MedNut - Sports Nutrition PPT + Handout + Side Notes (untoshible)

MEDICAL NUTRITION

SPORTS NUTRITION

Dr. maria Lourdes Corazon-fernandez-tapang 15 october 2014

CONTENT 1. Energy metabolism 2. Dietary requirements 3. Nutrition: before, during, and after exercise 4. Weight management 5. Dietary supplements and ergogenic aids

THE PHOSPHAGEN SYSTEM (ATP-CP SYSTEM)  Anaerobic  Adenosine Triphosphate and Creatine Phosphate provide readily available energy present within the muscle  The amount of ATP in skeletal muscles is approximately 5 mmol/kg wet weight and is not sufficient to provide continuous supply of energy  Creatine-phosphate is an ATP reserve in the muscle that can be readily converted to sustain activity for 3-5 min.  Creatine-phosphate in skeletal muscle is approximately 4x greater than ATP and is therefore the primary fuel for high intensity, short-duration activities  Used for events lasting no longer than a few seconds and of high intensity ― Diving ― 100 m dash ― Weight lifting ― Fast break in basketball ― Jumping

INTRODUCTION  Proper nutrition is a vital consideration for athletes who seek to maximize their performance  A proper diet will provide proper nutrients and energy for athletic performance, training and healing  Many factors affect nutrient needs and nutrient availability including the athletes’ ― Physical condition ― Nutrient status ― Age ― Genetic background  These factors make it essential that the diet be individualized SPORTS NUTRITION GOALS ARE TO ENSURE:  Adequate energy intake to meet the energy demands of training  Adequate replenishment of muscle and liver glycogen with dietary carbohydrates  Adequate protein intake for growth and repair of tissue, particularly muscle  Adequate overall diet to maintain a healthy immune system  Adequate hydration  Consumption of food and beverages to delay fatigue during training and competition  Minimization of dehydration during exercise ENERGY METABOLISM ENERGY STORAGE

TRANSFER

CHO, fat, protein supply energy, with fats and CHO being primary source energy is stored in the body in the of CP, CHO (blood glucose, liver, muscle, glycogen), fat (serum FFA and TG, muscle triglyceride, adipose tissue), protein (muscle) two metabolic systems to transfer stored energy to form ATP

ENERGY SYSTEMS ANAEROBIC SYSTEM  These system are capable of producing ATP energy at a high rate.  The main limitation of this system is the relatively small amount of ATP that can be made before fatigue ensues.

AEROBIC SYSTEM  It supplies all of the energy for low to moderate intensity exercise.  It supplies energy for sleeping, resting, sitting, walking and other forms of low intensity physical activity.

THE ANAEROBIC GLYCOLYTIC PATHWAY (EMDEN-MEYERHOFPARNAS OR GLYCOGEN-LACTIC ACID SYSTEM)  Uses muscle glycogen and glucose that are rapidly metabolized anaerobically through the glycolytic cascade  This pathway supports events lasting 60 to 180 seconds  Approximately 25% to 35% of total muscle glycogen stores are used during a single 30-second sprint or resistance exercise bout. ― 200-m dash

Anaerobic Metabolism  Phosphagen system  Glycolytic pathway Aerobic Metabolism  Oxidative pathway

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Neither the phosphagen nor the glycolytic pathway can sustain the rapid provision of energy to allow muscles to contract at a very high rate for events lasting greater than 2 to 3 minutes.

ENERGY INTAKE Food Fluids Supplements

THE OXIDATIVE PATHWAY  The major substrates include muscle and liver glycogen, intramuscular, blood, and adipose tissue triglycerides, and negligible amounts of amino acids from muscle, blood, liver, and the gut.  Can produce large amounts of ATP over time via the Kreb’s cycle and the electron transport system.  Fuels events lasting longer than 2-3 min.  Examples include ― 1,500-meter run ― Marathons ― Half-marathon ― endurance cycling or 500 meter swimming events.

ENERGY EXPENDITURE Basal Metabolic Rate Thermic Effect of Food Thermic Effect of Activity

Athletes need to consume adequate energy during periods of highintensity and/or long-duration training to: MAINTAIN

•Body weight and health

MAXIMIZE

•Training effect

LOW ENERGY INTAKES  Can result in: ― Loss of muscle mass ― Menstrual dysfunction ― Loss of or failure to gain bone density ― Increased risk of fatigue, injury, and illness ― Prolonged recovery process DIETARY REQUIREMENTS  

Athletes do not need a diet substantially different from that recommended in the Dietary Guidelines for Americans and Eating Well with Canada’s Food Guide Cautions is recommended in using specific proportions as a base for meal plans for athletes

Uses only glucose, anaerobic, high intensity activity 1-3 min, produces 2 ATP/glucose

Oxidative pathway

ATP-CP provides rapid energy, anaerobic, seconds, produces 0.7 ATP/PC

EMP pathway

Phosphagen system

BASIC NUTRIENTS  Nutrients are chemical substances in food that provide energy, act as building blocks in forming new body components, or assist in the functioning of various body processes CARBOHYDRATES  Carbohydrates is the optimal fuel for exercise  Yields approximately 4 kcals/gram  Carbohydrates are the basic source of energy for the body  In general, carbohydrates (CHO) should always provide at least 55% of total daily calorie (TDC) intake ideally 60-70% of TDC  At meals, carbohydrates should take up 2/3 of your plate  Foods containing carbohydrates: bread, rice, pasta, cereals, crackers, fruits, juices, vegetables, dried beans/peas, and grains  The body converts sugars and starches to glucose for energy or to glycogen for energy storage in the liver and muscles ― When glycogen stores are full, excess carbohydrates are converted to fat  While a high-carbohydrate diet is essential to good health in all individuals, it is especially important to the athlete  50-60% of the athlete’s caloric intake should be from carbohydrates to keep the glycogen stores filled  Carbohydrate loading (during pre-competition meals) is used to generate extra glycogen and requires a carbohydrate intake of 70-80%  Athlete recommendation is 5-10 g/kg/day or 2.7 to 4.5 g/lb/day ― Endurance – 5-10 g/kg/day ― Strength – 5-7 g/kg/day

uses CHO, fat, protein, aerobic, longer periods, produces 38 ATP/glucose

PROTEIN  Protein is critical to growth and development especially muscle and bones  General functions of protein ― Function as enzymes to catalyse chemical reactions in the body ― Many hormones are proteins ― Can be a source of energy  Yields approximately 4 kcals/gram  When carbohydrates and fats are not available (such as in starvation) and during prolonged endurance exercise  Used for building and repairing muscles, red blood cells, hair, and other tissues

The use of energy system over the other depends on:  duration of physical activity  intensity of physical activity  frequency of exercise  type of physical activity  fitness level of the individual  nutrient intake and energy stores ENERGY BALANCE  The objective of sports nutrition is to achieve energy balance, which is achieved when energy expenditure equals energy intake

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FAT   

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Used for energy when carbohydrates are not available Proteins are derived from animal foods – meat, milk, eggs, fish, cheese, and poultry. Also, from soybeans, dry beans, some nuts, and whole-grain products. As stated earlier, proteins may be used by the body for cellular energy, but proteins are the body’s least efficient source of energy. Recommended protein intakes can generally be met through diet alone, without the use of protein or amino acid supplements Extra protein not needed by the body, is burned for energy or stored as fat ― The body cannot store protein Protein intake should be approximately 10-12% of caloric intake The Dietary Reference Intake (DRI) for adults is 0.8 g/kg body weight Athlete recommendation is 1.2-1.7 g/kg or 0.5 to 0.8 g/lb/day ― Endurance athletes  1.2 – 1.4 g/kg (1.2-1.5 g/kg) ― Strength athletes  1.6 – 1.7 g/kg (1.5-1.7 g/kg)

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Source of energy, fat-soluble vitamins, and essential fatty acids Yields 9 kcals/g (over twice carbohydrates and proteins) General functions of fat ― They carry vitamins A and D to cells, and are necessary for normal growth and development ― Fats insulate the body ― They protect the body from the impact of injuries, and shield the body’s organs ― Add flavor to our food Helps sustain prolonged exercise Source of stored energy, burned mostly during low-level activity, and when other sources are not available Main sources include meats, eggs, milk, cheese, fried foods, butter, margarine, salad dressings, oils, and mayonnaise Healthier fat choices: nuts, seeds, olive oil, canola oil, fish, avocados, and olives Fats are necessary and important in our diet. Yet many people consider fats to be a harmful nutrient ― The problem is the fact that we often eat far more than the daily recommended amount of fats (30% of our caloric intake) High-fat diets are associated with heart disease, hypertension, and cancers Fats are not digested as quickly as other nutrients Fats are used when carbohydrate sources are depleted High-fat diets are not recommended for athletes Athele recommendation is 1.0-2.0 g/kg/day CHO CHON FAT

B Vitamins  Two major functions related to exercise: ― Involved in energy production  Thiamine, riboflavin, niacin, pyridoxine, pantothenic acid, and biotin ― Required for production of red blood cells, protein synthesis, and in tissue repair and maintenance including the CNS  Vitamin B12 and folate Vitamin D  For adequate calcium absorption and bone health  Regulates development and homeostasis of the nervous system and skeletal muscle  Athletes who train indoors  Recommended daily intake: ― 5 µg/day or 200 IU (19-49 y/o) Antioxidants: Vitamin C and E, β-carotene, and Selenium  Because exercise can increase oxygen consumption, it has been hypothesized that long-term exercise produces a constant oxidative stress on muscles and other cells  Habitual exercise however has been shown to result in an augmented antioxidant system  Should not exceed tolerable upper intake levels  Vitamin C is also needed for absorption of iron MINERALS: Calcium, Iron, and Phosphorus  Minerals do not provide energy!  Minerals are inorganic substances and are known to have functions essential to life  Calcium ― Bone health, bone strength, muscle contraction, nerve conduction, and normal blood clotting ― Athletes need 1200-1500 mg of calcium per day  One serving from the dairy group has about 300 mg calcium  Iron – one of the most prevalent nutrient deficiencies observed among athletes ― Oxygen carrying proteins, haemoglobin and myoglobin ― Enzymes involve in energy production ― Women need 15 mg and men need 10 mg of iron each day  Phosphorus ― For bone health ― Needed for strong bones and teeth  Sodium, Potassium, and Chloride ― Particularly for athletes who sweat profusely

5-10 g/kg/day or 2.7 to 4.5 g/lb/day 1.2-1.7 g/kg or 0.5 to 0.8 g/lb/day 1.0-2.0 g/kg/day

VITAMINS AND MINERALS  Vitamins do not provide energy!  Vitamins are essential for maintaining good health  Needed to regulate processes in the body ― Used to utilize energy from carbohydrates, protein, and fat  A lack of vitamins in the diet leads to deficiency conditions, which express themselves in a variety of ways  Most vitamins cannot be synthesized by the body and must be ingested via foods or pills  No single food or food group will supply all the vitamins needed by the body ― A good reason to eat a variety of different foods  Vitamins are usually identified as either fat soluble or water soluble

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― Fat soluble vitamins (vitamins A, D, E, and K) are emulsified and absorbed in the small intestines  These vitamins are stored in body cells. Especially liver cells ― Water soluble vitamins (B complex and vitamin C) are absorbed along with water through the digestive tract and dissolved in body fluids  The body doesn’t store these vitamins well and excess quantities are excreted in urine Vitamin requirements do not increase during exercise ― Available evidence does not justify supplementing the diet of the athlete with vitamins to improve physical performance unless a pre-existing vitamin deficiency exists ― Likewise, in athletes who do not choose nutrient dense foods, supplementation may be suggested Vitamins and minerals found to be of concern in athletes diets: ― Calcium ― Vitamin D ― B Vitamins ― Iron ― Zinc ― Magnesium ― Antioxidants such as Vitamin C, E, beta-carotene, and selenium

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― Sodium, potassium, and chloride are important for maintaining normal fluid balance in the body as well as in generation of muscle impulses ― Potassium – regulates cardiac rhythm ― Sodium loss in sweat outweighs potassium and chloride loss ― Loss of this electrolytes will cause cramping Exercise does not seem to affect dietary needs of most minerals with the exception of the effects of sweating ― Heavy sweating may lead to excess losses of sodium, chloride, and potassium ― Losses of these minerals may affect performance ― It is recommended that athletes involved in prolonged activity, especially those who are considered “salty sweaters” consume more salt in their meals before and after activity  Generally, this added salt can easily be gained through the salt added to foods and not through “salt pills”

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WATER  Water is often considered the most important nutrient ― Failure to consume other nutrients will show harmful effects on the body after several weeks or months but humans can only survive without water for a few days!  General function of water ― Provides an aqueous medium for chemical reactions to occur and for transportation of its products ― Provides a medium for transportation of oxygen, hormones, nutrients, etc. throughout the body (i.e. the blood) ― Facilitates thermoregulation for the body (i.e. sweat) ― Lubricates joints and cushions organs and tissues ― In saliva and gastric secretions, water helps digest food  Note that a loss of fluid through exercise may have an effect on these functions; many of which will affect performance  Dehydration – loss of >2% body weight  Compromise aerobic performance and may impair mental/cognitive performance – heat stress  We don’t rely on thirst mechanism but depends on a timely basis in rehydration (we hydrate even not thirsty)

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FLUID REPLACEMENT  Exercise increases water loss ― During normal breathing, water is added to inspired air to protect delicate respiratory cells from drying out  Increased breathing during exercise increase this loss ― Heat production is a byproduct of muscle contraction  Increased muscle contraction during exercise increases overall body heat forcing the body to compensate through sweating  Athletes may lose up to 1 liter per hour  Water loss affects performance ― Diminished water content in the blood causes:  Diminished capacity to transport oxygen and nutrients to body cells  Diminished capacity to get rid of excess heat from working muscles causing increased body temperature o Body cells must have a consistent temperature to function properly (homeostasis) ― Loss of fluid causes cells to shrink (crenation) which affects their normal function Hydration Protocol 2 hours before

2-3 cups

15 min before

1-2 cups

Every 15 min during

After activity

½ - 1 cup

At least 2 cups for each pound of body weight lose

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Monitoring hydration status  The body’s thirst mechanism lags behind dehydration ― By the time you are thirsty, you are already dehydrated ― Therefore, thirst is not a good indicator of hydration  There are a number of very expensive and time consuming test to monitor hydration but this process can be accomplished with relative ease ― Urine color is a good indicator of hydration  Diet, supplementation, or medications, may affect urine color ― Weight loss that occurs during a single bout of exercise is likely due to fluid loss  Changes in body weight can be used as a marker for short term fluid loss  One liter of water weighs approximately 1 kg (2.2 lbs) o If an athlete completes a hard workout lasting approximately one hour and loses 2 kg of body weight it can be assumed that approximately 2 liters of fluid have been lost o Or just simply drink until the pre-workout weight is reached

SPORTS DRINK  Help replenish lost sodium and glycogen stores ― During heavy sweating, water is not the only element lost

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― Electrolytes such as sodium, potassium, chloride, and traces of some others are also lost  Of these, sodium is lost in the greatest abundance During exercise of 2 hours or less the body is able to reabsorb sodium loss ― During exercise lasting less than two hours, the athlete would need to pay more attention to fluid replacement to address water loss through sweating than to sodium replacement ― Water works well as a fluid replacement beverage under these conditions During exercise lasting over 2 hours and in hot environments, sodium loss in sweat occurs too rapidly for reabsorption to occur and may also significantly decrease glycogen stores (stored glucose) ― Sports drinks may be a good option for fluid replacement during exercise lasting over 2 hours and for exercising in the heat  Sports drinks may help to replenish lost sodium and glycogen stores  Sodium replacement and maintaining hydration during exercise may help to reduce muscle cramping during exercise especially in salty and heavy sweaters o One cause of muscle cramping is an electrolyte imbalance caused from fluid and sodium loss from sweating o It should be noted that another cause of muscle cramping is muscle fatigue There are many types of sports drinks to choose from and choosing one over another is up to each individual ― However, there is a proper proportion of the chemicals in the drink in order to optimize performance and limit any detrimental effects Guidelines in choosing sports drink ― 6-8% carbohydrates is recommended  Less likely to induce gastric distress o Due to slowed gastric emptying in most individuals  Water absorption is maximized ― Sodium content of 460-690 mg/L  Replace loss  Encourage drinking o Since sodium tends to induce thirst Cold drink is preferable because it attenuates changes in core temperature and peripheral blood flow, decreases sweat rate, and speeds up gastric emptying time Example of a sports drink recipe ― 1 quart or 1 liter water ― 1/3 cup sugar ― ¼ teaspoon table salt ― Flavor to taste – use orange juice, lemon juice, etc. ― Keep refrigerated

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Fluid replacement strategies  Pre-hydration should begin at least 4 hours before competition ― Recommended is 5-7 mL/kg (5-10 mL/kg or 2-3 mL/lb)  Ex: a 50 kg (110 lb) female would drink 250-350 mL (8-12 oz or 1-1 ½ cups) ― This recommendation assumes the athlete is in a hydrated state at the time ― It should be noted that water is sufficient, however, sodium stimulates thirst and retention of body water so a beverage that contains sodium may be beneficial ― Pre-hydration should be determined on an individual basis and by trial and error to determine the appropriate amount for each individual  Too little may lead to dehydration during competition and therefore, decreased performance  Too much may leave the athlete feeling bloated and cause too frequent urine brakes that may interfere with pregame activities  Hydration during activity ― it is generally recommended that an athlete drink 6-12 oz of fluid every 15-20 minutes  Small amounts taken frequently are tolerated best by most athletes and leads to more effective gastric emptying  Hydration needs during activity is highly individual and routines should be established well before competition to avoid introducing a “new” routine during competition ― Cool beverages are tolerated best although studies do not show that temperature influences gastric emptying  Free access to water before, during, and after activity should be encouraged

Before Exercise At least 4 hours before  5-7 ml/kg body weight (2-3 ml/lb) 

During Exercise To avert dehydration  Dependent on sweat rate, exercise duration, and opportunities to drink  6-12 oz every 15-20 min. (not more than 1 cup) 

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Athletes should be encouraged to consume enough fluid to match fluid loss and prevent dehydration while not exceeding the amount of fluid lost ― Replacing sodium loss – 0.5 to 0.7 g/L NUTRITION BEFORE, DURING, AND AFTER EXERCISE PRE-EXERCISE OR PRE-GAME MEAL  Purpose: ― To help prevent hypoglycaemia  Symptoms: light-headedness, needless fatigue, blurred vision, and indecisiveness – all of which can interfere with performance ― To help settle the stomach absorb some of the gastric juices, and decrease hunger ― To fuel muscles, both with food eaten in advance that is stored as glycogen, and with food eaten within an hour ― To pacify the mind with the knowledge that the body is well fuelled Characteristics of a Pre-game Meal  Meal or snack should provide sufficient fluid to maintain hydration  ↓ fat and fiber to facilitate gastric emptying and minimize gastrointestinal distress  ↑ carbohydrate to maximize maintenance of blood glucose  Moderate in protein  Composed of familiar foods  Well tolerated by the athlete  Sports nutrition for performance benefits must begin day in advance ― Every day, eat adequate high-carbohydrate meals to fuel and refuel your muscles so they will be ready for action  Food eaten within an hour before exercise primarily decreases hunger and maintains blood sugar o It doesn’t significantly replenish muscle glycogen stores  When exercising for more than 1 hour (60-90 mins.), carbohydrates which slowly enter the bloodstream as they are digested (low glycemic index) such as rice, pasta, yoghut, oatmeal, bean soup, lentils, apples, or bananas are ideal ― When eaten an hour before exercise, these slow carbohydrates will be digested enough to be burned for fuel, and then will continue to provide sustained energy during long workout  When exercising for less than an hour, snacking on any triedand-tested foods that digest easily and settle comfortably is satisfactory. ― Bread, English muffins, bagels, crackers, and pasta are a few of the most popular high-carb, low-fat choices  Limit high-fat proteins like cheese, streak, hamburgers, and peanut butter ― they take longer to empty from the stomach because the fat delays gastric emptying ― may cause sluggishness and nausea  Be cautious with sugary foods (such as soft drinks, jelly beans, and even lots of maple syrup or sports drinks) or carbohydrates that quickly enter the bloodstream as they are digested (potato, honey, or corn flakes) – postprandial hypoglycaemia ― Many athletes who eat these foods within 15-120 minutes before hard exercise can experience a drop in blood sugar that leaves them feeling tired, light-headed, and needlessly fatigued ― Experiment and learn how your body responds  Allow adequate time for food to digest ― Remember that high calorie meals take longer to leave the stomach than do lighter snacks ― The general rule of thumb is to allow at least 3-4 hours for a large meal to digest, 2-3 hours for a smaller meal, 12 hours for a blended or liquid meal, and less than an hour for a small snack, according to your own tolerance ― Some athletes can comfortable eat before they exercise, but others prefer to abstain. Both sports perform well, and both have simply learned how to best fuel their bodies

After Exercise Recovery from dehydration 16-24 oz (450675 ml) of fluid for every pound of body weight lost

HYPONATREMIA  A potentially serious medical complication that may occur in endurance athletes during prolonged exercise such as ultramarathons or triathlons ― Events lasting 4 hours or more and is more common in heat and high humidity  Occurs when plasma sodium concentration falls below normal (130 mEq/L)  Sodium plays a vital role in maintaining normal fluid balance throughout the body ― Low sodium level in the extracellular compartment causes fluid to move into cells causing them to swell ― This is particularly important in nerve cells which require sodium in proper proportions in order for nerve conduction to occur  Causes: ― Excessive sodium loss due to heavy sweating ― Overconsumption of hypotonic fluids (water)  Signs and symptoms: ― Dizziness, confusion, lethargy, seizure, loss of consciousness or coma, and death  Prevention: for events lasting over 3 hours replace sodium loss through use of fluids containing sodium or eating salty foods ― Matching amount of sweat lost

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― It should be noted that exercise increases blood flow to working muscles and away from digestive organs  This can cause stomach irritation if a large meal is eaten just prior to exercise Always eat familiar foods before a completion ― Don’t try anything new! ― New foods always carry the risk of settling poorly; causing intestinal discomfort, acid stomach, heartburn, or cramps Drink plenty of fluids

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Carbohydrate Loading  The purpose of carbohydrates loading is to “supercompensate” for glycogen depletion in an effort to store the maximum amount of glycogen possible prior to an event  Athletes who may benefit from the strategy: ― Endurance athletes whose events last for more than 90 minutes  Examples: long-distance runners, swimmers, bicyclists, and cross-country skiers ― Athletes involved in sports that require prolonged movement of varying intensities  Examples: soccer, lacrosse, and ice hockey ― Athletes who participate in tournament sports such as tennis  The most accepted protocol is a 6 day cycle ― Phase 1 – “depletion phase”  The athlete participates in 3 days of high intensity training to deplete glycogen stores o The first day should be 90 minutes of intense training o Followed by 2 days of 40 minutes of intense training  Carbohydrate intake during this phase should be 5 g/kg/day – the minimum amount recommended to athletes in training ― Phase 2 – “repletion phase”  Intensity of training is tapered over the next 3 days  Carbohydrate intake increases to 10 g/kg/day  This is followed by 1 day of rest  Some side effects may occur ― During, carbo-loading, the athlete’s weight should increase by 1-3 pounds, since water is stored with glycogen  This may not be tolerated well by some athletes who may feel sluggish and heavy ― Eating too many carbohydrates can lead to intestinal distress  Choose wholesome, fiber-rich carbohydrates ― to keep your system running smoothly ― pasta, rice, bran muffins, whole wheat bread, cran cereals, fruits, and vegetables are good choices

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DURING EXERCISE  Important for endurance events lasting longer than an hour when an athlete has not consumed adequate food or fluid before exercise, or if an athlete is exercising in an extreme environment (e.g. heat, cold, or high altitude)  Rationale: ― replace fluid losses ― provide carbohydrates for maintenance of blood glucose levels ― provide needed sodium lost during heavy sweating  Recommended intake: ― Events lasting more than one hour or less: 6-8% CHO in sports drink ― Events longer than one hour: 0.7g CHO/kg body weight/hr or 30 to 60 g per hour ― Sodium: 0.5 – 0.7 g/L of fluid lost ― Fluid as much as sweat rate or approximately 1 cup every 15-20 min.

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POST-EXERCISE/RECOVERY MEAL  What you eat after a hard workout or competition does affect your recovery  Foods eaten after exercise or competition require the same careful selections as the meal before exercise THIS TRANS IS MADE FOR FREE. DON’T USE THIS FOR BUSINESS PURPOSES. PLEASE. IF YOU WANT TO SELL NOTES, MAKE YOUR OWN.

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Competitive athletes who are engaged in2 or more workouts per day must be especially concerned about recovery diet such as: ― Football player at training camp ― Competitive swimmers who compete in multiple events per meet ― Triathletes who train twice per day ― Aerobics instructors who teaches several classes daily ― Basketball players who needs to endure the entire season of intense training and competing Athletes commonly have reasons to eat inadequately after exercise, including that they don’t feel hungry and don’t have time Provide adequate fluids, electrolytes, energy, and carbohydrates ― Replace muscle glycogen and ensure rapid recovery RECOVERY CARBOHYDRATE: ― 1.0 to 1.5 g/kg (0.5-0.7 g/lb) body weight  (0.75-1.5 g/kg body weight in the handout)  Ex: a 176 lb athletes should consume approximately 120 g of carbohydrates o This could easily be achieved with a banana, 10 oz of sports drink, and a bagel o Consumption of carbohydrates in smaller, more frequent meals appears to further aid the rate at which muscle glycogen is replaced in the hours after exercise - With larger meals, blood glucose and insulin rise rapidly and then return to baseline relatively quickly - Blood glucose levels can be sustained for a longer period of time with smaller meals ― Ideally, carbohydrate-rich foods and beverages should be consumed within 1st 30 minutes (15-30 minutes in the handout) after a workout and again every 2 hours for 4 to 6 hours  This is when the enzymes responsible for making glycogen are most active and will mostly rapidly replace the depleted glycogen stores ― Liquids and solid foods will refuel muscles equally well ― Glucose rather than fructose is the preferred substrate  Studies show fructose does not result in glycogen synthesis rates that are as high as those with glucose ― Solid foods should have a high glycemic index (causes a rapid rise in blood glucose levels)  These are most effective in enhancing the resynthesis of glycogen  Ex: white bread, corn flakes, baked potatoes, white rice, pancakes, bagels  Many “energy bards” have a high glycemic index RECOVERY PROTEIN: ― Protein intake after exercise is important for muscle anabolism  Provide amino acids for building and repair of muscle tissue ― 6 g immediately after exercise (0.1 g/kg body weight) ― Good examples of proteins are:  Yogurt with fruit in the bottom  Chocolate milk  Turkey sandwich ― Some protein can actually enhance glycogen replacement in the initial hours after hard exercise ― Protein eaten along with carbohydrates is recommended RECOVERY ELECTROLYTES ― Sweating not only causes water loss but also some minerals (electrolytes) such as potassium and sodium that help the body function normally ― Electrolytes losses are primarily responsible for muscle cramping and intolerance to heat ― Most athletes should be able to consume more than enough electrolytes from standard post-exercise foods  Salt tablets or special supplements are rarely needed

WEIGHT MANAGEMENT

o May underestimate body fat by 2-3% Dual X-ray Absorptiometry (DXA) o Originally developed to assess bone mineral o Fairly accurate, quick and non-invasive o Cost and accessibility limits its use in practice ― LEVEL III – DOUBLY INDIRECT ASSESSMENT  Skinfold Calipers o Makes use of large “pinchers” that measure thickness of the fat layer on specific body sites – abdomen, biceps, triceps, subscapula, supraspinale, medial calf, and front thigh o Method of choice because of its convenience and because its relatively inexpensive  Bioelectrical impedance analysis (BIA) o An imperceptible electrical current is sent through the body which flows up one leg and down the other o Based on the principle that an electrical signal is more easily conducted through lean tissue than fat or bone o Fat mass is estimated by subtracting the BIAdetermined estimate of FFM from total body mass o Hydration status affects result All methods for body fat measurement have potential errors 

BODY COMPOSITION  Refers to all of the components that make up the body  Divided into 2 main categories: ― Fat mass ― Fat-free or lean body mass  Includes muscle, bone, fluids, and organs ― Most athletes are interested in the ratio of fat mass to total body mass which is commonly expressed as percent body fat  Essential fat is the minimum amount of fat necessary for proper physiological function

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Description Essential fat Athletes Fitness Average Obese

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Women 10-13 % 14-18 % 19-23 % 24-29 % 36 %

Men 2-5 % 6-11 % 12-16% 17-23 % 29+ %

― Essential fat for males = 3% of body weight ― Essential fat for females = 12% of body weight  Of this 12% approximately 9% is considered sexspecific fat o this is fat needed for proper hormonal and reproductive functions ― Body composition that drops below these levels interferes with normal body function Body Fat norms are as follows Females Males 29

WEIGHT GAIN STRATEGIES  Weight gain should be achieved through a gradual increase in energy intake  Theoretically, in order to gain 1 pound of body weight per week, the consumption of an additional 500 calories per day is needed ― The extra calories should primarily come from extra carbohydrates  Carbohydrates fuel muscle so the muscles can perform intense muscle-building exercise ― Energy coming from fat should not exceed more than 30%  Increased protein intake is likewise recommended ― Daily increase of 14 grams per day ― To provide necessary amino acids for muscle growth  To date, research indicates that protein powders and amino acid supplements are a fruitless expense when it comes to gaining muscle weight ― The only reason some athletes may see results from these is likely due to the additional calories  Weight is most likely gained if larger-than-normal meals are consumed  Finding the time to eat can be the biggest challenge to boosting caloric intake ― Pack portable snacks ― Eat frequently throughout the day ― Eat larger than normal portions at mealtime ― Eat higher calorie foods  Taking the prescribed 500-1000 additional calories per day should cause some weight gain ― It is vital to include muscle-building resistance exercise (weight workouts) to promote muscular growth rather than just fat deposits

Three levels of assessment techniques are used to assess body composition: ― LEVEL I – DIRECT ASSESSMENT  Based on analysis of cadavers  Not used in clinical practice ― LEVEL II – INDIRECT ASSESSMENTS  Hydrostatic (underwater: weighing) o Traditionally considered as the most accurate method o The subject exhales and is weighed while submerged in a tank of water o Measures body density which is then translated mathematically into percent body fat  Plethysmography (Bod Pod) o Measures displacement of air to determine body volume o Once body volume is determined, body density can be calculated and body fat estimated o The subject sits in an air-tight enclosure while amount of air displaced is sensed by a special diaphragm and pressure transducer

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― It is recommended to have body fat routinely measured, to be sure that weight gain is mostly muscle, not fat  WEIGHT LOSS STRATEGIES  Understanding body composition is an important component of weight loss ― Muscle weighs more than fat  When an individual begins an exercise program in an effort to lose weight he or she may find that the scale is not showing significant weight loss – however, it is likely that body composition is changing (fat may be decreasing while muscle is increasing) ― For this reason some form of body composition analysis should be utilized rather that body weight itself  Body fat is stored energy ― In order to decrease body fat, one must burn more calories that he or she eats which forces the body to use these energy stores (fat) – eat less and exercise more ― It should be noted that every human body is different and fat is stored at different rates for each person  Storing fat can be affected by genetics, health, etc  Theoretically, 1 lb per week should be lost if 500 fewer calories per day is eaten ― It is recommended that only 1-2 pounds per week be lost for safety reasons  To lost weight healthfully, and successfully keep it off pay attention to dietary habits ― Pay attention to the quantity of food eaten ― Pay attention to when food is eaten (eat big breakfasts, rather than big dinners) ― Pay attention to why food is eaten  i.e. boredom, stress loneliness, or actually hungry ― Studies show that eating 5-6 small meals per day is an effective method to loose body fat  Eat slowly – the brain needs about 20 minutes to receive the signal that food has been eaten ― No matter how much food is consumed during those 20 minutes, the satiety signal doesn’t move any faster  Exercise regularly but not overdo it ― Moderate intensity – can be sustained longer and to ensure fats are mobilized and not carbohydrates ― Too much exercise may lead to injury, fatigue, and irritability ― Exercise will be more satisfying when it is for fun and fitness, not for simply burning off calories  Crash diets never work ― Weight loss fads are common in today’s world ― These technique usually focus on restriction of calorie intake and usually have an individual eating foods that vary from their usual choices ― Such diets are unsuccessful because losing body fat and keeping it off requires a behaviour change that can continue throughout the person’s life! ― These diets can actually cause long term weight gain because caloric restriction causes the body to slow its metabolism in an effort to save the calories that are available  This means that the body will burn less calories day to day than normal ― These fads are dangerous and can cause problems such as hair loss, weakened immune system, pH imbalances, and sudden death  Weight loss should be done only during off season

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ERGOGENIC AIDS  

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Any substance (or food) that is believed to enhance one’s performance above normal standards. The IOC definition: “The administration or use of substances in any form alien to the body or of physiological substances in abnormal amounts and with abnormal methods by health persons with the exclusive aim of attaining an artificial and unfair increase in performance in sports.” The use of these substances and practices is controversial. There is great concern about the number of athletes engaging in the use of ergogenic aids. ― Drug testing has been instituted in many sporting programs in order to help curtail the use of these substances Because of ethical violations associated that can result, use of these substances cannot be condoned!

COMMON ERGOGENIC AIDS Ergogenic aids that perform as claimed Ergogenic aid Creatine

Caffeine

RAPID WEIGHT LOSS IN SPORTS  Some sports dictate that athletes make changes in body weight and composition that may not be best for the individual athlete ― Sports that have weight categories because differences in body size make it impossible for all athletes to fairly compete among one another  Examples include wrestling, boxing, martial arts, and lightweight rowing ― Body-conscious sports where physical appearance may be judged

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Examples include gymnastics, figure skating, horse racing, and cheerleading With extreme energy restrictions, losses of both muscle and fat mass may adversely influence an athlete’s performance Weight loss tactics include calorie restrictions, excessive exercise, fluid restriction, or a combination (exercising in rubber suits, spitting in a cup, etc) These tactics have serious risks and should never be condoned ― Most health risks are associated with prolonged energy deprivation or dehydration ― There are several documented cases of deaths due to these tactics ― Other side effects include frequent nose bleeds, headache, dizziness, nausea, etc ― Studies are also showing that the weight “cycling” of these athletes is leading to lowered metabolic rate as aging occurs and an increase likelihood of being overweight later on in life ― Many states are implementing rules to limit such tactics in order to create a safer environment for the athletes  In 2006 the National Federation of State High School Associations instituted rule changes that include: o A body fat assessment no lower than 7% in males and 12% in females o A monitored weight-loss program that does not exceed 1.5% loss of body weight per week o A specific gravity of urine not to exceed 1.025

Sodium Bicarbonate

Protein and Amino Acid Supplements

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Pros* Widely used. Build muscle and enhance recovery. Effective in high intensity activity in sports. Not for endurance sports such as distance running. Central nervous system stimulant.

Cons The effects of longterm use of creatine remain unknown.

Remarks Screening of liver or kidney dysfunction.

Diuretic. Anxiety. Rapid heartbeat. Gastrointestinal distress Diarrhea.

Athlete should drink a lot of fluid.

Effective as a blood buffer (role in acidbase balance and prevention of fatigue). Protein and amino acid supplements are no more or no less effective than food when energy is adequate for gaining lean body mass.

Creatinine  The most widely used ergogenic aid among athletes wanting to build muscle and enhance recovery  Shown to be effective in repeated short bursts of highintensity activity in sports that derive energy primarily from the ATP-CP energy system  Adverse effects: cramping, weight gain, nausea, and diarrhea Caffeine  Ergogenic effects may be closely related to its role as a CNS stimulant and the decreased perception of effort  Still a restrictive substance by the NCAA ― Positive doping test would be caffeine level >15 µg/mL of urine  Adverse effects: anxiety, jitteriness, rapid heartbeat, GI distress, and insomnia Sports drinks, gels, and bars  Used as convenient dietary supplements or ergogenic aids for busy athletes and active people Sodium bicarbonate  May be an effective ergogenic aid as a blood buffer (acid-base balance and prevention of fatigue)  Side effect: diarrhea Protein and amino acid supplements  Current evidence indicates that protein and amino acid supplements are no more or no less effective than food when energy is adequate for gaining lean body mass  Potential source of illegal substances such as nandrolone Ergogenic aids that may perform as claimed but for which there is insufficient evidence  Glutamine ― Boosts immunity and for muscle building  β-hydroxymethylbutyrate ― Anticatabolic enhances recovery by stimulating protein and glycogen synthesis  Colostrum  Ribose Ergogenic aids that do not perform as claimed  Majority of ergogenic aids currently in the market fall in this category  Examples: ― amino acids ― bee pollen ― branched chain amino acids ― carnitine ― chromium picolinate ― cordyceps ― coenzyme Q10 ― conjugated linoleic acid ― cytochrome C ― dihydroxyacetone ― γ-oryzanol ― ginseng ― inosine ― medium-chain triglycerides ― pyruvate ― oxygenated water ― vanadium

Source: Dra. Tapang’s PPT, lecture and handout

Ergogenic aid that are dangerous, banned, or illegal  Banned by WADA  Examples: ― androstenedione ― dehydroepiandrostrone ― 19-norandrostenedione ― 19-norandrostenediol ― androgenic steroids ― Tribulus terrestris ― ephedra ― strychnine ― human growth hormone THIS TRANS IS MADE FOR FREE. DON’T USE THIS FOR BUSINESS PURPOSES. PLEASE. IF YOU WANT TO SELL NOTES, MAKE YOUR OWN.

こんにちは私の愛 HELLO milove. ;)

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