Nutritional Considerations

Nutritional ConsiderationsIntroductionResearch shows that, regardless of the sport, an athletes diet plays a critical, if not essential, role in performance.Yet misinformation and misconceptions persist among coaches and athletes regarding what constitutes an adequate diet.We will first examine available evidence concerning the dietary knowledge and practices of coaches and athletes.Then we will examine dietary recommendations for healthy eating, including the roles of carbohydrates, proteins, fats, vitamins and minerals.IntroductionNext, we will look at evidence pertaining to protein supplementation and other ergogenic aids.Special attention will be given to the sport of wrestling, which has been plagued with the problem of athletes attempting to lose body weight rapidly by dehydration, and a simple method is provided to assess an athletes ability to rehydrate adequately. We will discuss the relationship between nutrition and recovery from injury.Finally, we will use our 3 day calorie tracker to incorporate into our fitness program in the computer labA brief history of sports nutritionSpecific text on the diet of ancient athletes are rare.Human muscle energy metabolism began to be studied in the late 19th century

Milo of Croton 6th century BC Was the first Olympian Would consume 20 pounds of bread and meat a day= 16,000 calories/dayNathan Zuntz 1911Was a psychologist who discovered you need to combine carbohydrates and fat together to help increase energyBoston Marathon Studies 1923A group of scientist we called in to test marathon runners after their race.Their conclusions found that the majority of marathon runners had low blood sugar levels after the race. Low blood sugar levels = hypoglycemiaIn the next Boston Marathon, a few runners were encouraged to consume high-carbohydrate food. Conclusion = consuming high carbohydrate prevented lower glucose level and improved running time to complete the raceHarvard Dog Studies 1932Scientist took 2 sled dogs Increased the sled dogs food for 4 hours, 6 hours, 17 hours, 23 hoursProvided more carbohydrates after the rest periodDr. Robert Cade 1965An ephrologist (kidney specialist) who studied physiology of exerciseCame to University of Florida College of MedicinePut together a team who began to work on answering the famous question asked about the football teamWhy dont football players urinate after a game? At the time, basic exercise wisdom discouraged athletes from replenishing liquids lost due to sweating during the gameThe team lost so much fluid, that they had none left to form urineDr. Robert Cade began to develop a hydration drink (combined with sugar and salt) that could be absorbed more quickly. Thus, this became the basis of Gatorade

He first used Gatorade on guinea pigs(who were the JV squad)Noticed that in the scrimmage during practice the Varsity would over power the JV teamAfter consuming the Gatorade beverage, in the second half, JV overpowered V

IntroductionProper nutritional knowledge is imperative for all individuals, but especially for those involved in athletic competitions (Jacobson, Sobonya, & Ransone, 2001).An athletes diet has a direct impact on performance, recovery from training and competition, resistance to environmental extremes, recovery from injury, and, to some extent, likelihood of injury.In essence, diet influences virtually all aspects of sports participation.Most athletes (68%) were familiar with the food groups and 71% reported incorporating them into their diet, but Parr et al. (1984) also demonstrated that athletes largely relied on parents for information about nutrition followed by TV commercials and magazines.Although the knowledge of most parents concerning nutrition cannot be measured, it is probably safe to assume that both parents and the media represent, at best, marginal sources of current nutritional advice always or often during their college carriers. Nutrients: An OverviewAccording to the American Dietetic Association (2009), eating correctly for sports performance willHelp the athlete train longer and at a higher intensityDelay the onset of fatigue Promote recoveryHelp the athletes body adapt to workoutsImprove body composition and strengthEnhance concentrationHelp maintain healthy immune functionReduce the chance of injuryReduce the risk of heat cramps and stomachaches Although a comprehensive investigation of both macronutrients (required in large amounts) and micronutrients (required in small, or trace, amounts) is beyond the scope of this text, a brief review of the six classes of nutrients is presented.Carbohydrates, fats, and proteins are the macronutrients, and each is important in the diet.The mix of these may change based on fitness levels, exercise goals, and personal food preferences.Vitamins and minerals are micronutrients that contribute to metabolic reactions and tissue structure.And finally, water is essential for substrate transport, waste removal, and joint health (McArdle, Katch & Katch, 2009).

CarbohydratesCarbohydrates (CHO) are molecules that, by way of their metabolic breakdown, provide energy for high-intensity exercise.The specific forms of CHO used within the body are glucose and glycogen (the storage form of glucose) found in the blood, liver, and skeletal muscle.

CarbohydratesCarbohydrates consist of carbon, hydrogen, and oxygen atoms, with the number of carbon atoms ranging from three to seven.They fall into three general categories, based on the complexity of the molecule. the simplest forms of CHO are the monosaccharides (a single molecule), which include sugars such as fructose, glucose (blood sugar), and galactose.

CarbohydratesThe next group is the disaccharides (two monosaccharide molecules combined), which include commonly known sugars such as lactose (milk sugar), sucrose (the most common form of sugar in the diet), and maltose.The complex carbohydrates are known as polysaccharides (10 to thousands of monosaccharides linked together) and include compounds such as glycogen, starch, and cellulose (dietary fiber).

CarbohydratesThe majority of dietary CHO is derived from plant sources, primarily grains, seeds, fruits, and vegetables.In a practical context, carbohydrates are classified as either simple (monosaccharides) or complex.In general, complex CHO contain more nutrients and fiber than simple CHO do.The most common form of dietary CHO intake is from simple sugars, primarily foods high in sucrose Soft drinks, candies, and cereals (high in sugar).CarbohydratesAlthough high in caloric content, these foods stimulate insulin release , cause fluctuations in blood glucose levels, and provide little in any way of other nutrients; therefore, they are often referred to as empty calorie foods.CarbohydratesA superior form of dietary CHO is derived form eating more complex CHO or whole-grain cereals and breads, vegetables, and fruits.The CHO in these foods is in the form of starch found in the cereals and breads or cellulose found in leaves, stems, roots, seeds, and coverings of plants.An added benefit of consuming complex CHO is that they typically contain dietary fiber (indigestible CHO), which may lower cholesterol absorption and is also beneficial to the digestive tract.Daily fiber intake should be between 21 g and 38 g depending on gender and age (McArdle et al., 2009).CarbohydratesAnother excellent source of CHO is fruits, which can provide a significant amount of CHO in the form of fructose.Fructose, a monosaccharide, is much sweeter than surcose; however, the benefit of fructose is that it does not stimulate pancreatic insulin secretion and, as a result, helps to stabilize blood-glucose and insulin levels (McArdle et al., 2009).

CarbohydratesAn added benefit of whole-grain breads, cereals, fruits, and vegetables is that they typically contain a wide variety of other nutrients and, as such, help to provide a balanced diet.

CarbohydratesAlthough the classifications of simple and complex CHO often are suitable to describe foods containing CHO, these classifications do not represent the way both simple and complex CHO are hydrolyzed and absorbed by the body (Manore, Meyer, & Thompson, 2009)Foods are now also classified as producing either high, moderate, or low glycemic responses.Foods classified as having a high glycemic response typically result in a large and rapid rise in blood glucose and insulin, followed by a rapid decrease in blood glucose.CarbohydratesThose foods with a lower glycemic response cause a steadier rise and decline in blood glucose and insulin.Low glycemic index CHO improve diabetes management, reduce the risk of heart disease, reduce hunger and keep a person fuller for longer, and prolong physical endurance, whereas high glycemic CHO help refuel carbohydrate stores after exercise.

Carbohydrate & MuscleMuscles require CHO as a fuel source during exercise.The recommended percentage proportion of CHO in the diet should range between 60% and 70% of the total calories consumed daily, depending on the exercise frequency and intensity.Regardless of the type of CHO consumed, they all provide approximately 4 kal/g CHO.The average person stores approximately 1500 to 2000 kcal of CHO, the majority of which is in the form of muscle and liver glycogen, with a small portion available and blood glucose (McArdle et al., 2009).CarbohydratesAll individuals need to consume carbohydrates to maintain body functions or support exercise; however, athlete engaging in different activities need to consume carbohydrates at greater levels than sedentary individuals do.

Carbohydrate (Glycogen) LoadingAs stated earlier, the majority of CHO in the body is stored in the skeletal muscles and liver in the form of glycogen.Physiologically, it is to the athletes advantage if the total amount of stored glycogen can be increased prior to a competition.Athletes involved in aerobic sports, especially those with durations in excess of 60 minutes, benefit the most from an increased level of stored glycogen.Carbohydrate (Glycogen) LoadingEssentially, the process of CHO loading involves the systematic decrease of dietary CHO intake in conjunction with a significant increase n exercise intensity.Early procedures for CHO loading were particularly Spartan in nature, requiring multiple days of intense exercise (depletion phase) combined with dietary restriction of CHO intake.

Carbohydrate (Glycogen) LoadingIronically, although such protocols often did result in an increase in stored glycogen, the negative impacts often outweighed the benefits in performance.These included severe physical fatigue associated with the depletion phase, along with negative emotional changes such as hyperirritability.In addition, another problem related to CHO loading is that for ever gram of CHO stored, an additional 2.7 g of water is also stored.As such, the process of CHO loading results in an overall increase in body weight that, in sports such as distance running, may represent a performance detriment.Carbohydrate (Glycogen) LoadingResearch verified that a properly executed regimen of CHO loading can boost the level of stored glycogen from the normal 1.7 g of glycogen/100 g of muscle tissue to 4 to 5 g of glycogen/100 g of muscle tissue.A typical modified regimen begins approximately one week prior to competition and includes a gradual tapering of physical activity accompanied with a slight increase in CHO ingestion.Exercise (75% maximal O2 consumption over the first 3 days follows a steady decline in total time 1.5 hrs/day to 50 mins) while CHO consumption is maintained at 50% of total caloric intake.

Carbohydrate (Glycogen) LoadingOver the next 3 days, exercise time is decreased to about 10-15 minutes while CHO consumption is increased to 75% of total caloric intake.A normal protein and fat intake is maintained.A high-CHO meal is then consumed on the day of the competition (McArdle et al., 2009)

http://www.youtube.com/watch?v=heQ5eukh8t8

Carbohydrate and ExerciseCHO stored in muscle and liver as glycogen-350 grams in muscle; - 90 grams in liver-1800 calories in allTrained muscle can carry more glycogenSmall amount circulating as blood glucoseExcess CHO stored as fat when glycogen stores are full

(Jon Vredenburg, MBA, RD, CSSD, LD/N, HFS)

Carbohydrate and ExerciseHigh intensity makes CHO the preferred substrate.50-60% of energy over 1-4 hours of continuous (70% capacity) exercise comes from CHO.Since CHO is a primary fuel source low levels lead to fatigue.Fatigue = when exercise continues to the point that compromises liver and muscle glycogen supply.2 hour strenuous workout can deplete liver and muscle glycogen.

(Jon Vredenburg, MBA, RD, CSSD, LD/N, HFS)Carbohydrate and ExerciseRate of ingested carbohydrate oxidation is limited to -60 grams per hour (240 calories).Intestinal transports become saturated.CHO combinations (i.e. glucose +fructose) have greater oxidation rates.Overall carbohydrate oxidation rates usually well above 500 calories/hour.In moderate to higher intensity activities.Clarifies the need for adequate fueling throughout training cycles (between sessions)

Jeukendrup. A (ED) (2010). Sports Nutrition from lab to kitchen, Meyer & Meyer SportWhere the fuel could be used*Brain storage has 20% at restFat (Lipids)Fats serve a variety of functions in the body, including:Providing energy for muscle contractionInsulationPrimarily in the form of subcutaneous fatProtection of vital organs such as the kidneys and heartDietary fats are either simple or complex, depending on their specific molecular structure.Fats, like CHO, consist of carbon, hydrogen and oxygen atoms; however, the ration of hydrogen to oxygen is far greater in fats than in carbohydrates.Fat (Lipids)Depending on their molecular structure, fats can exist either in liquid (oils) or solid form.Simple fats consist of two compounds:GlycerolFatty acidCan be either saturated or unsaturated

Fat (Lipids)The term saturated describes the fact that in this form of fat all of the available bonding sites on the fatty acid molecule are occupied by a hydrogen atom.Most dietary sources of saturated fats are derived from animal sources (i.e. beef, pork, poultry, and dairy products) and are generally solid at room temperature.

Fat (Lipids)Unsaturated fats, as the term implies, are structured in such a way as to prevent all of the available bonding sites from being occupied by a hydrogen atom.The majority of unsaturated fats exist in two forms, monounsaturated and polyunsaturated.

Fats (Lipids)Monounsaturated fatInclude a single site on the carbon chain where a double bond exists, thus preventing hydrogen atoms from bonding at the site.

Polyunsaturated fats Have two or more double bonds and, as such, have at least two sites that cannot be occupied by hydrogen atomsFat (Lipids)The recommended percentage proportion of fats in the diet should be 30% or less of the total calories consumed daily (McArdle et al., 2009).It is recommended that saturated fats make up only 10% of total fats (20-25g based on 2000 2500 kcal/day); therefore, the majority of fats consumed should be unsaturated.This helps avoid the problems attributed to excessive consumption of saturated fats, including high cholesterol and cardiovascular disease.

Fat (Lipids)Dietary sources of fats, as stated earlier, are animal products such as beef, poultry, and pork.Other sources include dairy products, such as milk, butter, and cheese.In addition, plant sources of fats include nuts and plant oils such as corn oil, olive oil, and soybean oil.

Fat (Lipids)In addition to CHO, fat is an important source of energy during rest and exercise.Both CHO and fats are oxidized for energy at the same time.The proportion of energy that comes from CHO and fats is dependent on the duration, intensity, and type of exercise as well as the athlete's fitness level and meal eaten prior to exercise (Manore et al., 2009).Regardless of the type of fat consumed, all forms provide approximately 9 kcal/g; therefore, fats are calorie dense.Fat (Lipids)One tablespoon of butter has the same kilocalories as 4 cups of chopped broccoli (100 kcal).The available amount of energy in the form of stored body fat is significantly greater than what is available from CHO.For example, the available energy in a 70-kg person who has 18% body fat is calculated to be around 113,400 kcal.Fat and ExercisePotentially unlimited source of fuel during aerobic exercise.150 pound (68 kg) runner in a marathon at a 8 min/mile pace burns 3245 kcal.One pound of fat = 3500 kcal.Improving fatty acid oxidation during exercise preserves muscle glycogen.Result of training adaptations.

Fat burning, simplifiedFatty acids broken down in the mitochondria generate Acetyl CoA entry in the Krebs (TCA) cycle.Accumulation of Acetyl CoA occurs in absence of carbohydrate.Physical activity becomes compromisedCarbohydrate substrates needed to sustain Krebs CycleFat burns in a carbohydrate flameProteinAs with both carbohydrates and fats, proteins also contain carbon, hydrogen, and oxygen atoms in their molecules.However, proteins also include nitrogen and, as such, they are unique molecules compared to the other nutrients.Protein molecules are assembled by combining amino acids using peptide bonds to form large, complex molecules.The majority of the bodys protein is found in muscle and connective tissues.Proteins are also found in the body fluids and in the blood from thousands of different enzymes and structures related to blood clotting such as fibrin and fibrinogenProteinIn addition, muscle protein is used as an energy source during prolonged exercise, producing as much as 10% to 15% of the energy requirements for long duration activity.Research suggests that a regimen of regular aerobic exercise enhances the bodys ability to generate energy from the metabolism of proteins (Sumida & Donovan, 1995).

ProteinThe body builds proteins from the amino acids that are available from the protein that is consumed in the diet.Of the 20 amino acids required to construct the bodys proteins, 8 cannot be synthesized by the body and must, therefore, be ingested in the diet.

ProteinThese eight amino acids are known as essential, implying that they must be present in the diet.They are isolucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.The best dietary sources of the essential amino acids are eggs, meats, and dairy products, all known as complete proteins.Incomplete proteins are those that lack one or more or contain insufficient amounts of one or more of the essential amino acids.ProteinThey include foods found in the legume and grain categories.Athletes who are on vegetarian diets must take care to eat foods in the correct combination to provide all of the essential amino acids.A solution to the problem is for such athletes to include either eggs (ovolactovegetarian), milk products (lactovegetarian), or both to ensure adequate supplies of essential amino acids.ProteinSubstance in foods made up of chains of amino acids (AA)Three categories of AA:EssentialNonessentialConditionalBuild, repair and maintain body tissuesProvide energy if carbs and fats are in short supply4 calories per gramProtein SupplementationBecause dietary protein is associated with building muscle mass, many athletes are curious about the benefits of extra protein consumption beyond that found in regular diets.A recent study of 61 high school football players reports that 64% are ingesting protein supplements in an attempt to gain strength or improve performance (Duellman et al., 2008).Unfortunately, the researchers also present the more than 60% of these athletes believe there are no risks to excessive protein intake.Protein SupplementationHowever, at least two problems are associated with the practice of consuming additional protein.The first is that many sources of dietary protein also contain a large amount of saturated fat, such as beef and pork products.The second problem is that in certain cases the body may be unable to eliminate the by-products of excess protein breakdown efficiently, and, as such, organs such as the liver and kidney are stressed.Protein SupplementationToday there is a huge commercial market for what are commonly known as protein supplements, often sold at health food stores, grocery chains, and sporting good stores and through mail order and the Internet.Most of these products consist of meat by-products that are processed into a powder form that is then mixed with water or some other liquid and consumed orally.Unfortunately, because these products are marketed as food supplements, their purity is not monitored by the Food and Drug Administration.Protein SupplementationIn addition, many of them are extremely expensive on a per-pound basis, often exceeding the cost of more common sources of protein such as meat and dairy products.

http://www.youtube.com/watch?v=ZRgZuS_U9TQ

Protein SupplementsUnfortunately, there is virtually no scientific research that supports the premise of protein supplementation enhancing muscle development.Muscle mass does not increase simply by eating high-protein foods or special preparations of amino acids (McArdle et al., 2009).Protein SupplementsAt present, available research indicates athletes involved in intense training, particularly strength training, need to consume between 1.2 g and 1.8 g of protein for each kilogram of body weight, whereas the sedentary person or light exerciser needs to consume only 0.83 1.2 g/kg.To put this into a practical context, the calculated protein requirements for a 60-kg would range from 72g to 108g per day.Eight ounces of broiled salmon provides approximately 62 g of protein, 8 ounces of lean sirloin steak provides approximately 65 g of protein, and 8-ounce skinless chicken breast yields a little over 70 g of protein

Protein SupplementsIt can be seen that adequate protein to meet the daily requirements of an athlete in heavy training can easily be achieved through meals without the need of additional supplements.

Only growing infants and children, pregnanat or nursing women, or adults suffering from certain disease or injury states should consume more than the recommended amount (McArdle et al., 2009).Proteins and ExerciseProtein used for growth and repair of tissue.If overall caloric intake is adequateProtein energy contribution to exercise inversely proportional to available energy stores.Usually accounts for a small (>5%) amount of ATP formed during endurance activity VitaminsVitamins are chemicals that are needed by the body in relatively small amounts and, therefore, are classified as micronutrients.This should not be interpreted, however, to mean that vitamins have little importance nutritionally.On the contrary, adequate amounts of vitamins are essential to health and human performance.Vitamins serve a multitude of functions in the body, essentially helping to regulate biochemical reactions such as energy metabolism and cell and tissue generation, as well as serving antioxidants (antioxidants protect structures such as cell membranes from the damaging effects of free radicals that are released during vigorous exercise).VitaminsVitamins contain no caloric value and, as such, do not directly provide energy for muscle contraction.

VitaminsSo far, 13 specific vitamins have been identified and are divided into two groups:Water solubleFat soluble

VitaminsWater-Soluble group includes:Vitamin C (ascorbic acid)The B vitaminsB1, B2, B6, B12NiacinFolic acidBiotinPantothenic acidWater soluble vitamins, with the exception of B12, are not stored in the body, and excess amounts are excreted via the kidneys and urine.VitaminsFat-soluble vitamins:Vitamins A, D, E, KBecause of their solubility, they are stored in the fat tissues of the body.In fact, excess consumption of fat-soluble vitamins beyond what is recommended (in the United States Allowance [RDA]) can result in buildup of and eventual toxic reaction to the stored vitamin (McArdle et al., 2009).VitaminsThere is no evidence that taking any vitamin in an amount greater than the recommended level provides any sort of performance enhancement.Athletes who consume balanced diets most likely are getting adequate amounts of vitamins through their food and beverage consumption.For athletes who are eating less than an ideal diet, a daily multivitamin supplement that meets the RDAs for all necessary vitamins is advised.There is no evidence that vitamins marked as organic or natural provide any benefit over those that are manufactured synthetically and often sold at a lower cost.VitaminsTo be effective, vitamins should be taken after meals to optimize absorption because they work best in the presence of other nutrients.

VitaminsKey regulators in energy metabolismOffer protection against oxidative damageSupports growth and developmentIf take too many may have a reverse effectMineralsMinerals are elements that must be consumed regularly to ensure normal body functions.They provide structure, help maintain normal heart rhythm, assist muscle contractility, promote neural conductivity, and regulate metabolism (McArdle et al., 2009).A typical over-the-counter daily vitamin and mineral supplement usually includes many minerals.As is the case with vitamins, there is no scientific evidence that consuming minerals in excess of the RDA provides that advantage in performance.In addition, a well balanced diet can provide all the necessary dietary minerals.MineralsThe best known minerals are iron and calcium.Perron and Endres (1985) investigated the nutritional habits of 31 female high school volleyball players.Seventy percent (70%) of them did not meet the RDAs for energy (total calories), calcium, and iron. Iron is associated with red blood cell formation, oxygen storage and transport, and enzymatic reactions related to protein and carbohydrate metabolism.

MineralsIron is available from plant and animal sources.It is best absorbed from animal sources.RDA for iron is 10 mg for males and 18 mg for females.Females require more iron than males, especially during their first menstrual cycle.Inadequate intake of iron or limited rates of iron absorption can cause anemia, resulting in lethargy and shortness of breath.Physically active individuals need only include the RDA levels of iron in their daily diet; they should steer clear of supplements unless a deficiency exists because excess iron can be very toxic to the body (McArdle et al., 2009).

MineralsHowever, endurance, vegetarian, and female athletes may want to consult a physician for assessment and maintenance of proper iron balances.Current thought among sports scientist is that iron deficiency is common in athletes involved in endurance sports (Pattini & Schena, 1990).It is speculated that iron may be lost through sweating, gatrointestinal bleeding, menstrual bleeding, and excessive red blood cell distribution (hemolysis) in the blood vessels.MineralsA convenient method of supplementation is a daily multivitamin and mineral tablet.Numerous products are available over the counter that provide the adult RDA of iron.

MineralsCalcium is metabolically associated with normal bone and dental health.It is the most prevalent mineral in the body and is easily obtained in the diet by consuming diary products or other foods/beverages that have been artificially fortified with calcium.

MineralsScientific evidence suggests that some groups of athletes may be at an increased risk of calcium deficiency (Deuster et al., 1986; Moffatt, 1984).Female athletes involved in aerobic running sports, as well as gymnasts, have been found to be consuming too little calcium.This places these people at risk for inadequate bone development and can contribute to osteopenia or osteoporosis in later life.In these high-risk groups, calcium supplementation is most certainly warranted. MineralsAgain, it is important to note that a supplement that provides the RDA is appropriate because consuming calcium in excess of this level may lead to other problems.The recommended daily dosage for adolescent females is 1500 mg.

MineralsServe as structural components of the bodyMajor minerals and trace mineralsStimulate muscle and nerve activity as well as hemoglobin synthesisElectrolytes regulate fluids in and out of the cellsSodium and PotassiumMaintain relative acidity or alkalinity of blood and tissueControl acid-base balanceWaterThere is virtually no debate in the sports medicine community regarding the importance of water, not only to human performance but to survival as well!Water .WaterHoused in two general locations:Are extracellular fluidsThose .Intracellular fluids Those .Water is constantly being lost through normal body functions .WaterAt rest the adult .Under conditions of heavy exercise, especially in conditions of high ambient temperature, water requirements can escalate to 5 L to 10 L daily (McArdle et al., 2009).During exercise, a significant amount of body water is lost to eliminate metabolic heat.The circulatory system transports this excess heat by way of the blood to the skin, where, .WaterThe process of sweat evaporation from the skin surface can easily result in .The most serious consequence of profuse sweating is .A reduction of body weight of 2-5% can result in reduced performance and stress on internal organs.

WaterTo calculate the reduction in body weight due to fluid loss, .Take the number of pounds lost in activity and divide the number by the pre-practice weight.This .Current recommendations suggest that for every pound of water weight lost, an athlete should consume 20 24 oz of fluid (McArdle et al., 2009).

WaterSummaryOne .Even a 2% water deficit can impair performance.Hydration status influenced by:FitnessIntensityTemperatureClothingacclimation.Jeukendrup. A (ED) (2010). Sports Nutrition from lab to kitchen, Meyer & Meyer Sport

Water..SummaryProper hydration = .There is no one fits all amountWeight (in pounds) / 2 = Ounces Water needed at restGeneral guideline

Jeukendrup. A (ED) (2010). Sports Nutrition from lab to kitchen, Meyer & Meyer Sport

Sweat CompositionPhysical Sweat contains 1 liter of sweat could contain up to 2 grains of sodiumPotential for sodium imbalance main concernCramping intervention

Bernadot, D. (2006). Advanced Sports NutritionSweat Mineral CompositionSodium460-1840 mg/LChloride710-2840 mg/LPotassium160-390 mg/LMagnesium0-36 mg/LCalcium0-120 mg/L

Dunford. M. (Ed). (2006) Sports Nutrition: A practice mineral for professionalsHydration GuidelinesBefore exercise: During exercise: After exercise:

Source: American College of Sports Medicine. www.acsm.orgExtreme ConditionsPhysical fitness dictates heat toleranceHigh body fat = Problems Have an emergency action plan (EAP)Acclimatization: Sweat starts at a lower core temperatureReduction in salt losses in sweat; more sweat produced Typically takes two weeksSports DrinksContain Adding protein has had equivocal resultsMany flavors and variations8 ounce serving50 calories14 g CHO110 mg sodium30 mg potassium

Saunders, M. Kane. M (2004). Effects of a carbohydrate-protein beverage on cycling endurance and muscle damage.Sports DrinksThe Cool and non-carbonatedSodiumProvides the drive to drink; maintains proper sodium balanceCHOAt concentrations High CHO content leads to GI distressMultiple Maltodextrins used to enhance palatability (less sweat)Sports Drink vs. WaterWater As intensity and duration increase sports drinks are preferredExogenous energy source aids performanceSweat RateAmount of sweat lost in an hourDetermine pre-exercise weight Determine activity16 oz = 1 poundDetermine post-exercise weightProvides individualized guidance

Sweat Rate RehydrationHelps Under-hydration Rehydrate with an amount greater than the lossesSpecial Considerations..Female AthletesAs more women become involved in organized sports, concerns .Perron and Endres (1985) find that 81% of female volleyball players report a concern about body weight; perhaps their low caloric intake was part of an attempt to lose weight.

Special Considerations..Female AthletesLoosli and Benson (1990) surveyed 76 adolescent female gymnast and their results indicate that .Special Considerations..Female Athletes Because gymnastics place great emphasis on being lean, .However, gymnastics is not alone.It was also reported that 47% of athletes in lean .X-Country and Endurance SportsUpgrove and Achterberg (1990) investigated the nutritional habits of male and female high school cross country runners.Ironically, .In addition, they reported that coaches were their preferred source of information on nutrition.WrestlingThe sport of .Wrestling is one of only a few sports that match participants on the basis of weight.Yet, .Unfortunately, the only form of rapid weight loss, short of surgical removal of tissue, is through dehydration.WrestlingWater weights approximately .Wrestlers have been known to use a variety of methods to rapidly lose weight, including fluid restriction, the use of laxatives and diuretics, artificially induced sweating, and even starvation.WrestlingThere is no definitive proof that such tactics actually present an advantage, and there are plenty of reasons not to engage in such behavior.The .The long-term effects are not known at this time; however, there is speculation in the scientific community that these techniques may interfere with normal growth and development of the adolescent athlete.

WrestlingIn an effort to reduce the likelihood of unhealthy weight-loss practices (weight cutting) in high school wrestlers, the state of Wisconsin instituted the Wrestling Minimum Weight Project (WMWP) in 1989 (Oppliger et al., 1995).This project involved the establishment of minimum weight-loss and body-composition criteria that limit all participants to a body fat minimum of 7% and a maximum of 3 lb of weight loss per week.

ConclusionsMany athletes do .Carbohydrate consumption should be 6-10 g/kg body mass (2.7-4.5 k/lb body weight). Carbohydrates maintain blood glucose levels during exercise and replace muscle glycogen. .ConclusionsProtein recommendations for endurance and strength-trained athletes range from 1.2 to 1.7 g/kg body mass (0.5-0.8 g/lb body weight.) .For example, to compute the recommended 1-day protein intake for an 85-lb female gymnast, make the following calculations:Body weight in kilograms = 38.6(85 lb / 2.2 lb per kg)=46.4 g daily protein requirementA chicken breast (8oz) will provide the protein requirementConclusionsFat intake should range from 20% to 30% of total energy intake. .Athletes participating in sports that stress lean builds and low body fat tend to follow diets too low in total calories. .

ConclusionsAthletes tend to consume too many calories in the form of junk food, which is laden with fat and extra protein.Many athletes diets are deficient in at least some important minerals, such as calcium, iron, and zinc. However, the . (McArdle et al., 2009). Exercise and MetabolismATP is the energy currency of the bodyPower Three different energy systems to get ATPPhosphagen systemVery short termAnaerobic systemShort termAerobic systemUnlimited capacity to make ATP

Hargreves, M & Spiret L (2006)

Phosphagen System..Used in short burst of exerciseAnaerobic Phosphate group removed by creatine kinaseLimited amount of PCr stored in muscle tissueEnergy supply lasts about 8 to 10 seconds

McArdle W. Katch, F & Katch V (2005) Sports and Exercise NutrtionAnaerobic GlycolysisAlso known Stored glycogen is converted to energyCan provide energy for about 90 120 secondsATP is made with pyruvate as an end productLactic acid is formed from pyruvateATP

McArdle W., Katch F & Katch V (2005) Sport & Exercise NutritionAerobic SystemAfter With oxygen present, gerater yield of ATPFuel sources with aerobic respirationMuscle glycogenLiver glycogenExogenous fuelFatty acids, (proteins)

McArdle W., Katch F & Katch V (2005) Sport & Exercise Nutrition

Eating for MuscleAdding Anabolism = constructive metabolismProtein needs are increased to double RDAUse

McArdle W. Katch, F & Katch, V (2005). Sports & Exercise NutritonEating for MuscleGaining Fuel basal needs, activity and growthHarder gainer or an under-eater?Rapid weight gain may mean more fat depositionBulk up (lean mass) vs bulk out (fat mass)

Additional TipsFeature Add energy dense foods to the dietStack foods with add-onsPotato with toppingsDried fruit and nuts on cerealDont drink water right before mealsMonitor caffeine to promote rest

Content adapted from: Litt, A (2004) Fuel for Young Athletes

Adding energy dense foodsChoose ThisCaloriesOver ThisCaloriesCup of Granola500Cup of cheerios90Bag of Peanuts170Bag of pretzels110Sandwich on a subRoll500sandwich on bread300Bagel 330english muffin130Sports Drink 20 oz135water0Mistakes Commonly MadeThese

Over-eat proteinUnder-eat carbohydratesNo dietary variationSafe Weight LossBest Look at Common recommendation:1-2 pound per week decreaseLarger Greater number and volume of adipose cellsAre there bad foods?General rule of thumb: The less processed it is, the better nutritional benefits you will receive.Menu PlanningFueled Pre-exercise mealsGive ample time for digestionProvide the correct fuel matrixCHO, Minimize potential GI stressorsStress food safetyKnow their tastesKnow your budgetMenu PlanningEarly eventsTop Try AND light snack the morning of even (1-2 hrs. before)During ExerciseReplace fluid lossesExogenous Endurance: 30-60 g CHO/hr (common fuels used in endurance events: jellybeans, gels, energy bars, sports drinks)Begin intake shortly after activity begins80-90 g CHO/hr for ultra endurance (> 3 hours)Multiple transportable carbs

Position statement of the American diabetic association, dietitians of CanadaCommon CHO amounts32 ounces sports drink = 60 g4 fig cookies = 42 g Energy bar = 45 gBanana = 30 gCarb gel pack = 28 gHandful of pretzels = 25 gRecovery NutritionAfter exercise, Composition and timing of the recovery meal or snack depend on the length and intensity of the exercise session (ACSM, 2009).Glycogen Meals need to provide adequate fluids, electrolytes, carbohydrates, and protein.A carbohydrate .Recovery NutritionThe timing of .The type of food is also significant because consumption of high glycemic index CHOs results in .Protein consumed after exercise provides amino acids for building and repair of muscle tissue (ACSM, 2009).Recovery Nutrition SummaryReplace Can take 24 hours to fully reloadGlycogen replacement is spurred post exerciseTiming of meal less critical if 1-2 days rest are upcomingAs Sport Specific GuidelinesSoccer/Basketball/Hockey/Lacrosse/ect..High energy demandsCaloric Blood flow to the gut decreased (w/intensity)Higher CHO needs in-season/trainingRecovery critical with tournament playReplenish Prevents fatigue as season/training progresses

Dunford. M. (Ed). (2006) Sports Nutrition: A practice manual for professionalsSport Specific GuidelinesBaseballRelatively low energy demandsProne to weight gainSkipped meals due to schedulesIncreased Dehydration Sport Specific GuidelinesFootball:Energy needs High

Sport Specific GuidelinesEndurance Sp0rts:Uses the complete range of energy systemsFluid Primarily for the 2hr + eventsIf using CHO gels you need water tooSnack frequently on high carb foods day before racesSome Liberal sodium use, if neededPractice eating habits before put to race day use

Dunford. M. (Ed). (2006) Sports Nutrition: A practice manual for professionals

Sport Specific GuidelinesEndurance Sports:CHO loading guidelines:High You can One part glycogen to three parts stored waterProtein also catabolized for energy1.5 g/kg/day recommendation

Clark N. (2003). Nancy Clarks Sports Nutrition GuidelinesSport Specific GuidelinesSwimming:High volume training programs are commonAdjust intake to training season demandsFluid Organize Sports drinks, Multiple events = need recovery plan

Jeukendrup. A., (ed). (2010). Sports Nutrition: From lab to Kitchen, Meyer and Meyer SportSport Specific GuidelinesRecreational athletes Educate Recovery meal timing likely not as crucialEducate on caloric expenditure realitiesPrevents May require Fast food meal planning

Activity:Identify the best menu choice for recovery from the given menu for a 80 kg athleteRecap: Menu Planning Across a Spectrum of TrainingExamine Load up on the produceMinimum Maintain a good hydration planPractice new eating regimens before competing with themNutrition SupplementsSupplement is A nutrition supplement cannot replace a healthy dietWhy Supplement?Gain a perceived edgeImprove Change body compositionImprove performanceSupplement industry sales in 2011: Rate of growth of 7% annuallyDietary Supplement Health and Education ActPassed in 1994Product is a..VitaminMineralHerb or other botanicalAmino acidDietary substanceConcentrate or metabolite of any of the aboveHollonstein J (2007) Understanding Dietary Supplements134Structure and Function claims.StrengthenImproveProtectdefent2002 International Olympic Committee (IOC) Study94 From 12 different countriesU.S. supplements tested (45 of 240) had a 18.8% fail rateGreenwood M. Kalman D> Antonio J (eds) (2008) National Supplements in Sports and Exercise136Popular Sports Supplement ReviewBeta AlanineNon-essential amino acidServes Acts as a buffering agent for lactic acidSupplementation Marketed to enhance weight training and high intensity trainingPossibly effective more research needed on safetyReported

CaffeineStrongest CNS stimulantDecreased perception of effortIn moderate doses is NOT a diureticAmount Trial and errorApprox 2 cups of coffee

CaffeineGanio et al (2009) found that abstaining from caffeine at least 7 days before use will give the greatest chance of optimizing the ergogenic effectGliottoni et al (2009) Caffeine.not for everybody!monitor for side effects: Increased Nervousness GI problems If not a regular userHigh doses (>6 mg/kg) .Creatine:Found in Helps to replenish ATP reserves in the musclesProvides energy via phosphagen systemIncreases rate of phosphocreatine systhesisGenerally appears safe and effectiveSeems to ACSM recommends that it is NOT USED by children under the age of 18Hydration needs to be addressedPulls water into muscle cellsEnergy Drinks:Appeal to athletesNutrient profiles vary25 grams of Consumed Caffeine and the herbal stimulant amounts are a concern Stresses heart rate and can lead to heat illnessThe Color Code

RED Higher in saturated fat and caloriesUse in moderation these can slow you downYellow a moderate amount of fat and/or heavy processedGreen the leanest selections of protein and/or healthier a CHOHigh performance foodsCONCLUSIONThink about fuel and hydration as part of your internal equipment. You cant show up to practice and be strong, be quick, and last long without pre-fueling.Leslie Bonci, MPH, RD, CSSD, LDNPittsburg Steelers