Sports Nutrition
Topics Covered Carbs to Go and Keep Going n Protein to Promote Training n Time-Out for a Drink n Nutrition Before and During Exercise n Nutrition for Recovery n Supplemental Strategies n
Carbs to Go and Keep Going n n n Simple Sugars Complex Carbs Quick and Slow Carbs Stored Glucose and Glycogen Bonking n n n Carbs for Daily Recovery Getting Carbo-Loaded Are Carbs Fattening? Foods Highest in Carbs Counting Carbs CHO vs FAT: A Delicate Balance
Carbohydrates are the primary energy source during exercise n High intensity, short duration (sprint) – > 70% VO 2 max – Anaerobic pathway produces ATP – Muscle glycogen breaks down into glucose for fuel
Recommended Training Diet n n n CHO-rich diet + rest days 60 -70% CHO Choose complex over simple CHOs (unless recovery diet)
Simple Sugars Monosaccharides: 1. Glucose 2. Fructose 3. Galactose
Simple Sugars Disaccharides: Common Name Combination Of. . . 1. Sucrose Table Sugar (Glucose + Fructose) 2. Lactose Milk Sugar (Glucose + Galactose 3. Corn Syrup (Glucose + Fructose) 4. Maltose Malt Sugar (Glucose + Glucose)
Glucose Polymer A chain of 5 glucose molecules n More energy with less sweetness n
Natural Sugars in Some Fruits and Vegetables
Nutritional Value of Sugar
Complex Carbohydrates Complex carbs, such as starch in plant foods and glycogen in muscles, are formed when sugars link together to form long, complex chains, similar to a string of pearls. They can be symbolized like this:
Plants store extra sugars in the form of starch Vegetables (i. e. , corn) convert extra sugar into starch Sweet when it’s young n Becomes starchy as it get older n Fruits (i. e. , banana) convert starches into sugar Green w/some yellow: 80% starch, 7% sugar n Mostly yellow: 25% starch, 65% sugar n Spotted/speckled: 5% starch, 90% sugar n
Complex Carbohydrates Get digested into glucose n Either burned for energy n Or stored for future use as n – muscle glycogen – liver glycogen
The Glycemic Response – food’s ability to contribute glucose to the bloodstream High Glycemic-Index CHOs – quickly enter the blood stream – best to eat during or after exercise – ex. Potato, corn flakes, honey Low to Moderate Glycemic-Index CHOs – slowly enter bloodstream – – desirable prior to exercise bec. Provide sustained energy ex. Rice, banana, apple
Glycemic Index of Some Popular Foods HIGH MODERATE GI LOW FOOD GI Glucose 100 Orange juice 57 Apple 36 Gatorade 91 Potato, boiled 56 Pear 36 Potato, baked 85 Rice, brown 55 Power. Bar Jelly beans 80 Corn 55 Fruit yogurt LF 33 Cheerios 74 Banana, overripe 52 Milk, skim 32 Honey 73 Baked beans 48 Green beans 30 Watermelon 72 Orange 43 Banana, less ripe 30 Raisins 64 Pasta 41 Grapefruit 25 30 -35
Stored Glucose & Glycogen The average 150 -pound male has about 1, 800 -2000 calories of CHO’s stored in the body: Muscle glycogen Liver glycogen Blood glucose Total: 1, 400 calories 80 calories 1, 800 calories
Muscle Glycogen Storage Well-trained muscles develop the ability to store about 2050% more glycogen than untrained muscles. Muscle glycogen per 100 g (3. 5 oz) of muscle: Untrained Muscle Trained Muscle Carbo-Loaded (Costill et al. Am J Clin Nutr 34: 1831 -1836) 13 grams 32 grams 35 -40 grams (Sherman et al. Intl J Sports Med 2: 114 -118)
Does the Glycemic Effect of a Food Really Influence Exercise Performance? Cyclists ate 0. 5 g CHO / lb Pre-Exercise Food Minutes of Exercise Lentils Glucose Water Potato 117 108 99 97 Thomas, Brotherhood and Brand. 1991 Intl J Sports Med, 12 (2): 180 -186
Bonking Depleted MUSCLE glycogen Depleted LIVER glycogen (no blood glucose) “hit the wall” “bonk” or “crash” Despite adequate muscle glycogen, an athlete may feel: n n Uncoordinated Light-headed Unable to concentrate Weak
John, a 28 -year-old runner and banker, faithfully carbo-loaded his muscles for three days prior to his first Boston Marathon n n n On the evening before the marathon, he ate dinner at 5: 00, then went to bed at 8: 30 to ensure himself a good night’s rest As often happens with anxious athletes, he tossed and turned all night (which burned off a significant amount of calories), John woke up early the next morning, and chose not to eat breakfast, even though the marathon didn’t start until noon By noon, he had depleted his limited liver glycogen stores He lost his mental drive 8 miles into the race, and quit at 12 miles His muscles were well-fueled, but that energy was unavailable to his brain, so he lacked the mental stamina to endure the marathon.
Glycogen depletion occurs with repeated days of exercise when CHO intake is inadequate (45 -50%) n For 3 consecutive days – – Subjects ran hard 10 miles Pace: 6 -8 min/mile Ate their standard meals n 45 -50% CHO n Subjects’ muscles became progressively glycogen depleted CONCLUSIONS n Daily CHO rich diet n Rest days required to replete depleted muscles
co ge n (g m/ 10 0 gm tis su e) 0. 5 1. 0 1. 5 2. 0 2. 5 Glycogen depletion occurs with repeated days of exercise when CHO intake is inadequate (45 -50%)
Pat, a 33 -year-old computer programmer experiments with her 2 hour Sunday run:
Rest and Athletic Performance n Forget to rest? Then, risk the following: – injuries – chronic glycogen depletion – chronic fatigue – reduced performance
Getting Carbo-Loaded 55 to 65% cho is appropriate n Too much causes intestinal distress n 4 grams per pound or 9 grams per kg n Taper exercise and eat complex carbs the day before the event and a regular breakfast to keep blood glucose levels high n
7 days before a race Taper workouts by 50 % every second day (allows muscle glycogen to maximize) n Also cut back on calories (less output) n
6 -5 days before a race/event Eat a variety of complex carbs n Continue to reduce intake n Eat frequently 2 -4 hours n Avoid stuffing yourself (excess=fat) n
4 day to go Critical days to top up glycogen n Include bread and grains with meals and eat fruit and fruit juices n Be sure to include protein but watch fat n
3 days to go Training should be minimal n You should start to feel slightly sluggish but relax the extra weight is glycogen (remember it is stored with water) n Expect to gain 2 -6 pounds of water/glycogen weight) n
2 days left Fluids, fluids (using it to pack in glycogen) n A few salty foods to up electrolytes n 2. 5 -4 litres of water/day n
The day before No training n Small frequent meals (graze on complex carbo’s) No huge meals n Avoid gassy foods/irritating foods n No new foods n
RACE DAY ! Eat a light breakfast (keeps blood glucose up) 2 -3 hours before race n Drink consistently 1 -2 cups per hour before n If hungry nibble easily digestible foods ie. Crackers, sports bar n
Are CHOs Fattening? CHOs are not fattening, excess calories are! n n n Fats: 36 cals/ tsp Body stores fat Metabolic cost of converting excess dietary fat into stored fat = 3% of ingested calories n n n CHO: 16 cals/ tsp CHO: energy first Metaboic cost of converting excess CHOs to fat = 23%
Remember this about CHOs 1. Less fattening than fatty foods 2. Muscle fuel 3. Primary fuel during exercise
Foods Highest In CHOs Jim, a 19 -year-old college student, intended to carboload the night before the Newport Marathon. Due to inadequate nutrition knowledge, he “carboloaded” with a pizza supreme. Little did he know that of the 1, 800 calories in the large pizza, 1, 200 were from the protein and fat in the double cheese, sausage, and pepperoni. Only 35% of the calories from the thin crust and tomato sauce were from CHOs. No wonder he felt sluggish during the race!
Counting Carbohydrates Your diet: At least 60% CHO for daily training n 65 -70% CHO before an endurance event n A high-CHO diet should include some fat! n Fill up with CHO then add fat n
CHOs With Hidden Fats
Protein to Promote Training n. How Much Protein Do You Need? n. Protein and the Vegetarian n. Protein Supplements and Amino Acids
The BEST sports diet contains: n ADEQUATE, but not excess protein to – build and repair muscle tissue – grow hair and fingernails – produce hormones – boost your immune system – replace red blood cells
How Much Protein Do You Need?
Protein requirements and muscle mass/strength changes during intensive training in novice bodybuilders 22 -year old men n Lifted weights for 90 min/day, 6 d/wk n Req’d 0. 7 g pro/lb body weight to stay in protein balance n Example: n – 150 lb. Man – Needs 102 g of protein per day Lemon, et al. 1992 J Appl Physiol 73: 767 -775
Calculating YOUR Protein Needs Identify which category you fit into n Multiply your body weight by the range n Example: n – 170 lb. Competitive athlete, adult n n 170 lb x 0. 6 g/lb = 102 g/pro 170 lb x 0. 9 g/lb = 153 g/pro ä 130 lb. Competitive athlete, adult ä 130 lb x 0. 6 g/lb = 78 g/pro ä 130 lb x 0. 9 g/lb = 117 g/pro
Calculating YOUR Protein Needs
Healthfully Including Meat in Your Diet Buy extra-lean cuts of beef, pork, and lamb to reduce your intake of saturated fats n Decrease extra fat n – Drain meat in a colander – Pat dry with a paper towel n Use meat as the accompaniment to a meal
Too Much Protein n n If you fill up with PRO, you won’t fuel your muscles with CHOs Excess PRO increased urination – – – n n Frequent bathroom trips may be inconvenient Increased risk for dehydration Extra work for kidneys $$ Animal proteins tend to be expensive $$ A high PRO diet tends to be high in fat
Protein Supplements and Amino Acids Exercise, not protein, is the key to developing bigger muscles n Beware of extra fat n Expensive muscle-building supplements are not the answer n
Amino Acids: Food vs. Pills
Amino Acids: Food vs. Pills
Nutrition Before and During Exercise n. Guidelines for the Pre-Exercise Meal n. Timing Meals Before Events n. Carbo-Loading for Endurance Exercise n. GI Issues n. Athletes with Diabetes
Magic Meal?
The Pre-Exercise Meal • Varies from person-to-person • Varies from sport-to-sport • No single right or wrong choice Each athlete has to learn through trial and error
Gut Reactions n Adverse effects in 30 -50% on endurance athletes – Stomach and upper GI problems n“heaviness” of food n Heartburn n. Stomach pain n Vomiting n Bloating – Intestinal and lower GI problems n Gas n. Loose stools n Intestinal cramping ndiarrhea n Urge to defecate
Predisposing Factors for GI Problems n n n n Type of sport Training status Age Gender Emotional and mental stress Exercise intensity Precompetition food intake n n n Food taken during exercise Fiber Caffeine & concentrated sugar solutions Level of hydration Hormonal changes during exercise
Pre-Exercise Nourishment n Four main functions – Prevent hypoglycemia Light-headedness n Needless fatigue n Blurred vision n Indecisiveness n – Settle stomach, abate hunger – Fuel muscles – Pacify mind
Guidelines for the Pre-Exercise Meal Every day, eat adequate high-CHO meals to fuel and refuel your muscles n If exercising more than 60 minutes: n – Choose CHOs w/ a moderate-low glycemic effect n If exercising less than an hour: – Snack on foods that settle comfortably
Guidelines for the Pre-Exercise Meal (Con’t) Limit high-fat proteins n Be cautious with sugary foods n Allow adequate time for food to digest n Allow more digestion time before intense exercise than before low-level activity n
Guidelines for the Pre-Exercise Meal (Con’t) Finicky stomach? Experiment with liquified meals n Jitters before event? Eat well the day before n Magic food? Be sure to pack it! n Always eat familiar foods before a competition n Drink plenty of fluids n
Timing Meals Before Events • 8: 00 A. M. Event (I. e. , road race or swim meet) • 10: 00 A. M. Event (I. e. , bike race or soccer game) • 2: 00 P. M. Event (I. e. , football or lacrosse game) • 8: 00 P. M. Event (I. e. , basketball game) • All-day event (I. e. , 100 -mile bike ride, triathlon)
Timing Meals Before Events 8: 00 A. M. Event (I. e. , road race or swim meet) The Night Before n High CHO meal n Extra water At 6: 00 -6: 30 A. M n Light 200 -400 calorie meal n Examples: – Yogurt & banana – 1 -2 sports bars n Extra water
Timing Meals Before Events 10: 00 A. M. Event (I. e. , bike race or soccer game) The Night Before n High CHO meal n Extra water Eat a familiar breakfast by 7: 00 A. M.
Timing Meals Before Events 2: 00 P. M. Event (I. e. , football or lacrosse game) The Night Before n High CHO meal n Extra water Option A: n Big, high-CHO breakfast n And light lunch Option B: n Substantial brunch by 10: 00 A. M.
Timing Meals Before Events 8: 00 P. M. Event (I. e. , basketball game) The Night Before n High CHO meal n Extra water Breakfast & Lunch n High CHO meals n Extra fluids Dinner n By 5: 00 P. M. n Lighter meal between 6: 00 -7: 00
Timing Meals Before Events All-day event (I. e. , 100 -mile bike ride, triathlon) n 2 days prior: exercise 1 day prior: REST Day of: n Eat breakfast n Drink extra fluids n CHO-rich meals n Breakfast n Lunch n dinner Throughout the Day: n Snack every 1. 5 -2 h n Wholesome CHOs n Comfortable meal at lunch n Drink before thirst! n
Sample Liquid Meals Cereal Shake 450 Calories: 60% CHO, 20% FAT, 20% PRO Blend: 2 c. low-fat milk 1 c. favorite cereal Small banana 4 ice cubes Optional: ¼ tsp vanilla, dash cinnamon
Sample Liquid Meals Fruit Shake 470 Calories: 75% CHO, 15% FAT, 10% PRO Blend: 1 c. vanilla yogurt 4 -6 peach halves 4 graham cracker squares Optional: dash of nutmeg
Running on Fuel, not Fumes! Ideal CHO consumption 1 -hr before moderately hard exercise 0. 5 g of CHO/lb 4 -hrs before moderately hard exercise 2 g of CHO/lb Sherman 1989, Sports Science Exchange, Vol 2 (2)
The Game Plan 1 -week prior 1 -day prior Morning of Event During the Event After the Event
1 -Week Prior (review) Goal = load muscle w/ glycogen n Gradually taper training w/ normal diet n Rest 1 -3 days prior to event while eating a high complex CHO diet (5 g/lb of body weight) n May experience weight gain due to water retention n
1 -Day Prior (review) n n n n Eat frequently throughout the day Drink plenty of fluids Avoid gassy foods (legumes, broccoli) Avoid high fiber foods Avoid sugar substitutes Don’t experiment with new foods Eat or drink a bedtime snack Last meal= CHO, moderate PRO & FAT
Morning Of Light or moderate pre-event meal n Endurance athletes n – Eat 1 -4 hours before start time – 50 g/hr n Liquid meals empty faster from stomach
During Event Length & intensity dictate needs n Consume 30 -60 g CHO/hr n If event is greater than 4 hours: n – 60 g CHO/hr in later stages
After the Event Muscle most receptive to reloading glycogen 15 -30 minutes after n 50 -100 g for most athletes n Continue to consume 50 -100 g CHO every 2 hours until next meal n Add PROTEIN to snack to aid repair n It takes 20 -24 hours to replenish muscle glycogen stores n
Running on Fuel, not Fumes! Ideal CHO consumption For a 150 -pound person: 75 -300 g/CHO 300 -1, 200 calories
Carbo Loading for Endurance Exercise Carbo Load Every Day During Training, Not Just Before the Big Event! n Daily Diet – – – 60 -70% CHO Low in fat Balanced w/ adequate PRO n Target: – 4 g of CHO/lb/day
Carbo Loading for Endurance Exercise (Con’t) Do Your Final Hard Training Three Weeks Before Race Day and Start Tapering Your Training at Least Two Weeks Out! n n Reduce exercise time down to 30% of normal Do very little the last 710 days before the event – Do some short, intense speed intervals to keep you sharp n n Tapering can lead to a 9% improvement When tapering, consume same amount of calories as when training to promote glycogen storage
Carbo Loading for Endurance Exercise (Con’t) Include Adequate Protein Along With Carbohydrates n The body needs 0. 60. 9 g or PRO/ lb of body weight everyday n Endurance athletes may burn some protein for energy
Carbo Loading for Endurance Exercise (Con’t) Do Not Fat Load! Goal: 20 -25% fat n Examples: n – Toast w/ jam rather than butter – Pancakes w/ syrup rather than margarine – Pasta w/ tomato sauce rather than oil and cheese
Carbo Loading for Endurance Exercise (Con’t) Choose Wholesome, Fiber-Rich Carbohydrates n n n Promote regular bowel movements Keep systems running smoothly Examples: – – Bran muffins Whole-wheat bread Bran cereal Fruits and vegetables
Carbo Loading for Endurance Exercise (Con’t) Plan Meal Times Carefully n The day before the event: – You may choose lunch as your biggest meal and a normal sized dinner – Allows more time for food to digest and pass through one’s system
Carbo Loading for Endurance Exercise (Con’t) Drink Extra Fluids to Hydrate Your Body n n n 4 -8 EXTRA glasses of water and juice during the 2 days before the event Limit alcohol and caffeine On race morning: – Drink at least 3 glasses of water 2 hrs prior – Drink 1 -2 cups 5 -10 minutes before race time
Carbo Loading for Endurance Exercise (Con’t) On the Morning of the Event, Eat a Breakfast That You Know Will Settle Well Prevent hunger n Maintain normal blood sugar levels n Training = Practice! n
Carbo Loading for Endurance Exercise (Con’t) Be Sensible! n Carbo-load only on – Fruit: diarrhea – Refined white bread products: constipation n Too much last minute training: muscle fatigue n Experiment with new foods: upset system
Eating During Endurance Exercise n Keep your body in balance – Consume enough fluid to match sweat losses – Consume enough CHO Provide energy n Maintain blood sugar n n Significantly stamina by eating 100300 calories (of CHO)/ hour of exercise
Eating During Endurance Exercise n Significantly stamina by eating 100300 calories (of CHO)/ hour of exercise – 0. 5 g CHO/ lb of body weight – Example, 150 lb individual: 75 g of CHO n 300 calories n
Eating During Endurance Exercise Example: • 48 oz of sports drink • 32 oz of sports drink + banana • 16 oz of sports drink + sports bar
Eating During Endurance Exercise (Con’t) Practice eating during training n Have a defined eating plan n Have foods/fluids available n – Pockets – Packs – Friends – Hidden along course
Sports Bars n n n Convenient Portable Promote preexercise eating Most claim to be highly digestible Some are fat-free or very low in fat n n Some boast about a higher fat content Expensive
Sports Bars Vs. Standard Foods
Tournaments and Day-Long Events For the coach: – Instruct regarding the importance of preevent meals and fluids – Enforce between-game eating – Provide healthy snacks during tournament – Pre-select an appropriate restaurant that can healthfully handle the whole team – Instruct players to pack their own favorites
Transit Problems: Constipation and Diarrhea n To prevent constipation – Eat fiber-rich foods – Eat plenty of fresh fruits and vegetables – Drink warm liquids in the morning – Drink more than enough fluids
Some Athletes Struggle with “Rapid Transit” Mary complained, “I have to take toilet paper with me whenever I run. I’m plagued by diarrhea and can’t figure out why. I feel like a detective and have tried to make dietary changes that might correct the situation. I’ve tried to determine what triggers the diarrhea by carefully charting for weeks every food and fluid that I’ve ingested, as well as times I’ve exercised and the times I’ve had diarrhea. I have eliminated suspected problem foods like milk or salads for a week to see if the problem went away, and then looked for changes when I reintroduced these foods into my diet. Nothing. I’ve allowed at least 4 hours between eating and exercise. No difference! I’ve limited broccoli, onions, corn, and other possible hard-to-digest foods. Not a hint of improvement. I have avoided coffee. Worthless. ”
Sports Nutrition Tips for Athletes With Diabetes Consistently eat a proper diet n Exercise on a regular schedule n
Sports Nutrition Tips for Athletes With Diabetes 1. 2. 3. 4. Always exercise after eating Always carry sugar in some form with you Exercise with someone who knows you have diabetes Most often, you should not change your insulin dose for training but should eat more food
Sports Nutrition Tips for Athletes With Diabetes 5. 6. Monitor blood glucose during training Last minute basketball game? ü Eat food before ü May want to reduce your insulin 7. 8. Do not try to carbo-load During long-term exercise, replace glucose supplies regularly
Sports Nutrition Tips for Athletes With Diabetes 9. On a long day trip ü Eat 6 small meals (CHO & PRO) ü Be overprepared w/ extra food 10. 11. Drink plenty of fluids before and during exercise Eat more than usual after exercising
Nutrition for Recovery n. Recovery Fluids n. Recovery CHOs n. Protein & Recovery n. Recovery Electrolytes n. Rest
Billy, a 47 -year-old runner, noticed that he wasn’t recovering from the Boston Marathon as quickly as his peers; he wondered if a poor diet was making the difference. “Preparing for Boston, I ate a blue-ribbon diet. I chose bagels instead of doughnuts, apples instead of potato chips, pasta rather than burgers. I really wanted to run well, and I ran my best time ever – 2: 32. Afterward, I rewarded myself with my standard high-fat junk food diet. I felt tired and abnormally achy for more than a week. If I’d eaten better, would I have recovered faster? ”
Preventing Chronic Fatigue Two or more symptoms = caution! – Unusually poor performances in training and competition – Failure to improve performance – Inability to perform better in competition than during practice – Loss of appetite and boy weight – Insomnia – Joint and muscle pains that have no apparent cause – Frequent colds and respiratory problems – Irritability and anxiety that may be accompanied by depression
Preventing Chronic Fatigue Suggested Solutions 1. 2. 3. 4. Eat a proper sports diet that provides adequate CHO and PRO Allow recovery time between bouts of intense exercise Get plenty of sleep! Minimize stress & disruptive activities
Recovery Fluids
Fluid Replacement: How Much? Weigh yourself before and after training n Goal is to lose 2% of body weight n – Example: 3 lbs. for a 150 lb. Person n Drink on a schedule – 8 oz. Every 15 -20 minutes
Fluid Replacement One pound of sweat = 16 ounces of fluid
Fluid Replacement Luke, a football player, was shocked to discover that on a relatively cool day, he’d lost 8 pounds during a morning football practice – 5% of his body weight and the equivalent of a gallon of sweat! Luke became aware of the importance of drinking more. He started bringing a water jug to practice and drank at every opportunity. He made sure he finished the whole gallon, plus more on hot days. These steps to prevent dehydration helped him recover easily.
Recovery Carbohydrates n Muscles replace glycogen – About 5% per hour – 20 hours to fully replenish depleted muscles n Consume CHO-rich foods and beverages within 15 minutes after a workout – Glycogen-making enzymes are most active – Glycogen replaced from 7 -8% per hour
Recovery Carbohydrates n Target CHO intake for recovery – 0. 5 g per pound of body weight – Every 2 hours – Four 6 -8 hours Example: 150 lb individual 150 lb x 0. 5 g CHO / lb = 75 g CHO = 300 calories CHO
Recovery Carbohydrates n Popular 300 -calorie CHO-rich foods – 8 oz. OJ & medium bagel – 16 oz. Cranberry juice – Soft drink (12 oz & regular) and 8 oz fruit yogurt – One bowl corn flakes, milk, banana
Glycogen Replacement (µmol/g wet wt) Muscle Glycogen Synthesis After Exercise Minutes of Recovery
Protein & Recovery Some PRO can enhance glycogen replacement n PRO (like CHO) stimulates the action of insulin n Ideal Combination: 1 g PRO: 3 g CHO
Recovery Foods: Balancing CHOs and PRO Zawadski et al. , 1992 J Appl Physiol 72 (5): 1854 -1859
Recovery Electrolytes When you sweat, you lose not only water but also some minerals (electrolytes) such as: Potassium & Sodium that help your body function normally
Potassium in Some Popular Recovery Foods
Sodium in Some Popular Recovery Foods
Rest Enhances the recovery process n Reduces risk of injury n Invests in future performances n
Rest n To completely replace depleted muscle glycogen stores muscles need: – Up to two days of rest w/ no exercise – High CHO diet Training: Quality vs. Quanitity
Supplemental Strategies n. Vitamins vs. Food n. Vitamin Supplements n. Minerals n. Energy Enhancers & Magic Potions
Vitamins vs. Food n 75% of athletes use a supplement – 6% male basketball players – 100% bodybuilders
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A supplement should be supplemented with a wellrounded diet
A pill may provide 100% of vitamins But, our bodies also need: – Protein – Minerals – Energy – Fiber – Phytochemicals
Vitamin Supplements: What They Are and What They Aren’t What are Vitamins? n What Vitamins Are Not n Vitamins and Athletes n Supplements for Special Situations n Vitamins as Health Insurance n Beyond Dietary Deficiencies n
What Are Vitamins? “Vitamins are metabolic catalysts that regulate biochemical reactions within your body” The Key… “is to get enough of a vitamin to invest in optimal health, without getting too much and experiencing harmful reactions”
What Vitamins Are Not n No scientific evidence proves that extra vitamins offer a competitive edge – Will NOT enhance performance – Will NOT increase strength – Will NOT increase endurance – Will NOT provide energy – Will NOT build muscles
If performance is impaired by a vitamin deficiency a supplement can correct the problem n However, vitamin deficiencies are usually related to a medical problem that needs medical attention – Anorexia – Unhealthful weight reduction – Malabsorption problems – Years of extremely poor eating habits
Vitamins and Athletes n Does activity increase vitamin needs? – For the most part, No! – Vitamins are catalysts not fuel The more you exercise the more you eat and the more vitamins you consume!
Active People Need More Riboflavin n Riboflavin (Vitamin B-2) – Is important for converting food into energy – Current RDA is 0. 6 mg/1, 000 calories – Active people may need 1. 1 mg/1, 000 calories
Pat, a 46 -year-old office manager, was a tournament golfer. She consumed a well-balanced diet six out of seven days a week. Fridays were her downfall because of fatigue and work stress. She’d inevitably “go off the deep end” and comfort herself with doughnuts, ice cream, and cookies, and then she’d take megadoses of vitamin supplements to protect herself from nutritional deficiencies.
Nutritional Deficiencies Do Not Occur Overnight! n The body stores vitamins – Some in stockpiles (A, D, E, K) – Others in smaller amounts (B, C) n Nutritional deficiencies develop over a long time – Anorexia – Inadequate vegetarian diet
Supplements for Special Situations 1. 2. 3. 4. 5. 6. 7. Restricting Calories Allergic to certain foods Lactose intolerant Pregnant Contemplating pregnancy Total vegetarians Smoking, disease, alcohol consumption
Foods Rich in Folic Acid
Vitamins as Health Insurance People who care enough to take supplements are usually the least likely to need them n Good “insurance” would be a multivitamin/mineral n
Vitamins as Health Insurance Con’t n Megadoses of supplements may lead to toxic reactions B-6 – muscle numbness – Loss of muscle coordination – Paralysis n A – Liver failure – Fractures n C – – – Nausea Abdominal cramps diarrhea
Beyond Dietary Deficiencies n Antioxidants (E, C, beta cartonene, selenium) may prevent – Heart disease – Formation of cancerous tumors
Beyond Dietary Deficiencies n To get 100 IU of Vitamin E – 2 cups of almonds – 7 cups of peanuts – 2 cups of olive or corn oil – 6 cups of kale – 4 cups sweet potatoes – 19 cups of spinach
Guidelines for Dietary Supplements
Guidelines for Dietary Supplements
Minerals are present in all living cells. They occur freely in nature in the soil and water, and travel through the food chain by being absorbed into the plants that grow in the soil and then into the animals that consume the plants and water. Vegetables of the same species can differ in mineral content, depending on the soil in which they were grown.
Minerals n Calcium – Bone formation & strength – Nerve impulse transmission – Muscle contraction n Potassium & sodium – Water balance n Iron – Oxygen transport n Magnesium – Activates enzymes – Muscular contraction n Zinc – Growth & healing
Iron A necessary component of hemoglobin, the protein that transports oxygen from the lungs to the working muscles n Iron deficient likely to easily fatigue upon exertion n
Iron n Athletes at highest risk of iron deficiency anemia: – Female athletes who lose iron through menstrual bleeding – Athletes who eat no red meat – Marathon runners may damage red blood cells from ground force reaction during training – Endurance athletes significant iron loss through heavy sweat losses – Teenage athletes may not meet requirements for growth and activity
Getting Enough Iron n Eat lean cuts of beef, lamb, pork, & dark meat of skinless chicken or turkey 3 -4 times /week Select breads & cereals that are “iron-enriched” or “iron fortified” Eat these foods with Vitamin C n n Use cast-iron Avoid coffee & tea during meals
Too Much of a Good Thing n Iron Overload – Risk factor for heart disease and attacks – May promote production of free radicals – May be associated with arthritis and diabetes – Occurs in about 1/250 people
Zinc & Chromium n Zinc – Help remove CO 2 from muscles during exercise – Enhances the healing process – Better absorbed from animal protein than plants n Chromium – Helps transport insulin from blood to muscle cells – Thus, involved in: n n n Transportation of amino acids into muscles Burning of fat Glycogen storage
Energy Enhancers and Magic Potions Placebo Effect
Can extra branch-chain amino acids prevent the mental fatigue that is associated with exhaustion? 1. 2. 3. 4. Research offers mixed opinions Low doses: little effect on brain serotonin Large doses: unpalatable, may lead to dehydration or a toxic reaction Recommendation: Consume plenty of CHOs
Do extra branch-chain amino acids enhance recovery from exhaustive endurance exercise? Possibly, but more research is needed
Will creatine enhance performance in athletes who do short bursts of highintensity exercise? 1. 2. 3. Possibly Creatine occurs naturally in meat & fish Creatine phosphate is used by the muscles to generate energy for 1 -10 seconds of intense work
Is “fat-loading” a valid dietary recommendation to enhance stamina? 1. 2. 3. 4. No. Yes, hard training helps your muscles adapt to greater fat burning. Eating excess dietary fat does not enhance endurance. Exhaustion correlates with CHO depletion
Too Good to Be True? n n n Is the “research” cited from professionally respected journals? Are claims based on research done on athletes, not rats or sick people? Are the claims valid but taken out of context? Are claims based solely on anecdotes or testimonials? Is there an authorized endorsement from a prestigious university or medical center?
The BEST Energy Enhancers Without a doubt, a proper sports diet with adequate fluids and CHOs is the best investment in top performance Your dietary goals are to prevent dehydration and maintain normal blood sugar
The BEST Energy Enhancers n n n Be well fueled every day so you can train at your best (3 -5 g CHO/lb/day) Stay hydrated & drink extra before and after exercise Consume CHO & fluid during exercise lasting longer than 60 -90 minutes Reload CHOs after exhaustive exercise REST – so muscles can refuel and recover
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