not work © 2007 McGraw-Hill Higher Education. All rights reserved. Ideal Body Weight • Height/weight charts – Not most accurate; don’t take body type into account • Body Mass Index (BMI) – Considers age, gender, height, and weight • Fat weight vs. nonfat weight = body composition • Health and performance may be the best indicator © 2007 McGraw-Hill Higher Education. All rights reserved. • Lean tissue or lean body weight – Weight made up of bone, muscle, tendon, and connective tissue • Percent of body fat – The percent of the body weight made up of fat • Body composition is the relationship between fat tissue and lean body tissue Average Female 20-25% Should not be below 12% Male 12-15% 5% Healthy 5-18% 12-25% © 2007 McGraw-Hill Higher Education. All rights reserved. Assessing Body Composition or Percent Body Fat • Several methods – Hydrostatic or Under water weighing • Gold standard – Bioelectrical impedance • Measures electrical current going through body – Skinfold thickness measures • 3-5% error, must practice © 2007 McGraw-Hill Higher Education. All rights reserved. © 2007 McGraw-Hill Higher Education. All rights reserved. Assessing Caloric Balance • Caloric balance = Calories consumed - calories expended • Positive caloric balance results in weight gain • Negative caloric balance results in weight loss • Calories are lost or expended in 3 ways: – Basal metabolic rate (calories burned at rest) – Work/exercise (activities using more energy than sleep) – Excretion (losing some calories going to the bathroom) © 2007 McGraw-Hill Higher Education. All rights reserved. – – – – Carbohydrate = 4 calories/gram Protein = 4 calories /gram Fat = 9 calories/gram Alcohol = 7 calories/gram (macronutrient) (macronutrient) (macronutrient) (not a macronutrient) – Nutrition labels are based on 2000 calorie diet – College athletes consume 2000-5000 calories/day – Endurance athletes may consume as many as 7000 calories © 2007 McGraw-Hill Higher Education. All rights reserved. Methods of Weight Loss • exercise and good diet to lose weight • Only doing 1 is not long term solution • Dieting alone results in lean body tissue loss – Should not drop below 1000-1200 calories for women and 1200-1400 for men • Exercising will – Decrease fat mass – Increase muscular strength and endurance, cardiorespiratory endurance, and flexibility © 2007 McGraw-Hill Higher Education. All rights reserved. • The key is moderation – – – – A combination of dieting and exercise A negative energy balance must be achieved Lose no more than 1-2 pounds per week Weight loss of more than 2 pounds is dehydration or water loss • 1 pound = 3500 calories © 2007 McGraw-Hill Higher Education. All rights reserved. Methods of Weight Gain • Want to increase lean body mass (muscle) • Increased physical activity and diet • Approximately 2500 calories is required per pound of lean body mass, an increase 5001000 calories per day • A 1-2 pound per week gain is adequate © 2007 McGraw-Hill Higher Education. All rights reserved. Disordered Eating • Epidemic in our society, especially in sports • 1 out of 200 girls age 12-18 will develop some pattern of eating disorder (1-2% of population) • Bulimia Nervosa – Commonly females - ranging in age from adolescence to middle age – Periods of starvation, bingeing (thousands of calories) and purging through vomiting, fasting and laxatives/diuretics © 2007 McGraw-Hill Higher Education. All rights reserved. – Characteristics • Typically bulimic athletes are white, middle to upper-middle class • Perfectionist, obedient, overcompliant, highly motivated, successful academically, well-liked, and a good athlete • gymnastics, track, dance • occasionally seen in male gymnasts and wrestlers – Bingeing and purging can result in stomach rupture, heart rhythm, liver damage, tooth decay from acids, chronically inflamed mucous lining of mouth and throat © 2007 McGraw-Hill Higher Education. All rights reserved. • Anorexia Nervosa – 30-50% of anorexics also suffer from bulimia – Characterized by distorted body image and constant concern about weight gain – Impacts mostly females – Starts often with adolescents and can be life threatening – While the athlete tends to be too thin they continue to feel fat – Deny hunger and are hyperactive – Highly secretive © 2007 McGraw-Hill Higher Education. All rights reserved. • Early intervention is critical with eating disorders – Empathy is a must • Psychological counseling is key • Must have athlete recognize the problem, accept the benefits of assistance and must voluntarily accept help for treatment to work © 2007 McGraw-Hill Higher Education. All rights reserved. Female Athlete Triad • Potentially fatal problem involving a combination of disordered eating, amenorrhea, and osteoporosis • Incidence is uncertain – Eating disorders may be as high as 62% in some sports – Amenorrhea may be top out at least 60% • Major risk is the resultant loss of bone mass that can’t be regained © 2007 McGraw-Hill Higher Education. All rights reserved.