exam 2

What genetic factors affect REE?

•Age - Infancy through adulthood •Gender - Females REE about 10-15% lower •Muscle mass versus fat mass REE - infants have a large proportion of metabolically active tissue and are growing rapidly; extremely high REE REE declines through childhood, adolescence, and adulthood

How does body composition affect REE?

•Body composition -Muscle versus fat •Losing body weight lowers REE •Decline in REE with aging may be associated with loss of muscle mass Maintaining normal body weight while reducing

What environmental factors influence REE?

•Exposure to cold weather Thermogenesis - may stimulate heat production up to 400% •Exposure to warm or hot weather Increase energy expenditure due to sweating and cardiovascular demands •Exposure to altitude Increase REE due to increased ventilation •Cigarette smoking raises REE; nicotine stimulates metabolism •Caffeine One study reported caffeine in 2-3 cups of coffee increased REE 10-12% Most important factor that can increase the metabolic rate is exercise

Recovering from Extensive Exercise

•Refueling with carbohydrate and protein is beneficial in two ways: -CHO stimulates the release of insulin, hormone that helps build muscle and transport CHO into muscles to replenish depleted glycogen -CHO combined with a little protein (10-20 g) creates an even better response and reduces cortisol (hormone that breaks down muscle) •Consume 3x more CHO than protein •Right after exercise, muscle easily assimilate protein (amino acids) from the blood and use it to build muscle; muscles are also most efficient at absorbing CHO from the blood to replenish depleted glycogen stores •A little protein 10-20g •Cortisol, a hormone that breaks down muscle •Whip up a fruit smoothie with Greek yogurt, berries, and bananas or enjoy some chocolate milk! Or enjoy a meal such as chicken with brown rice

What energy sources are used during rest?

•The oxygen energy system prevails during rest -About 60% of energy is derived from fat -About 40% from carbohydrate -Small amount of energy from protein

Thirst 101

•Thirst usually controls water intake •Sensation of thirst triggered when body fluid concentrations are unusually high •Lose significant amounts of water from blood when you sweat •Remaining blood becomes more concentrated and has high sodium level which triggers your thirst mechanism and ↑desire to drink •To quench thirst, need to replace water losses and bring blood back to normal concentration

What should I eat before lifting weights?

•by eating a little protein with CHO in preexercise snack, you'll start to digest the protein into AA which gets used by the muscles during and after exercise; pre-ex protein can also reduce muscle breakdown that happened during exercise; whether this translate to bigger muscles has yet to be determined but certainly can't hurt

complex carbohydrates

- starch in plant foods - veggies - sweet when young, starchy when ripen - fruits - starchy when young, sweeter when ripen

CHO Needs

-3-5 g/lb (6-10 g/kg) for endurance athletes -Fitness exercisers need less CHO than endurance athletes -45-65% of daily calories -For a 125 lb person, 375-625 g CHO (1875-2500 kcal)

Carbs Rule

-CHO-based foods less fattening than fatty foods -Need CHO to fuel your muscles -Burn CHO during hard exercise -When dieting to lose weight, energize w/ fiber rich cereal, whole grains, potatoes, & CHO-dense veggies but lower intake of butter, margarine, mayo -For added satiety, enjoy minimally processed CHO in combination with protein such as oatmeal with nuts, banana with PB, ww pata with turkey meatballs

Quick and Slow CHO

-Glycemic index - based on how 50g (200 kcal) of CHO will affect blood sugar levels after an overnight fast -Low glycemic index foods -slow release of glucose into bloodstream -apples, yogurt, lentils, beans High glycemic index foods? -rapid spike in blood sugar -sports drink, jelly beans, bagel

RDA (Recommended Daily Allowance

amount per day that should decrease risk of chronic illness

Tips for Competitive Athletes

•Always eat familiar foods before competition •If you know you will be unable to tolerate any food before an event, eat well the day before •If you have a finicky stomach, experiment with liquid meal replacements •If traveling, pack tried-and-true foods •Drink extra fluid the day before

What are the three components of total daily energy expenditure?

•Basal and resting energy expenditure •Thermic effect of food •Thermic effect of exercise Basal metabolism Basal metabolic rate (BMR) Energy needed to stay alive when awake Only sleeping metabolic rate is lower Basal energy expenditure (BEE) Basal metabolism over 24-hour period Resting metabolism Resting metabolic rate (RMR) BMR plus small amounts associated with eating, prior activity About 10 percent higher than BMR

How reliable is the thirst mechanism?

•Can be an unreliable signal to drink •Can be blunted by exercise and overridden by the mind •Plan to drink before you are thirsty •By time brain signals thirst, may have lost 1% of body weight -Example: 150 lb person - 1% = 1.5 lbs (24 oz) •HR ↑ 3-5 bpm •2% loss = dehydration •3% loss can significantly impair aerobic performance •Drink enough to quench your thirst, perhaps a little more •What about children? Children have a poorly developed thirst mechanism •Older adults less sensitive to thirst mechanism •Stop if your stomach is sloshing •Remember, you will voluntarily replace only 2/3 of sweat losses

Replacing Sweat Losses

•Dissipate heat by sweating •As sweat evaporates, it cools the skin which cools the blood which then cools the inner body •If you didn't sweat, you would cook yourself to death

•Specific recommendations for recovery:

-0.5 g of carbohydrate (1g/kg) and 0.1 to 0.15 g of protein per pound (0.25 to 0.3 g/kg) -Example: •150 lb x 0.5 g CHO = 75 g CHO = 300 kcal carbohydrate (75 kcal x 4 kcal/g) •150 lb x 0.1-0.15 g protein = 15-22 g protein, more easily 20 g protein = 80 kcal protein •CHO-protein combinations that fit the formula above -3 scrambled eggs and a bowl of oatmeal with maple syrup -16 ounces chocolate milk and energy bar -Peanut butter and honey sandwich and yogurt -Turkey sub and grape juice -Fruit smoothie (1 cup sweetened Greek yogurt with banana and berries)

What is carbohydrate loading?

-A dietary technique designed to promote a significant increase in the glycogen content in both liver and muscles in an attempt to delay onset of fatigue -CHO content in common foods -If training for an enduarance event that lasts more than 90 minutes - marathon, triathlon, XC race, long distance bike race, you should start the race with muscles that are CHO loaded -Generally used 3-7 days in preparation for a major athletic competition

Protein and Amino Acids

-All proteins are made up of amino acids that body needs to build tissue - building blocks 20 AA -How many amino acids are there? 20 -How many are essential? 8 for adults and 9 for children; must come from the foods you eat -Examples of complete proteins ¤Rice + beans ¤Legumes + seeds - chickpeas and tahinia (as in hummus)

Glycogen Storage

-Average 150 lb man has about 1800 kcal stored CHO -Muscle glycogen - 1400 kcal -Liver glycogen - 320 kcal -Blood glucose - 80 kcal -CHO in muscle used during exercise -CHO in liver released into bloodstream -Cycling study

Fat storage

-Average lean 150 lb man has 60,000 -100,000 kcal of stored fat -Fat cannot be used exclusively as fuel because muscles need a certain amount of CHO to function well -CHO limiting factor for endurance athletes -During low-level ex such as walking, muscles burn primarily fat for energy -During to light to moderate aerobic exercise such as jogging, stored fat provides 50-60% of fuel -Sprinting - rely primarily on glycogen stores

How can you prevent hyponatremia?

-Avoid water loading before event --Eat salted foods and fluid 90 min before event Consume an endurance sports drink with higher sodium amounts during extended exercise in heat lasting > 4 hrs -Consume salty foods during endurance events as tolerated -Stop drinking water during exercise if stomach is sloshing Salted foods (soup, pretzels, salted oatmeal); dose of sodium results in fluid retention in body; extra fluid will help you exercise longer and make exercise seem easier Stop drinking water during exercise if stomach is sloshing as may happen when you drink more than a quart of water per hour for extended periods

Body Temperatures

-Body temp > 106⁰ F → damages cells -107.6 ⁰ F → cell protein coagulates and cell dies -For every lb lost during exercise, drink 80-100% of that loss (13-16 oz) -Dripping sweat less efficient @ cooling than evaporating sweat •Cell protein coagulates (as egg whites do when they cook) and the cell dies •This is one reason why you should push yourself beyond your limits in very hot weather

Beta-Hydroxy-Methylbutyrate

-By-product of essential AA leucine metabolism -Helps inhibit proteolysis •Shown promise in promoting muscle health •Leucine acts as a metabolic trigger to stimulate muscle growth •Helps prevent muscle wasting in chronically ill patients -In athletes, HMB may ↓ muscle protein breakdown and improve recovery Another muscle builder - HMB Leucine acts as a metabolic trigger to stimulate muscle growth Proteolysis - natural process of breaking down muscle that occurs especially after high intensity activity

Bone and Joint Protectors

-Chondroitin - may swear it helps them; given a very low risk of harm, users can continue to take it if they believe it helps the -Gives cartilage elasticity by helping it retain water -Review of 20 trials with 3486 patients with osteoarthritis of knee suggests that benefits of chondroitin is minimal or nonexistent -No evidence that chondroitin helps athletes prevent cartilage damage Glucosamine -Key component used in the maintenance and regeneration of healthy cartilage -Has not conclusively proven to prevent joint deterioration but glucosamine sulfate may help ease moderate to severe arthritis pain -Often taken in conjunction with chondroitin

Bonking

-Depleted liver glycogen causes bonking -Liver glycogen feeds into bloodstream to maintain normal blood sugar level essential for "brain food" -Symptoms? athlete may feel uncoordinated, light-headed, unable to concentrate, wekened because liver is releasing inadequate sugar into bloodstream; brain cannot store glucose or burn fat; for brain to function optimally, you must consume food close enough to strenuous events to supply suagr in bllod so brain has fuel Gianna -Athletes with low blood sugar tend to perform poorlybecause poorly fueld braain limits muscular function and menatldrive; grumpy, irritable

Fluid and Electrolyte Requirements

-Fluid needs vary -Sweat rates range from 1-4 lbs/hr -Factors affecting sweat rates? depend on sport, body size, intensity of exercise, clothing, weather, whether or not acclimatized, training status -How can you tell if you are replacing sweat loss? check the color and quantity of urine - urine may be dark if taking vit supplements so in that case, volume will be a better indicator than color In addition to monitoring urine and weight loss, also need to pay attn to how you feel - if you feel chronically fatigued, headachy, lethargic, may be chronically dehydrates

Fluids During Exercise

-Goal - prevent excessive dehydration , defined as a loss of more than 2% of body weight as a result of a water deficit -If exercising more than 3 hours, know your sweat rate -What should you drink during exercise? Fluid containing a little sodium, potassium, and CHO -If exercising > 1 hr, consume 120-240 kcals of CHO (30-60 g) per hour along with water >2.5 hours, consume 60-90g CHO/hour -Sports drinks Sodium - stim thirst Potassium - help replace sweat losses CHO - provide energy CHO helps maintain normal blood glucose levels to sustain energy Sports drinks convenient way to get CHO and water Gatorade - 16 oz 25 g CHO and 100 kcals

•8:00pm event such as a basketball game

-Hearty CHO-based breakfast and lunch; plenty of water -Plan for an early dinner as tolerated by 5:00pm and perhaps a pregame snack at 7:00pm -Drink extra fluids all day (pasta with tomato sauce and meatballs or chicken with a large serving of rice or a potato plus rolls, fruit salad, and frozen yogurt)

2:00pm event such as football or lacrosse game

-High CHO dinner and drink extra fluids day before and up to noon -Have a CHO-based breakfast such as French toast and a light lunch or a substantial brunch by 10:00am (French toast, pancakes, or cereal and poached eggs on toast) allowing 4 hours to digest

Too much protein can impair health and performance

-If you fill up your stomach with too much protein, you won't be fueling your muscles with CHO -Body can only use 20-25g of protein at any one time to build muscle (Phillips and van Loon, 2011) -High protein diet may high in saturated fat Anyone who eats extra protein should drink extra fluids You can save $ and the environemt by etaing smaller portions of beef, lamb and other forms of animal protein; use that money to buy more sources of plant protein (beans, lentils, tofu and more fruits, vegetables, grains, and poatoes Reduce protein to 1/3 plate and fill other 2/3 with potatoes, vegetables, and whole grain bread

Iron

-Iron - necessary component of Hg - Hg - protein that transports oxygen from lungs to working muscles -Iron deficient - fatigue easily upon exertion -Other symptoms? - dizziness, headaches, spoon-shaped fingernails and toe nails, cravings for locorice or ice -Iron intake is set high because only a small percentage is absorbed -Bests sources - animal products and fish; body absorbs far less iron from plant sources

Turning Food into Fuel

-Mouth: starches are partially digested by saliva in the mouth. the swallowed food goes down the esophagus into the stomach -Stomach: the chewed food is liquified w/ gastric juices & ground down into smaller particles. protein is broken into amino acids. the food gradually empties into the small intestine, where the nutrients become available to the body. water can empty from the stomach at the rate of abs 1 quart per hr; solid foods take longer. emptying time depends on caloric density small intestine: starches break into simple sugars. protein is further digested into amino acids & fat into fatty acids. these digestive products are then absorbed into the bloodstream and either used or transported to the liver. the indigestible waste products move into the large intestine -Large intestine: receives indigestible waste products, reabsorbs water and minerals, and excretes waste as feces -Liver: receives digested food components and stores extra glucose to be released into the bloodstream for future use

Zinc

-Part of more than 100 enzymes that helps body function properly -Functions ¤Zinc helps remove CO2 from muscles when you exercise ¤Helps healing process -Zinc from animal protein better absorbed than zinc from plant Vegetarian athletes @ risk of zinc-deficient diet because zinc from animals is absorbed better than zinc from plants -Athletes who sweat heavily and incur zinc losses should aim for target intake

Protein and the Vegetarian

-Plant-based diet tends to have more fiber, less saturated fat and cholesterol, and more phytochemicals -Replace meat with plant proteins -Dairy foods are a great way to add extra protein -Complete proteins - tofu, tempeh, edamame, soy milk, quinoa, buckwheat, chia seeds •Phytochemicals - active compounds that are health protective •Protein in soy foods such as tofu, tempeh, edamame, and soy milk are complete proteins; protein in rice, beans, pasta, lentils, nuts, fruits, vegetables, and other plant foods are incomplete because they have low levels of essential AA; therefore vegetarians must eat a variety of foods to get a variety of AA that combine with incomplete protein to make them complete

Ice Hockey Study

-Relies on muscular strength and power -Primary fuel? CHO -Muscle glycogen stores decline 38-88% -High carb versus low carb 55-65% CHO recommended

Fuel and Nourishment in CHO?

-Sugary soft drink - energy, but no vitamins or minerals -Polymer sports drinks - energy but no vit/min unless fortifies -Fruits, vegetables, grains - energy, vit, min, fiber, phytochem - fuel your body needs to function best

What is the difference between quick and slow protein?

-Whey - digested and quickly absorbed into bloodstream; rich source of BCAA which are directly taken up by the muscles instead of first being metabolized by the liver -Casein - slowly absorbed; supplies a longer-lasting and sustained source of AA •Whey (comes from 20% of the protein found in milk); fast acting and a good source of raw materials for protecting muscles from getting broken down during ex and for building muscles after ex Casein - slowly absorbed; supplies a longer-lasting and sustained source of AA; also important in the muscle-building process; bedtime casein can enhance the bioavailability of AA throughout the night •Milk offers both rapid and extended protein activity in the body; milk and powdered milk are good alternatives to expensive protein supplements; whey powders often lack CHO needed to refuel muscles •Casein - makes up the other 80% of milk protein

Clark's 9-Step CHO Loading Plan

1. CHO load daily -2.5-3.5 g CHO/lb (6-10 g/kg) 2. Taper your training 3. Eat enough protein -.5-.8 g/lb (1.2-1.7 g/kg) 4. Don't fat load -20-25% kcal from fat 5. Pay attention to fiber intake 6.Plan meal times carefully 7.Drink extra fluids 8.Be sensible about your selections - don't CHO load on fruit alone, diarrhea; white breads onley - constipation; don't eat unfailiar foods the night before 9.Eat breakfast on day of event - very important; prevent hunger and maintain normal blood sugar levels; choose familiar foods

Percentage contribution from aerobic and anaerobic energy sources during different time periods of maximal work

Aerobic energy system 29% of energy in 200-meter dash 84% of energy in 1500-meter run Spencer and Gastin

Alcohol and Athletes

Alcohol is a depressant Late-night drinking can wreck the next day's training session Alcohol is a poor source of CHO Alcohol is absorbed directly from the blood into the stomach Liver breaks down alcohol @ a fixed rate - 4 oz of wine or 1 can of beer/hr Kcals in alcohol are easily fattening If you drink, drink in moderation •Depressant - slows rxn time, impairs eye-hand coordination, accuracy and balance •Alcohol enters the bloodstream within 5 minutes of drinking it •One six pack of beer = 900 kcal or 4 slices of cheese pizza!

Potassium Sources

All whole foods; meats, milks, fruits, vegetables, grains, legumes -potato, yogurt, oj, banana, pineapple, raisins, beer, cranapple, gatorade, cola

Beta-alanine

Amino acid that helps take the burn and fatigue out of high-intensity exercise by buffering the acid that builds up in the muscles; may benefit athletes who do sustained high intensity exercise for 1-7 minutes (rowers, swimmers, and sprinters), athletes who do repeated bouts of high intensity workouts (interval training and weightlifting), athletes who do stop and start sports (soccer and ice hockey); and athletes who sprint at the end of endurance events (marathons and bike races)

Glutamine

Amino acid that is an important source of fuel for immune cells; involved in healing wounds, boosting the immune system, fighting infection, and decreasing illness; sources include beef, chicken, fish, beans, whey, and dairy

Echinacea

An herbal remedy that supposedly prevents or shortens the duration of colds

Predominant Energy Systems in Runners

Anaerobic power (ATP-PCr) 60-200 meters (6-20 seconds) Anaerobic endurance (anaerobic glycolysis; lactic acid) 400-800 meters (43-103 seconds) Aerobic power (aerobic glycolysis) 5,000-10,000 meters (12-26 minutes) Aerobic endurance (aerobic lipolysis) 42.2-100 kilometers (125-360 minutes) Aerobic glycolysis Oxidation of glycogen or glucose Aerobic lipolysis Oxidation of fatty acids Aerobic proteolysis (limited energy production) Oxidation of glucogenic or ketogenic amino acids

Vitamin C

Antioxidant which is abundant is fruits and vegetables; involved in boosting the immune response and reducing potential cellular damage caused by free radicals

Carbohydrate

Best endurance enhancer; consuming this before during and after exercise is also the best way to enhance immune function by reducing the stress response

The best way to prevent dehydration is to drink when you are thirsty (Fact or Fiction?)

FALSE The facts...During days of repeated hard exercise, the best way to determine whether you are DRINKING enough to replace seat losses and Maintain normal water balance is to weigh yourself nude each day in the morning, after emptyingbladder and bowels. Your weight should remain stable assuming: •You are not restricting kcal to lose fat •You have not eaten abnormally high amounts of sodium the night before such as a water-retaining Chinese dinner •You are not experiencing 2-4 lbs of premenstrual bloat

Fact or Fiction? Nutrition supplements are highly regulated to meet tight government standards

False •The facts: vitamin and herbal supplements abide by a set of government regulations different from those for prescription drugs and other meds •Government has very little control over their purity, potency, safety, or effectiveness, and the supplement industry can therefore hype their products with little need to prove their claims •High potency and all natural tend to be buzz words

Dietary Sources of Vitamin D

Fatty fish and fish oils, cow's milk and formula -salmon, portobello mushroom, tuna, shrimp, milk, OJ, soy milk, yogurt, cereal, egg

Vitamin b sources

Fortified cereals, cheese, eggs, milk, meat, cabbage

Chondroitin

Gives cartilage elasticity by helping it retain water; no evidence that this supplement helps prevent cartilage damage in athletes; given its low risk of harm, users can continue to take it if they believe it is effective

The Basics

Good taste - if you like the flavor, you'll drink more and be less likely to be dehydrated CHO - look for bev with 50-70kcal of CHO (13-18g CHO) per 8oz; too much CHO slows absorption; too little leaves you dragging; for long hard, intense exercise, CHO from a variety of sources (glucose, fructose, and sucrose) or dried fruit, energy bar, and Gummi bears is better absorbed and offers an energy advantage Sodium important for maintaining fluid balance, sodium stimulates thirst and enhances fluid retention

What is the most important factor determining which energy system is used during exercise?

Intensity Most exercise tasks use a blend of the three major human energy systems, but use of one system will predominate depending on exercise intensity

Creatine

Naturally occurring compound found in the muscles (meat); important source of fuel for sprints and bouts of high intensity exercise lasting 1-10 seconds; may help increase lean body mass and increase strength

Vitamin A

Part of an eye pigments that helps you see in the dark

Vitamin E

Plays an important role in maintaining immune function; can become a potentially performance-eroding pro-oxidant; if consumed, should be done in moderation with no more than 500 IU

Iron sources

Red meats, fish, poultry, shellfish, eggs, legumes, dried fruits

Nitrate

Supplement that may improve performance in events lasting about 4-30 minutes; helps regulate blood flow and oxygen consumption; beetroot juice is a source

Think Food First!

Vitamin C - oranges and other citrus fruits, strawberries, kiwi, broccoli, peppers, tomatoes, leafy greens Vitamin E - sunflower seeds, almonds, peanut butter, wheat germ, avocados Beta carotene - carrots, sweet potatoes, broccoli, tomatoes, kale, cant, apricots Selenium - seafood, lean meat, chicken, whole grains, low-fat dairy

Add-Ins with Questionable Value

Vitamins - vitamins in sports drinks are not incorporated quickly enough during exercise to be of any benefit Ginseng, guarana, & other herbs - no solid data to support any claimed benefit of these substances and the amount in bev are prob too small to make any difference Caffeine - caffeine might rnhance performance or cause side effects such as anxiety, jitters, and irritability Protein - may alter the taste (less desirable) and slow gastric emptying; research suggests that protein in a sports drink is unlikely to offer a performance benefit during exercise Potassium, calcium, magnesium, and other minerals- in most cases,the amount of of these minerals lost in sweat is too small to create problems; these minerals can be easily replenished with fruits, vegetables, and other wholesome foods

What happens if you do not consume enough carbs?

You hit the wall!!! Must consume carbs to replenish muscle glycogen storage Also must eat breakfast to replenish liver glycogen which fuels the brain

Greta Waitz

big lunch rather than huge dinner -Abstain from too much wine, beer, and alcoholic bev; plae yellow urine; drink 2-3 glasses of water 2 hrs before and another cup 5-10 min before event

DV (Daily Value)

compilation of DRIs used on food labels; intended to provide a perspective on overall dietary needs

If exercising > 60 min and will be unable to consume kcal during exercise, be sure to eat well day before;

eat pre-exercise snack with a little protein and fat such as a poached egg on toast, bagel with PB

Sources of dietary cholesterol

egg yolk, meat, fish and shell fish, poultry, dairy products

All CHO are digested into glucose and then burned for....

energy or stored for future use - muscle and liver glycogen

What happens when glycogen stores are full?

excess calories are stored as fat

Estimation of RMR

females 3-9 (22.5 x bw*) + 499 10-17 (12.2 x bw) + 746 18-29 (14.7 x bw) + 496 30-60 (8.7x bw) + 829 > 60 (10.5 x bw) + 596 ex: 10% of 1,304 = 130 calories normal range: 1,174-1,434 calories/day

Complete protein sources

foods that supply all the essential amino acids in adequate amounts Meat, fish, poultry, eggs, milk, cheese, and soy

incomplete protein sources

foods that supply most but not all essential amino acids Plants, including legumes, grains, and nuts

Vitamin C sources

fruits and vegetables

DRI (Dietary Reference Intake)

recommendations for vitamins and minerals exceed the average nutrition requirements for nearly all people including athletes

Zinc food sources

red meats, poultry, shellfish, whole grains

During hard exercise, your muscles can generate 20x more heat than when you are at

rest

Taper training

some scientists suggest reducing exercise time to 30% of normal 7-10 days before eveny; short intense speed intervals to keep you sharp

Disaccharidases

sucrose, lactose, corn syrup, honey

Vitamin D sources

sunlight, egg yolk, fortified milk

Sodium Sources

table salt, processed foods -chicken noodle soup, Mac&cheese, ramen noodles, pizza, pretzels, bread, cheerios, coke, beer, potato chips

Iron ..

transports oxygen to the muscles

True or false? CHO-rich grains, fruits, and vegetables are the best foundation for any type of training program.

true •Even body builders need a cho-based diet because cho is stored in the muscles for energy; you can't lift weights and demand a lot from your workout if your muscle are CHO depleted; protein-based diets low in CHO provide inadequate muscle fuel for you to perform the hard exercise required to build to your potential •Best sports diet contains ample but not excessive protein to build and repair muscle tissue, grow hair, and fingernails, produce hormones, boost your immune system, and replace rbcs

AI (Adequate Intake)

used when an RDA cannot be determined for a particular nutrient

Homemade sports drink

water, orange juice, sugar, salt, lemon juice -can use any 100% juice CHO, sugar, sodium

What happens when glycogen stores are too low?

we have this overwhelming feeling to hit the wall, overwhelming fatigue, desire to quid

Dietary Protein

¨Best sports diet contains ample, not excessive protein ¨Most people who eat moderate portions of protein-rich foods get more protein than they need ¨Any excess protein is burned for energy or stored as fat or glycogen ¨Humans do not store excess protein as muscle, protein, or amino acids (acids so we must consume adequate protein every day, evenly distributed throughout the day; particularly important for dieters restricting kcal because they burn protein from food and muscles for energy when CHO and calories are scarce) ¨Functions Build and repair muscle tissue Grow hair and fingernails Produce hormones Boost your immune system Replace red blood cells

Protein Powders, Shakes, and Bars

¨Extra kcal and exercise, not supplements, add bulk ¨Protein or amino acids in supplements are no more effective than protein in ordinary foods ¨Exercise, not extra protein, is the key ¨Be aware of extra fat ¨Expensive muscle-building supplements are not the answer

Defining Protein Needs

¨Individual protein needs vary ¨Following groups have the highest protein needs ¤Endurance athletes and others doing intense exercise ¤Dieters consuming too few kcals ¤Growing teenage athletes ¤Untrained people starting an exercise program ¤People over 50 years old ¨Athletes need slightly more protein to repair small amounts of muscle damage, provide energy in small amounts, & support the building of new muscle •Endurance athletes and others doing intense exercise; about 5% of energy can come from protein during endurance exercise, particularly if MG stores are depleted and blood glucose is low •Dieters consuming too few kcals - when kcal intake is low, protein is converted into glucose and burned for energy instead of being used to build and repair muscles •Growing teenage athletes - protein is essnetial for both growth and muscle development •Untrained people starting an exercise program - people in this category need extra protein to build muscles

Nutrient Timing

¨Pay attention to when you eat protein ¨Consume high-quality protein in close proximity to exercise followed by protein-rich meals and snacks evenly distributed throughout the day ¨When AA levels in the blood are above normal, muscles take up more of these building blocks and enhance muscle growth ¨Eating several protein-rich meals and snacks is preferable to eating one big meal

Eating the Right Foods...

•10:00am event such as a bike race or soccer game -Eat high CHO-based dinner and drink extra water day before -Eat a familiar breakfast by 7:00am (oatmeal, bagel with peanut butter, and yogurt with Grape-Nuts and berries) •11:00am lightweight crew match, wrestling, or other weight-class sport -Replace water, CHO, and sodium -Chicken noodle soup, bread, lots of water -Salted boiled potatoes, broth, salted crackers, and water -Ginger ale or cola, a ham sandwich with mustard, and water CHO-based dinner such as chicken stirfry with extra rice Eat breakfast three hours before to allow for food to digest; this meal will prevent fatigue that results from low blood sugar 11:00am - or other weight classs sports that requires a weigh in 1-2 hours prior to event -Athletes that have crash dieted and dhydrated themselves have only a few hours after the weigh in to prepare for competition ; ideal target for a 150 lb depleted athlete would be 700kcal primarily from CHO, 220mg of sodium, and 2 quarts of water; intake will vary greatly depending on athletes tolerance for food

What should I eat to prepare for an all day event such as a hike, 100 mile bike ride, or day of XC skiing?

•2 days before, cut down on exercise •Rest day before to allow your muscles to replace depleted glycogen •Eat CHO-rich meals for breakfast, lunch, & dinner •Drink extra fluids •On day of event, eat tried-and- true breakfast depending on tolerance (oatmeal and bagels with peanut butter) •During event, eat CHO-based foods such as energy bars, dried fruit, sports drinks, gels every 60-90 min •Drink fluids before you are thirsty -you should need to urinate at least three time throughout the day

Eating the Right Foods at the Right Time

•8:00am event such as a road race, swim meet, or spin class -Eat CHO-rich dinner and drink extra water day before -6:00-6:30am - consume light 200-400 kcal meal such as yogurt and a banana or 1 or 2 energy bars -If want a larger meal, consider eating between 5:00 and 6:00am -For workouts less than 60-90 min, preexercise snack should be predominantly CHO because it empties quickly from the stomach (compared to protein and fat) and becomes readily available to be used by the muscles -But before extended exercise like a long run or a bike ride, adding PB to that bagel will contribute sustained energy

How is energy stored in the body?

•Adenosinetriphosphate (ATP) •Phosphocreatine (PCr) •Carbohydrate •Fat •Protein

Which energy source represents the greatest storage of potential energy in the form of total calories?

•Adipose tissue triglycerides

What should I eat after lifting weights?

•After a hard gym workout, your muscles are primed for getting broken down; their glycogen stores are reduced, levels of cortisol and other hormones that break down muscle are high; the muscle damage that occurred during exrercise causes inflmmation and the AA glutamine that provides fuel for the immune system is diminished; if you just guzzle some water after you workout, you will miss the 45 min post-ex windoe of opportunity to optimally nourish, repair, and build muscles; eat a CHO-protein combo as soon as tolerable to switch out of muscle breakdown mode; populat recovery choice include choc milk, fruit smoothies, fruit yogurt, all or half of a PB and jelly sandwich with a glass of milk

Endurance Enhancers

•Best endurance enhancer - CHO - foundation of any sports diet; consume before, during, and after exercise •Nitrate - can improve performance in events lasting 4-30 min Sources of dietary nitrite include: rhubarb, arugula, and beets; dietary nitrate stimulates production of nitric oxide; nitric oxide regulates blood flow and O2 consumption; for the same amount of O2 uptake, athletes with higher levels of nitric oxide can work harder; athletes see about a 1.5% improvement in performance; typical protocol is to consume 2.5 ounces of concentrated beetroot juice shots, 7 oz of baked beets or 200-500ml of beetroot juice, or other nitrite-rich sources equivalent to about 300mg of nitrite 2-3 hours before event; that's when nitrite peaks; remains elevated for another6-9 hrs before declining toward baseline; key is to experiment during training to be sure GI tract can handle this unusual prevent food •Beta-alanine - another endurance and performance enhancer, is an AA that helps take the burn and fatigue out of high intensity exercise by buffering the acid that build up in muscles; emerging evidence supports the benefits of beta-alanine supplements in athletes such as rower, swimmers, and sprinters who do sustained high-intensity exercise for 1-7 min; athletes who do repeated bouts of high intensity workouts such as interval training and weight training; athletes who do start and stop sports such as soccer and ice hockey; and athletes who sprint at the end of endurance events such as marathon runners and bike racers •Sodium bicarbonate - is known to buffer the lactic acid that accumulates in the blood and can improve performance in high intensity exercise that lasts 60 to 180 seconds; athletes who take sodium bicarbonate before performing high intensity interval training 3x week tend to have greater improvements in endurance performance; preferred way to take it in in capsules from the pharmacy; this contributes to less nausea and diarrhea compared to consuming baking soda; may cause GI distress •Caffeine - increases alertness, decreases reaction time, and makes effort seem easier; many athletes enjoy a caffeine boost before, during, or after exercise; increase time to exhaustion in aerobic endurance exercise bouts and decrease RPE during submax aerobic endurance exercise; caffeine also has the potential to decrease muscle soreness and augment glycogen resynthesis

Popular Immunity Boosters

•Carbohydrate - consuming CHO before, during, and after exercise is the best way to enhance immune function; being adequately fueled with CHO reduces the stress response •Echinacea - an herbal remedy, supposedly prevents or shortens the duration of colds; in a study of 437 people who were exposed to the common cold virus, taking echinacea before or after exposure did not affect the rates of infection or severity of symptoms •Glutamine - AA that is an important source of fuel for immune cells; involved in wound healing, boosting immune system, fighting infection, and decreasing illness; during physical stress (cancer or surgery), glutamine levels drop; glutamine supplements have been used with success in very sick PT with HIV/AIDs and cancer but research regarding the use of glutamine supplements can benefit healthy athletes when they are training intensely has been weak and inconclusive; most protein-rich foods are rich in glutamine - beef, chicken, fish, beans, whey, and dairy •Vitamin C - antioxidant that is involved in boosting the immune response and reducing potential cellular damage caused by free radicals; overtraining nad taking part in prolonged exercise can lower your immune response but taking high doses of vitamin C is unlikely to enhance your immune response; if you insist on taking vitamin C, 500mg is more than enough •Vitamin E - in low doses, vitamin E plays an important role in maintaining immune function; too much vitamin E can become a potentially performance-eroding pro-oxidant; can result in unexpected inflammation when taken in high doses; bottom line: if you chose to take vitamin E, do so in moderation; 500 IU is more than enough

Deciding whether to supplement?

•Choose a supplement with the vitamins and minerals close to 100% of DV •Don't expect to find 100% of the DV for calcium and magnesium listed on the label •Don't buy supplements that contain excessive doses of vitamins and minerals, especially minerals •Buy and use supplement before its expiration date •Look for USP on label •Choose nationally known brands •Take supplement with or after meal Don't expect to find 100% of DV for calcium and mg listed on label; these minerals are too bulky to put in one pill Store in a cool, dry place Natural vitamins - tend to be blends of natural and synthetic vitamins and offer no benefits; vit E more potent in natural form but diff is inconsequential USP - indicates manufacturer followed standards established by the U.S. Pharmacopia Nationally known brands may improve likelihood that you are getting what you believe you are buying Take supplement with or after meal to optimize absorption No supplement will compensate for a lousy diet

Dehydration and Performance

•Dehydration stresses the body -Body temperature ↑ -Heart rate ↑ -Burn more glycogen -Trouble concentrating -Exercise feels harder •2% loss - lose mental edge and physical ability to perform well, (especially in hot weather; yet in cold weather, you are less likely to experience reduced performance even @ 3%; that is, a runner feels less impact of dehydration on her performance during cold weather than she does during the same run in the summer heat.) •3-5% does not appear to affect muscle strength or short intense bursts of anaerobic performance •Sweat losses of 9-12% can lead to death •What are some warning signs of heat illness? - muscle cramps, nausea, vomiting, headache, confusion, disorientation, weakness, reduced performance, inability to concentrate, irrational behavior •More dehydrated you are, grain the strain you will experience •Athletes who train hard day after day can become chronically dehydrated if they fail to rehydrate daily

Fueling During Extensive Exercise

•During exercise lasting > 60 min, balance sweat losses and energy output with enough fluids and CHO to keep energy high and blood sugar at normal levels •High intensity exercise - stick with gels and sports drinks •Lower-intensity - use standard foods while working out •Sports drinks, sport beans, and gels offer similar performance benefits (Campbell et al. 2007) •Best bet - mix up your foods and fluids •Experiment during training •Determine your target fluid intake •Estimate your calorie targets •Be sure to drink enough water with gels •Table 10.1 shows several plans for fueling •Body doesn't care whether you ingest solid or liquid CHO, both are equally effective Because different sugars use different transporters,yucan absorb more CHO and have more fuel to support your endurance exercise if you choose a variety of foods that offer a variety of forms of CHO

Fueling During Tournaments and Back-to-Back Events

•Fruit - dried fruits such as dried cherries, pineapple, mango; applesauce; canned fruit, bananas, oranges, dates •Protein- almonds or any nuts, peanut butter, tuna, hummus, jerky, hard boiled eggs, cheese sticks, cheddar cheese, yogurt •Grains - granola bars, oatmeal squares or other dry cereal, pretzels, pita chips •Snacks and treats - energy bars, animal crackers, oatmeal raisin cookies •Fluids

Fluids Before Exercise

•Goal - start exercising when body is in water balance, not in deficit from previous exercise sessioN •Prehydration goal - drink 2-3 ml/lb (5-7 ml/kg) @ least 4 hr before exercise -150 lb person 300-450 ml (10-15 oz) fluid •Drinking beverage with sodium or eating a few salty snacks will stimulate thirst and help retain fluid •Be careful not to overhydrate •Body can absorb just so much fluid •By hydrating several hours preexercise, you have time to eliminate the excess before starting the exercise event •Body can absorb just so much fluid and you'll end up having to urinate during the event •1 oz = 30 ml

Preexercise Caffeine

•Helps athletes train harder and longer when taken in moderate amounts •Caffeine stimulates the brain, contributes to mental alertness, and greater concentration •Studies conclude that caffeine taken an hour before exercise enhances performance (by about 11%) and makes effort seem easier (by about 6%) Target dose is about 1.5-3 mg/lb(3-6 mg/kg 150 pund athlete -225-450 mg of caffeine

5 Main Functions of Preexercise Fuel

•Helps prevent hypoglycemia which can impair performance (with its symptoms of light-headedness, needless fatigue, blurred vision, indeciseness) •Settles your stomach, absorb some gastric juices, and ward off hunger •Fuels your muscles and feeds your brain - both with food eaten in advance that is stored as glycogen and with food eaten withon an hour •Gives you peace of mind knowing that your body is well fueled •Helps you exercise harder so you can burn more kcal if you prime motivation for exercsie is to lose weight

Cramping your style?

•Lack of water •Lack of sodium •Lack of calcium - to rule out any possible link between a calcium-poor diet and muscle cramps, athletes who experience cramps should consume dairy products or other calcium sources at least 2x/day •Lack of magnesium - just as muscles need calcium to contract, they also need Mg to relax; mg helps to relieve leg cramps that occur in the middle of the night; sources include green leafy vegetables, whole grains, nuts, beans, and legumes •Lack of potassium -may play a role in muscle cramps; bananas, oranges on a daily basis •People who are predisposed to cramping should rule out these possible contributing causes •Cramps commonly coincide with dehydration; t prevent dehydration-induced cramps, drink enough fluids befoe, during, and after exercise; always drink enough fluids so urine is pale yellow, clear, and copius •Athletes who exercose hard for more than 4 hours in the heat such as tennis players, triathetes, ultrarunnes may be putting themselves at risk for sodium imbalance that could contribute to camps if they consume only water during the event and no beverages that contain sodium; sports drinks and salted pretzels wise snack choices

•Best refueling occurs within an hour post exercise

•Low glycemic - yogurt, bananas, oatmeal, bean soup, lentils, apples; when eaten an hour before ex, these foods will be digested enough to be burned for fuel and will continue to provide sustained energy during the long workout •Snack on bread, English muffins, bagels, crackers •High fat proteins take longer to empty from the stomach because fat delays gastric emptying; small servings of low-fat protein can settle well and keep you from feeling hungry •Adequate time - high calorie meals take longer to leave the stomach than do lighter snacks; general rule of thumb - allow at least 3-4 hours for a large meal, 2-3 hrs for a smaller meal, 1-2 hours for a blended or liquid meal, and less than an hour for a small snack according to tolerance

Fueling Before a Workout

•Most athletes prefer to allow a full meal 3-4 hours to digest before exercising •Amount of food tolerated varies Cyclists often eat more than runners Cycling study - p. 188-189 For a 150 lb athlete who will be starting a 50-mile bike ride at 10:00am, 600 kcal at 8:00am would translate to: •A bowl of granola with a large banana and milk •Three or four pancakes with maple syrup •3 packets of oatmeal with a snack box of raisins

What are some tips for boosting your iron intake?

•Multivitamin and mineral pill with iron •If you eat meat, consume lean cuts of beef, lamb, pork, and dark skinless turkey or chicken 3-4x/week •Select breads and cereals that are "enriched" or "fortified" on label •Eat with vit C to enhance iron absorption •Use cast iron skillets •Don't drink coffee or eat with every meal esp. if prone to being anemic; drinking them an hour before is better than drinking them afterwards •Combine poorly absorbed veg sources of iron (non-heme; 10% absorption rate) with animal sources (heme; 40% absorption rate) if you eat meat

Electrolyte Loss in Sweat

•Muscle cramps can sometimes be associated with dehydration, electrolyte imbalances, and muscle fatigue •If you sweat profuselt, are lefted caked with salt, and experience cramps, make sure to drink plety of sodium-containing fluids before and during exercise; consuming extra salt in your food if you have sweated heavily is a smart way to enhance recovery, retain fluid, and stimulate thirst Sweat similar to (and derived from) plasma Mostly Na+, Cl- (concentrations will vary) Remaining ions in body must redistribute

Muscle Builders - Creatine

•Naturally occurring compound found in muscles •Important source of fuel for sprints and bouts of high-intensity exercise lasting up to 10 seconds •May also benefit endurance athletes who do high-intensity training - weight lifting, interval or sprint training with short bouts of explosive efforts, and team or racquet sports such as soccer, football, basketball, tennis, and squash •May help rebuild muscle after cast removal •Many athletes who take creatine report increases in lean body mass •Study of 31 experienced body builders who took a protein-CHO supplement w/ or w/o creatine @ mid-morning, after afternoon workout, and before bed (for a total of 450 kcal) suggests the creatine group gained more muscle mass and strength than those who consumed just protein and CHO (Cribb et al 2007) •Not all athletes experience enhanced performance with creatine -Response rate is variable 20-30% of athletes fail to see any changes in performan In a study with 21 subjects, 4 classified as nonresponders -Only fully developed athletes should take creatine Best muscle builder is resistance exercise that fatigues your muscles; hard work lays the foundation for building muscle mass To build muscle, you need to lift weights Creatine - typical diet of meat eaters contains about 2g creatine/day; vegetarians have lower body stores of creatine; many athletes that take creatine report increases in LBM because they are better able to recover during strength training; in research studies, subjects commonly take 3 g/day or they consume 20 g of creatine in loading phase for 3-5 days, then consume 3 g/day; creatine holds onto water so loading the body w/ creatine results in water weight gain; may not be ideal for weight conscious athletes such as sprinters; many health prof agree that only fully developed athletes should take creatine; young athletes need to learn to improve performance by training hard and developing sports skills; unlikely to cause med problems but may influence mental desire to look for short cuts to success

Hyponatremia

•Occurs when blood sodium levels become abnormally low •Hyponatremia that occurs in events lasting < 4 hrs caused by overdrinking water before, during, and after event •> 4 hrs due to extreme sodium losses •During exercise and heat stress, kidneys make less urine •Choose endurance sports drinks, salty snacks, salt tablets (250-500 mg sodium/hr) •More trained in heat, lose less sodium •No need to superhydrate before you exercise; your body can only absorb so much fluid •Kidneys regulate water balance by adjusting urine output from a minimum of a tablespoon to a maximum of a quart per hour; if you overdrink, you may need to urinate during exercsie; a wise trick is to drink 23 hours before exercise to allow time for your kidneys to process and eliminate the excess; then drink 5-15 min preexercsie •Drinking too much water can be lethal if it dilutes body fluids and creates a sodium imbalance During exercise and heat stress, kidneys make less urine; therefore, if athletes overhydrate during exercise, bodies may not be able to make enough urine to excrete excess volume; water dilutes electrolyte balance 4 hrs due to extreme sodium losses - slow marathon runners, triathletes, ultrarunners, and unfit weekend warriors who have high sweat losses than their ft counterparst Gatorade 20-40 ounces contains 250-500 mg sodium Training in heat, body losses less sodium and learns how to conserve sodium and other electrolytes

Supplementing in Special Situations

•Restricting kcals - dieters consuming < 1200 kcals may miss some important nutrients •Allergic to certain foods - fruits or wheat need to compensate with alternative vitamin sources to avoid deficiencies •Lactose intolerant - inability to digest milk sugar; avoiding dairy foods can result in deficiency of vit D, riboflavin, and calcium •Indoor athlete - may be short on the sunshine vitamin (vit D); calcium pill with vit D plus 15 min of reg activity in the sunshine without sunscreen •Traveling athlete - if you will be spending extended periods of time in countries with limited food supplies or will be doing extensive travel that is likely to dismantle your healthy eating program, you might want to take a multivitamin along for nutritional insurance •Contemplating pregnancy - eat a diet rich in folic acid and take a multivitamin with 400 µg of folacin •Pregnant - expectant mothers require additional vitamins and iron but should check with doctor before taking a supplement •Vegan - may be deficient in B12, vit D, and riboflavin; those who eat a poorly balanced veg diet may be deficient in protein, iron, and zinc •Elderly - poor nutrition is common among frail, elderly people who eat few kcal; fewer the kcal, higher the risk of vit and min deficiencies -Pregnant Should consider taking a multivitamin and mineral pill if you fall into any of the following categories: Taking a multivitamin and mineral pill can be a good idea for certain individuals who are @ risk for developing nutritional deficiencies

What are some predisposing factors for GI problems?

•Type of sport - cyclists, swimmers, xc skiers, any other who exercise in a relatively stable position report fewer GI problems than do runners or athletes in running-type sports that jostle the intestines •Training status - untrained people report more GI problems than do well-trained athletes •Age - GI problems occur more frequently in younger athletes •Gender - women report more GI problems, particularly at the time of menstrual period; hormonal shifts during menstruation can contribute to looser stools •Emotional and mental stress - athletes who are tense are more likely to report that food lingers longer in the stomach and settles like a lead balloon •Exercise intensity - during intense exercise, the shift of blood flow from the stomach t working muscles may be responsible for GI complaints •Precompetition food intake - eating too much high protein and high fat food shortly before ex can cause GI problems •Food taken during exercise - small amounts of familiar food usually O •Fiber - high fiber diets intesify GI complaints •Caffeine - diarrhea •Gels and concentrated sugar solutions - gels consumed during exercise may cause stomach distress •Level of hydration - dehydration enhances the risk of GI problems •Hormonal changes •Irritable bowel syndrome - estimated 10-20% of Americans suffer from IBS •Undiagnosed celiac disease

Vitamin and Mineral Supplements

•Vitamins - metabolic catalysts that regulate biochemical reactions within the body •Found in plants you eat and are created by plants •Minerals - natural substances that plants must absorb from the soil •Vitamins and minerals must be obtained in diet •How many vitamins and minerals have been discovered? 14 vitamins and 15 minerals each with a specific function •Body cannot manufacture vitamins and minerals - must be obtained in diet •You can get the recommended amount of most nutrients (except possibly iron) by eating 1500 calories of a variety of foods Although we do need vitamins and minerals to function optimally, no scientific evidence to date proves that extra vitamins and minerals offer a competitive advantage By eating a variety of wholesome foods, you can consume to right balance of vitamins and minerals

Muscle Glycogen Storage

-Biochemical changes during training influence amount of glycogen stored in muscles -Well-trained muscles store 20-50% more glycogen than untrained muscles -Muscle glycogen stores per 100 g (3.5 oz) of muscle -untrained muscle - 13 g -trained muscle - 32g -CHO-loaded muscle 35-40 g

Which athletes are @ greatest risk for developing iron-deficiency anemia?

-Female athletes who lose iron thru menstrual bleeding -Vegetarians who do not eat red meat -Marathon runners who may damage RBCs by pounding their feet on the ground during training -Endurance athletes who may lose iron through heavy sweat losses -Teenage athletes, particularly girls, who are growing quickly and may consume inadequate iron to meet expanded requirements

Calculating Protein Needs

-What are the protein needs for a 140 lb bike racer? -140 x .6g/lb = 84 g protein -140 x .7g/lb = 98 g protein -Protein in common foods - Table 7.2 on p. 144-145 Endurance athlete, adult

Protein Recommendations

10-35% kcals

Major energy stores in the human body

ATP, Per, CHO, fat, protein

Calories in Food

Kcals in 8 oz of OJ provides enough energy for the average male to run a mile 112 calories

Glucosamine

Key component used in the maintenance and regeneration of healthy cartilage in joints; may help ease moderate to severe arthritis pain

Sodium Bicarbonate

Known to buffer lactic acid that accumulates in the blood; can improve performance in high-intensity exercise that lasts for 60-180 seconds; athletes who take this supplement before performing high-intensity interval training 3x/week tend to have greater improvements in endurance performance

Sources of Fuel

Low level exercise - fat primary source of fuel Light to moderate - stored fat provides 50-60% of fuel Hard - rely primarily on glycogen stores

What to Look for in a Sports Beverage

The Basics -Good taste -CHO -Sodium -Add-Ins with Questionable Value Vitamins -Ginseng, guarana, & other herbs -Caffeine -Protein -Potassium, calcium, magnesium, and other minerals •What you may not want... •Carbonation - bubbles can make you bloated and fill up sooner •Plastic bottles - litter the environment if not recycled and are a potentially a source of hormone-disrupting BPA; consider having just one BA-free bottle (stainless steel or aluminum) that you refill daily

Vitamin D

controls the way your body uses calcium

Gluten free CHO loading

rice, corn, yams, chickpeas, bananas, vegetables, juices but not wheat, rye, barley, and sometimes oats Body cannot tolerate gluten (celiac disease)

If exercising < 1 hr

snack on foods that digest easily and settle comfortably such as toast, banana, crackers, granola bar

Female Athletes and Amenorrhea

¨Some athletic women consume a very low calories and low protein vegetarian diet ¨Amenorrhea - 2-4x greater risk of stress fracture (ACSM 2007; Nattiv, 2000) ¨Eating a well-balanced diet can enhance resumption of menses, provide adequate protein for building and protecting muscles, and enhance overall health Drastic restriction of food intake can lead to ammenorrhea 2-4x greater risk of stress fracture compared to regularly menstruating athlete Eating a well Plant protein is less concentrated than animal protein so you must eat larger portions to get the same amt of protein

Refueling After Exercise

•#1 priority - replenish fluids •#2 priority - optimize muscle glycogen replenishment by consuming CHO-rich foods and beverages and a little protein to enhance recovery Goal - drink on schedule and lose no more than 2% of body weight (3 lbs for 150 lb person)

What is the immediate source of energy for metabolic activity including muscle contraction?

•ATP!!! •PCr can regenerate ATP rapidly •Both ATP and PCr are in very short supply •Carbohydrate, fat and protein can be metabolized to produce ATP and PCr

Suggestions for traveling athletes:

•Dry ceral (oat squares, Cheerios, granola) •Crackers, hard pretzels •Dried fruit, trail mix, nuts •PB, jam, honey •Tuna pouches •Water, juice, sports drink, chocolate milk boxes

What effect does eating a meal have on the metabolic rate?

•Metabolic rate is elevated after a meal -Thermic effect of food (TEF) TEF is expressed as the % of meal energy content 5-10% for a mixed meal TEF may be a consideration in some weight-control diets

What devices are typically used to measure physical activity?

•Pedometer •Accelerometer •GPS watch •Intelligent Device for Energy Expenditure and Activity (IDEEA) •Other devices? phone Work and power Work = force x distance Power = work/time Measurement systems English Metric International (SI)

Introduction

•Sport food and supplement industry booming •Commercial products should be used knowledgably, at the right times, and for the right reasons •Eating food as close to its natural form is the best bet for improving health, preventing disease, optimizing healing, and enhancing performance •Taking a multivitamin and mineral supplement does not compensate for a high fat, low fiber, nutrient-poor diet

What is the most commonly used measure of energy?

•U.S. - calorie •Most of the world -joule 1 gram calorie will increase the temperature of 1 gram of water 1 degree Celsius 1000 gram calories = 1 kilocalorie Expressed ac kcal, kc, Calorie, or as C

Which burns more calories per mile - walking or running? running

•Walking: -About 1 Calorie/kg body weight/mile or 0.45 Calorie/lb/mile @ 2-4 mph •Running: -About 1.6 Calories/kg bodyweight/mile or 0.73 Calorie/lb/mile

Recovery Electrolytes

•When you sweat, lose potassium and sodium •Active people who exercise > 4 hours and athletes who sweat excessively should consume extra salt •First need, replace fluids •Replace sodium and potassium with food Pickles, olives, crackers, soup

Commercial Sports Foods and Fluids

•Which one is best? The one that tastes best to you and settles well in your GI tract •Tend to be more about convenience than necessity •Make fueling easier, take away the guesswork, offer more benefits than plain water •Neither magic nor better than natural foods •Expensive •Homemade sports drink p. 454 •Time and place for engineered sports fuels High level endurance cyclist, marathoner, triathlete who exercises intensely and is limited by sensitive GI tract

Upper GI problems

•heart burn, vomiting, bloating, heaviness of food, stomach pain

Fluids After Exercise

-Goal - replace any fluid and electrolyte deficit -Most active people can recover with normal meals and water -Drinking 50% more fluid than you lost in sweat will enhance rapid and complete recovery from dehydration -If become > 7% dehydrated, likely to need IV fluid Best bet, stay out of medical tent in the first place by knowing your sweat rate and drinking accordingly Sipping is preferable to drinking large amts in one sitting

When is it better to eat high glycemic and low?

-High - best eaten during & after exercise -Low - moderate best eaten prior to endurance exercise

Is CHO fattening?

-Not fattening -excess kcal are (kcal stored as body fat) -body preferentially burns CHO & stores fat

How do you determine if fatigue is caused by iron deficiency?

-Test blood for hemoglobin, hematocrit, and serum ferritin -Ferritin measures iron stores ¤20 µg/dL or higher, preferably 60 or higher -If diagnosed with iron-deficiency anemia, need iron supplements ¤Ferrous sulfate ¤Ferrous gluconate -Do not take iron supplements unless recommended by a physician If serum ferritin stores are low, may be preanemic which can hurt performance If diagnosed with iron-deficiency anemia, will need to take iron supplements (ferrous sulfate or ferrous gluconate); may take 4 months of supplementation to resolve May feel better in 2-3 weeks Should not take iron supplements unless prescribed by physician because too much can be linked to heart disease; 1 in 250 has a genetic condition that makes him or her susceptible to iron overload; have serum ferritin checked > 200 µg/dL signals danger

HMB

By-product of leucine metabolism; helps prevent muscle wasting in chronically ill, hospitalized patients; may reduce muscle protein breakdown and improve recovery in athletes

Cycling study

Cyclists with depleted muscle glycogen stores were able to ex 55 min to fatigue (inability to maintain specified cycling speed on stationary bike) compared with more than twice as long when CHO loaded

Magnesium sources

Nuts, legumes, whole grains, dark green vegetables, seafood, chocolate, cocoa

Calcium sources

dairy products, leafy vegetables, legumes

Intestinal and lower GI problems

gas, intestinal cramping, urge to defecate, loose stools, diarrhea

Monosaccharides

glucose, fructose, galactose

Sodium

helps control water balance

Thiamin

helps convert glucose into energy

UL (Tolerable Upper Limit)

highest level of a daily nutrient that is likely to pose no health risks; above the UL, potential for increased risk

Suggestions for Fueling During Exercise

ideally during exercise lasting > 60 min, you should try to balance your sweat losses and energy output with enough fluids and CHO to keep energy high and blood sugar at normal levels

Calcium

maintains rigid structure of bones

Estimation of Resting Metabolic Rate

males 3-9 (22.7 x bw*) + 495 10-17 (17.5 x bw) + 651 18-29 (15.3 x bw) + 679 30-60 (11.6 x bw) + 879 > 60 (13.5 x bw) + 487 ex: 10% of 1,750 = 175 calories normal range = 2,575-1925 calories/day

Iron in Foods

meats, chicken, fish, liver, legumes

Simple sugars

monosaccharides and disaccharides

GI Distress

•Adverse gut reactions occur in 30-50% of endurance athletes •Common complaints include: -Stomach and upper GI problems -Intestinal and lower GI problems •Hawaii Ironman - of the 362 Hawaii Ironman finishers that ended up in the medical tent in 2004, 63% experienced one or more GI complaints; represents 14% of total field; most common problem was nauses followed by vomiting, diarrhea, and abdminal cramps; GI distress did not correlate with race times or gender