Sports Nutrition Unit 8.
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Transcript of Sports Nutrition Unit 8.
Sports Nutrition
Unit 8
Role of Diet if Athletics
Maximize their performanceProvide the necessary raw material to allow a good training program to build and run the human machineNutritional status, age, genetic background affect nutrient needsDiets must be individualizedMany myths and fads among athletes
Purpose of Nutrition
Good Nutrition promotes a healthier mind and bodyAids in resistance to illnessesEnergy and vitality are increasedHelp athlete feel better and sleep better
Functions of Food
The right combination of nutrients work together in the body to:
Provide heatPromote growthRepair tissueRegulate body processes
The United States Department of Agriculture (USDA)
Developed The Food Guide PyramidProvides the following basic dietary guidelines:
Eat a variety of foodsAvoid too much fat, especially unsaturated fat and cholesterolEat food with adequate starch and fiberMaintain a desirable body weightAvoid too much sodium and sugar
The Food Guide Pyramid
The categories in the pyramid are not considered to be equalsIdea is to get people to eat a more balanced diet. Benefits are many
Lower fatIncrease FiberGet more vitamins and minerals in dietProtect yourself from illness
Basic Nutrients
Chemical substances in food that:provide energyact as a building block in forming new body componentsAssist in the functioning of various body processes6 classes
Carbohydrates, Proteins, Fats, Vitamins, Minerals, and Water
CarbohydratesBasic source of energy for body heat and body activitiesSugars, starches, and fiber found in fruits, vegetables and grainsBody converts sugars and starches to glucose for energy or to glycogen for energy storage in the liver and musclesWhen glycogen stores are full, excess carbohydrates are stored to fatFiber is not absorbed but is essential for gastrointestinal functioning50-60% of caloric to keep glycogen stores filledCarbohydrate loading requires 70-80% carbohydrate intake
Proteins
Derived from animal foods-meat, milk, eggs, fish, cheese and poultryDerived also from soybeans, dry beans, some nuts and whole grain productsBroken down into 20 amino acids8 are essential to build and repair tissueBodies least efficient source of energyBody can not store protein, therefore extra is converted into fatIntake 10-12% of caloric intake
Fats (Lipids)
Fried foods, butter, margarine, salad dressings, oils, mayonnaise are all high sourcesMeats, eggs, milk and cheese contain fat tooProvide energy, carry vitamin A and D to cells, and are necessary for normal growth and developmentInsulate the body from temperature extremes Protect and shield body organ’s from impactAdd flavor to our food
Fats cont...
Are necessary, in fact important in dietOften eat far more than the daily recommended values30% of caloric intake is recommendedMost Americans consume 50% or more of their caloric intake from fatHigh fat diets are associated with heart disease, hypertension and cancers
Saturated or Unsaturated Fats
Saturated fats tend to raise the cholesterol level of bloodUnsaturated fats are subdivided
MonounsaturatedAre neutral effect on cholesterol
PolyunsaturatedLower 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 healthLack of vitamins lead to deficiency conditionsMost cannot be synthesized by body and must be ingested via foods or pillsNo single food or food group will supply all vitamins needed by the bodyEat a variety of foods
Fat Soluble or Water Soluble Vitamins
Fat SolubleVitamins A, D, E, and KEmulsified and absorbed in the small intestinesStored in body cells, especially the liver
Water SolubleB complex and Vitamin CAbsorbed along with water through the digestive track and dissolve in body fluidsBody does not store well, excess excreted in urine
Minerals
Inorganic substancesHave functions essential to life
CalciumNecessary for bone strength and muscle contractions
PotassiumRegulates cardiac rhythm
IronAssists hemoglobin in the delivery of oxygen to body tissues
SodiumEssential in maintaining fluid balance
PhosphorusNeeded for strong bones and teeth
Water
Necessities of lifeMost 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 bodyTwo phases
CatabolismReactions which break down complex organic compounds into simple compoundsProvides Energy
AnabolismSeries of reactions whereby small molecules are built into more complex molecules Form body’s structural and functional componentsRequires energy
Sports Nutritional Myths
Calories are caloriesFalse- 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 bodiesFalse-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 thirstyFalse- We need water long before we feel thirsty. Constant fluid replacement is required.
Body weight matters most; light athletes are fasterFalse- 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 hungerTo fuel your muscles with food eaten in advance that is stored as glycogen and food eaten within an hourTo pacify your mind with knowledge that your body is well fueled
Nutrition Benefits for Sport Performance
Eat adequate high carbohydrate mealsTo fuel and refuel your musclesFood 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 stomachFat delays gastric emptying and cause sluggishness and nausea
Be cautious with sugary foodsSoft drinks, jelly beans, sport drinks etc…Quickly enter the bloodstream as they are digestedIf 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 digestHigh calorie meals take longer to leave the stomach than do lighter snacksAllow 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 breakfastLearn how to best fuel your body
Nutrition Benefits Cont…
Always eat familiar foods before competitionDon’t try anything newNew foods always carry the risk of settling poorly, causing intestinal discomfort, acid stomach, heartburn or camps
Drink plenty of fluidsYou are unlikely to starve to death during an event, but you might dehydrateDrink an extra 4-8 glasses of fluid the day beforeDrink at least 2-3 glasses of water up to 2 hours beforeDink another 1-3 glasses 5-10 min before start
Pre-Event Training
TaperingIt is wise to gradually decrease the training program about 48 hours before competitionThis 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 athletesNO food, vitamin, hormone or supplement will substitute for sound nutrition and hard workVegetarian diet
Primary concern is whether enough protein is consumedProteins have essential amino acids and are balanced better in animal products than plant foodsMust 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 fuel1-3 pounds of water weight is usually gained during carbo-loading, since water is stored with glycogen70-80% 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 eventDaily 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 distressWhen you taper training, you do not need to intake additional calories, simply maintain standard intake
Carbohydrate LoadingInclude adequate protein
Especially endurance athletes who use some protein for energy
Do not fat overloadChoose wholesome, fiber-rich carbs
Keeps your system running smoothlyBran muffins, whole wheat bread, bran cereals, fruit
Plan meals carefullyDay before event, eat biggest meal at lunchtime so that the food has more time to digest
Drink extra fluids to hydrate your bodyAvoid alcoholic and caffeine beverages- dehydrating
Post Game Meals
What you eat after a hard workout or competition affects recoveryOften athletes do not feel hungry or don’t have time to eat after exerciseRecreational exerciser who works out 3-4 times a week, need not worry about recovery dietCompetitive athletes need to make careful selections of foods eaten after exercise
Football two a daysAn athlete with multiple event per meetTriathlete who trains twice a dayAn aerobic instructor who teaches several classes daily
Recovery Fluids
Loose fluids by sweat during exerciseBest replacements are by water, juices and watery foods like watermelonsDetermining how much you need to replace
Weigh yourself before and afterThe goal is to lose no more that 2% of bwAny more than 2% are you are dehydrated
Recovery Carbohydrates
Ideally you should consume carbohydrate rich food/beverages within 15 minutes after your workoutEnzymes responsible for making glycogen are most active at this time and will most rapidly replace the depleted glycogen storesLiquids and solids are equal
Recovery Carbohydrates
Popular carbohydrate rich foods are:8 oz or orange juice and medium bagel16 oz of cranberry juice8 oz fruit yogurtOne bowl of corn flakes with milk and bananaSport drinks
Be aware that they lack most vitamins and minerals that natural foods haveMore expensive
Recovery Protein
Protein can enhance glycogen replacement in the initial hours after hard exerciseProtein Eaten along with carbohydrates is a winning combination
Recovery Electrolytes
When you sweat you lose water as well as minerals such as potassium and sodiumElectrolytes are primarily responsible for muscle cramping and intolerance to heatYou 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 refuelingTo completely replace depleted glycogen stores, the muscles may need up to 2 days of rest with no exercise and a high carb dietExpect to experience soreness on the second day after strenuous exercise that damages your muscleQuality 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 itDrinking too little water or losing too much through sweating inhibits ability to exercise at maximum potentialFree 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 musclesIn blood, water carries away metabolic waste productsIn urine, water eliminates metabolic wasteIn sweat, water dissipates heat through the skin, regulating body temperatureIn saliva and gastric secretions, water helps digest foodWater helps to lubricate joints and cushion organs and tissues
Fluid Replacement
Plain water is most effective and inexpensive meansDrink 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 dehydratedThis 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 massWomen have approximately 10% more adipose tissue than do menFat is stored in various locations and severs as a protection and insulation to the bodyAverage Female 22-25% fatAverage Male 12-18% fatFat is a must, a goal of 0% is not possibleLess than 6% is unsafe for malesLess than 10% for women leads to amenorrhea
Measuring Body Fat
There are four common methodsUnderwater weighing, Skin calipers, BIA and NIR
There is no simple, inexpensive method to date that is 100% accurateStandard error of most measurement is plus or minus 3%Body Fat and Ideal Body Weight should be discussed togetherBody Fat changes as one
Lose fat, gain muscle, shape up or slim down
Underwater Weighing
Traditionally considered to be most accurateSubject exhales all the air in their lungs and is then weighed while submerged in a tank of waterMeasures body density and is translated mathematically into percent body fatErrors
Not completely exhaling all air out of lungsEquipment may not have precise weighing systems
Skin fold Calipers
Convenient and relatively accurateCalipers are large “pinchers” that measure the thickness of the fat layer of specific body sitesErrors
Poorly calibrated calipersImprecise location of the specific body sites
Bioelectrical Impedance Analysis
Computerized method with increasing accuracyCurrent current is sent through the body via electrodes attached to wrists and anklesFlow of the current is affected by the amounts of water in the bodyBecause water is the only fat free tissue, current flow can be translated into percent body fatErrors
If you are dehydrated, premenstrual, have undigested food in your stomach or are improperly positioned during the test
Near Infrared Reaction
Measures the thickness of the skin at only one siteMay poorly represent overall body fatBased on the principles of light absorption and reflectionAn instrument that emits an infrared light beam is placed over the bicepsThe light that is absorbed by the muscle and fat and is reflected off the boneThe measurement at only one site limits the accuracy
Weight Gain
Proper exercise and diet must be combined in right waysIn order to gain 1 pound of body weight per week you need to consume an additional 500 calories per day- above normal intakeExtra calories should primarily come from extra carbohydrates rather than extra proteinsProtein Powders and amino acid supplements are fruitless expenses
Weight Gain Challenges
Finding time to eat can be hard, here are some tips to help boost caloric intake
Pack portable snacksEat frequentlyEat an extra snackEat larger than normal portions at mealtimeEat higher calorie foods
You most likely to gain weight if you consistently eat larger than normal meals
Weight Gain Summary
Consume 500-1000 additional calories per dayInclude muscle-building exercise- weight workouts to promote muscle growth rather than fat depositsHave your body fat measured, to be sure that your weight gain is mostly muscle not fat
Weight Loss
High energy, low calorie reduce programs are the best possible method for weight loss Wisely choose what and when you eatBefore attempting a weight loss program have your body fat measured
Weight Loss Facts
To lose weight and successfully keep it off you should do the following:Pay attention to how much you eat
Calories do count! The amount of calories is important, not just the amount of fat grams
Pay attention to when you eatEat big breakfasts rather than big dinners
Pay attention to why you eatAre you bored, stressed, lonely, or actually hungry
Weight Loss Summary
Eat 500 fewer calories per day than you normally do You should only lose 1-2 pounds per week for a safety reasonsEat slowly- the brain needs 20 minutes to receive the signal that you are fullExercise regularly, but do not over exercise
Eating Disorder Statistics
One out of every 150 American girls ages12-30 develop patterns of an eating disorder (among athletes much higher)At least 1/3 of all Americans are obese and 60% are overweight77% of individuals with eating disorders report that the illness can last 1-15 yearsThe mortality rate for eating disorder is 20%Only 50% of all people with an eating disorders report being “cured”10% of all eating disorders are males
Eating Disorder Facts
All people with an eating disorder can die at any time and at any weight- not just extreme casesMost often death is due to a “side effect” such as cardiac arrest or kidney failureEating disorders are on the rise among active peopleSports that emphasize weight such as running, gymnastics, dancing, wrestling, and figure skating4 types of eating disorders:
Anorexia Nervosa, Bulimia NervosaCompulsive Eating and “Bigger-exia”
Eating Disorder Thinking Process
Food is not fuel, it is the “Enemy”Desire to be perfectly thinGoal is thinness at any priceDistorted body imageFeeling loss of control over their livesEating disorder sometimes is not about the food, but rather a way to exert some control over something in their lives
Signs to an Eating DisorderSocial isolationLack of confidenceRitualistic eating behaviorsObsession with calories and weightDistorted body imageWearing layers of baggy clothesNervous at mealtimePatterns of leaving table after mealtimeHyperactivity/compulsive exerciseDecrease in performance Recurrent overuse injuries
Running water in the bathroom after mealsSignificant weight lossObsession with gradesObsession with organization and personal spaceHigh emotionsSigns of MalnutritionMenstrual irregularitiesLoss of hairLight headednessBlood shot eyesInability to concentrateChronic fatigueDepression
Typical Victim
PerfectionistObedientOver compliantHighly motivatedSuccessful academicallyWell likedGood athlete
Anorexia Nervosa
Restriction of caloric intake for long period of time and deliberately starve themselvesLoss of body weight of at least 15%Achieved by avoiding food, frenzied exerciseIntense fear of becoming obeseDistorted body image
American Psychiatric Association
Defines anorexia Nervosa asIntense fear of gaining weight or becoming fat even though they are already under weightDisturbance in body weight perception- claiming they “feel fat” Weight loss to less than 85% of normal weightRefusal to maintain body weight over a minimal normal weight for age and heightDenial of the seriousness of the current weight lossAbsence of at least three consecutive menstrual cycles
Anorexia is a life threatening condition if left untreated
Bulimia Nervosa
A cycle pattern of binge-eating associated with some type of purgingPurging takes on different forms
FastingSelf-induced vomitingExcessive exercisingUse of enemas or diuretics
American Psychiatric Association
Defines Bulimia asRecurrent episodes of binge eating, characterized by both of the following:
Eating an unusually large amount of food in a discrete period of timeFeeling out of control during the eating episodes and unable to stop eating or control what and how much is eaten
Compensating for the binge to prevent weight gain such as induced vomiting, misusing laxatives, enemas, or other medications, fating or exercising excessivelyBinge eating and purging, on the average at least twice a week for three monthsEvaluation of self worth according to body shape and weight
Side Effects of Anorexia/Bulimia
Up to 50% of individuals who have been diagnosed with anorexia will also develop BulimiaEating disorders are extremely dangerous!Some serious medical complications are commonly seen in Anorexic and Bulimic individuals are:
Stomach ruptureTooth decayInflammation of the mucous lining of mouth and throatEventually cause heart, kidney and liver damageUrinary infectionsOsteoporosisMenstrual irregularities
Compulsive Eating
Largest percentage of individuals with eating disorders are compulsive eatersA compulsive eater keeps eating beyond the time when hunger has been satisfiedEating is driven by anxiety, feat, frustration, or anger rather than by hunger or pleasureFeel great amount of guilt and shame after eatingFeel envious and inferior toward others who handle food better than they doMay be a compulsive dieter as well
More about Compulsive Eating
You can be any weight and be a compulsive eaterA person can be heavy and obese and not be a compulsive eater
It is the relationship to the food that determines whether or not a person is a compulsive eaterA person who values food for its instant gratification and its ability to comfort, defuse anger, or help calm down is probably a compulsive eater
“Bigger-exia”New term to described individuals who use steroids and other ergogenic aids to build muscle massThey are both compulsive and excessive about body building workoutsSee extreme size not as an exaggeration but as something to aspire toFeels the need to be big and powerful in order to feel good about themselves
Reverse of people who desire to be thinA lot of health problems associated with use of some ergogenic aids
Treatment
Any victim must be approached and handled extremely carefully!Referral for medical treatment is essentialTrue anorexic and bulimic commonly deny the problem, insisting that they are perfectly fine
Eating Myths
Many athletes believe that by restricting food intake to lose weight that they will exercise better, look better and enhance performanceRestricting food actually; depletes fuel stores, cause ammenorrhea, stress fractures, fainting, weakness, fatigue and impaired performanceCan maintain for a while, but lack of energy and injuries will catch up with them
Prevention of Eating Disorders
People need to learn to love their bodiesAs a society we must:
Dispel the myth that thinness equals happiness and successDiscourage the notion that the thinnest or most muscular athlete is the best athleteLove our bodies for what they are, rather hate them for what they are notEmphasize fit and healthy as more appropriate goals than slender and skinny
Ergogenic Aids
Any substance (or food) that is believed to enhance one’s performance above normal standardsIOC definition: (summarized)
The administration or use of substances in any form alien to the body with the exclusion aim of attaining an artificial and unfair increase in performance in sports
Use of these substances and practices is controversial
Drug testing has been instituted in many sports in order to help curtail the use of these substances Because of the inequities that result in competition and health problems can result, the use of these substances cannot be condoned
Examples of Ergogenic Aid
Vitamins and mineralsAmino AcidsNutritional supplementsAnabolic steroidsCaffeineCreatine DiureticsHuman Growth HormoneOther illegal “recreational” drugs
Class 1 IOC Ergogenic Aids
StimulantsNarcoticsAnabolic SteroidsBeta BlockersDiuretics
Types of Stimulants
AmphetaminesCocaineEphedraCaffeine
Stimulants Effects
Increase alertnessReduce fatigueIncrease competitivenessProduce hostility
Increase blood pressureVomitingHeadachesIrregular heart beatAnxietyTremors
Caffeine Effects
Energy-enhancing effectMay reduce the fatigue associated with long bouts of exerciseHas a diuretic effectIn large quantities has been listed as a banned substance by the IOC
Narcotics
Morphine and codeine Used for management of moderate to severe painBanned by the IOCHigh risk for physical and psychological dependency
Beta Blocker
Produce a relaxation of blood vessels Slows the heart rate Decreases cardiac outputUsed in sports where physical activity is of little to no importance, but a steady hand is necessaryHeart rate and signs of nervousness are kept to a minimum
Diuretics
Increase kidney excretion and urine outputCan be misused in two ways:
To reduce body weight quicklyTo decrease a drug’s concentration in the urine to try to avoid the detection of drug misuse through urinalysis
Anabolic Steroid
Most commonly abused ergogenic aid in sportsIt is illegal to possess or distribute for non-medical usesSteroids are obtained on the black marketBanned by all sports governing boards including the IOC, NCAA and professional sport leagues
Anabolic Steroids
Synthetic forms of male sex hormonesIncrease muscle size and body weightGives athlete advantage over their opponentsNo studies that show steroids improve agility, skill, cardiovascular capacity or overall performanceMajor problem in sports that involve strength
Side Effects to using SteroidsIncrease muscle massPermanent side effects, including deathOther side effects to name a few
Aggression, mania and depressionHeart, liver and kidney disease/cancerRisk of HIV/ HepatitisAcne, Baldness, bad breath, decrease sex driveIncrease muscle, tendon injuriesInfertilityMale- increase risk to prostate cancer, growth of breasts Female-deep voice, facial and body hair, cervical cancer
Human Growth Hormone
Is naturally produced by pituitary glandCan be made synthetically and is readily availableIncreases muscle mass, skin thickness, body length and weight and decreases body fatMore difficult to detect in urine than steroidsPermanent side effects
Premature closure of growth sitesAcromegaly
Erythropoeitin / EPO
EPO is naturally produced by the kidneys as a response to a low oxygen levelCan be synthetically created and used as a supplementUsed generally by endurance athletesIncreases the number of red blood cellsSide effects
Stroke
Class II IOC Ergogenic Aid
Blood re-injection or “blood doping”Used by endurance athletes or events at high altitudePurpose is to increase blood volume and red blood cells to meet the increased aerobic demandsBanned my many sport governing bodies
Blood Doping
Blood is removed form the athlete and stored After at least 6 weeks the blood is re-infused into the athleteDuring the 6 weeks the body has reestablished a normal red blood cell countThe added blood raises the cell count to greater than normal levelsThis increases the oxygen carrying capacity and improves aerobic endurance
Risks to Blood Doping
Allergic reactionsClottingKidney damageFeverJaundiceTransmission of infectious diseaseShockHeart failure
Class III IOC Ergogenic Aid
AlcoholLocal anestheticsCorticosteroids
Alcohol
Number one abused substance in USActs as a depressantProduces sedation and tranquilityDoes not improve athletic performanceNot currently banned by IOC, however they can request a blood alcohol level and can take actions if the level is too high
Local Anesthetics and Corticosteroids
Inhibit or deaden the painSerious concerns:
The athlete will not feel the pain that could indicate a serious injuryContinued use of these drugs can lead to weakness and degeneration of tendons and ligaments
Prevention of Drug Use
Goal of sporting organizationsProtect the health of athletesHelp ensure that competition is fair and equitable
Sports programs should have full-service programs that provide substance abuse education, counseling and drug-detectionDrug testing should be done periodically in a random manner
Prevention of Drug Use
Athletes, parents, coaches, athletic trainers physicians and administrators must be educated about the dangers of drug abuse“Winning at all cost” is wrongPromote athletes to do their best and adhere to the rules
The End
Any Questions???