Nutrition Final review part 1

CH 7: Vitamin-like Compounds: Choline

D R I: •A I = 550 mg/day males; 425 mg/day females. •U L = 3.5 grams/day. Food Sources: •Animal foods as lecithin; plants as free choline. •Milk, liver, and eggs are good animal sources. •Good plant sources include vegetables, legumes, nuts, seeds, and wheat germ. Functions: •Precursor for lecithin, a phospholipid in cell membranes. •Involved in the formation of acetylcholine, an important neurotransmitter.

CH 7: Biotin

D R I: •AI = 30 mcg. •No UL has been established. Food sources: •Organ meats, egg yolk, legumes, green leafy vegetables. •Also synthesized in the intestines by bacteria. Major functions: •Coenzyme for enzymes involved in CO2 transfer. •Important in synthesis of glucose and fatty acids. •Involved in gluconeogenesis.

CH 7: Pantothenic Acid

D R I: •AI = 5 mg. •No UL has been established. Food sources: •Distributed widely in all natural animal and plant foods. •Organ meats, eggs, legumes, yeast, whole grains, fortified cereals, and mushrooms. Functions: •An essential component of coenzyme A which plays a role in the metabolism of carbohydrate, fat, and protein. •Involved in gluconeogenesis, synthesis and breakdown of fatty acids, modification of proteins, and synthesis of acetylcholine.

CH 9: What is hyponatremia and what causes it during exercise?

Decrease in plasma sodium (Na+ <135mmol/L) •Mild (<130 mmol/L). •Severe (<120 mmol/L). Hyponatremia associated with prolonged endurance exercise tasks is known as Exercise-Associated Hyponatremia (E A H).

CH 7: Biotin Deficiency

Deficiencies are rare, but may occur in diets rich in raw egg whites. •Cooking eggs eliminates the problem. Symptoms may include: •Loss of appetite, •Mental depression. •Dermatitis. •Muscle pain. No studies relative to deficiency states in athletes.

CH 7: Pantothenic Acid Deficiency

Deficiencies are very rare. Symptoms would include: •Fatigue. •Muscle cramping. •Headache. •Impaired motor coordination. Effects on physical performance have not been studies.

CH 7: Folate Deficiency—Health Effects

Deficiencies may occur during times of rapid growth. May impair D N A formation or lead to an increase in homocysteine. •Can damage lining of blood levels and initiate plaque, increasing the risk for C H D, stroke, peripheral vascular disease, and Alzheimer's disease. May increase risk of cancer due to D N A and chromosomal damage. •Colon cancer. •For women who consume alcohol, those with the lowest dietary folic acid intake are at the highest risk of breast cancer. Increased risk of neural tube defects.

CH 8: Selenium Deficiency

Deficiency is rare in industrialized countries. Keshan disease in areas of China with low soil selenium. Hypothesized relationship to various diseases: •Cancer, heart disease, type 2 diabetes. •Cognitive decline in aging. •Impaired thyroid gland function. However, as noted, deficiency is rare. For the athlete, theorized to impair antioxidant functions, leading to muscle tissue or mitochondrial damage, though not supported by data.

CH 8: Iron Regulation in the Body

Deficiency or excess may lead to serious health problems. Hepcidin—regulatory hormone produced by the liver. •More produced with elevated serum iron levels. •Less produces with depressed serum iron levels. Hepcidin helps regulate body iron stores. •Elevated hepcidin will inhibit iron absorption. •Low levels of hepcidin will increase iron absorption.

CH 8: Phosphorus Deficiency

Deficiency: Effect on Health. •Deficiency states are rare: bone loss could occur in such cases, resulting in rickets or osteomalacia. Deficiency: Effect on physical performance: •Has not been studied. •Muscle weakness, poor appetite, fatigue, and weight loss may occur.

CH 8: Copper Deficiency

Deficiency: Effects on health. •Rare; Menkes syndrome may impair copper metabolism. •Major deficiency symptom is anemia. •Osteoporosis, neurological defects, and heart disease may also develop. Deficiency: Effects on sport performance. •Rare; no research indicates athletes experience problems with copper deficiency.

CH 7: Choline Deficiency

Deficiency: Health Effects: •Deficiency is very rare. •Experimental deficiency: Fatty liver and liver damage. Deficiency: Physical Performance. •Plasma levels reduced in marathon; no adverse effects noted.

CH 7: Riboflavin Deficiency

Deficiency: Health Effects: •Glossitis (inflammation of the tongue), skin cracks, and scaly skin. •Confusion and headaches. Deficiency: Physical Performance: •Has not been studied directly. •Athletes may need more than the R D A during training. Deficiencies are rare: •Seen in alcoholics and those adhering to various fad diets.

CH 7: Niacin Deficiency

Deficiency: Health Effects: •Loss of appetite, skin rashes, mental confusion, lack of energy, muscle weakness. •Pellagra: severe dermatitis, diarrhea, dementia. Deficiency: Physical Performance. •Could impair aerobic and anaerobic endurance performance, but no research involving niacin alone has been conducted.

CH 7: Vitamin K Deficiency

Deficiency: Health Effects: •Uncommon, but may occur with very low-vitamin K diets and if antibiotics destroy intestinal bacteria that make it. •May cause impaired blood clotting; lead to hemorrhage. •Associated with osteoporotic bone fractures. Deficiency: Physical Performance. •No data available.

CH 7: Vitamin E Deficiency

Deficiency—Health Effects (rare): •May result from a genetic inability to absorb fat or from very low fat diets. •Anemia may occur because membranes of red blood cells are oxidized and release their hemoglobin. •Symptoms noted in animals include nutritional muscular dystrophy and damage to the heart and blood vessels. •May contribute to development of heart disease and cancer. •May lead to premature aging and decreased fertility. Deficiency—Physical Performance: •May lead to impaired oxygen transport which would reduce VO2 max and decrease aerobic endurance capacity.

CH 7: Thiamin Deficiency

Deficiency—Health Effects: •Loss of appetite, mental confusion, muscular weakness, and pain in the calf muscles may occur in 1 to 3 weeks. •Beriberi if prolonged: damage to nervous system and heart. Deficiency—Physical Performance: •Thiamin needs are increased with exercise and a high-carbohydrate diet. •Deficiency impairs endurance performance. Deficiencies are rare: •Most common in alcoholics and those consuming inadequate kcal.

CH 7: Vitamin A (2)

Deficiency—effects on health: •Night blindness; increased susceptibility to infections and skin lesions; deficient intake of beta-carotene may lead to several kinds of cancer; blindness from xerophthalmia (destruction of cornea). Deficiency—effects on sport performance: •Theoretical problems with impaired gluconeogenesis, synthesis of muscle protein, or vision in sports, but little research is available to support these contentions.

CH 7: Vitamin D Supplementation—Health Effects (2)

Diabetes: •May enhance immune functions to prevent autoimmune diseases. •Supplementation suggested to help prevent type I diabetes in children. Kidney stones and other adverse effects: •Excess calcium may combine with some salts, such as oxalates, to form kidney stones. •Excess calcium may lead to calcified plaque in arteries. •Excess vitamin D may cause vomiting, diarrhea, weight loss, and loss of muscle tone.

CH 8: Diet and Exercise and Calcium Deficiency

Diet. •Inadequate intake is major cause of deficiency; average intake in the United States is 868 mg/day for adult females and 1,116 mg/day for adult males. Other dietary and sport/exercise factors: •Lactose intolerance or cow's milk allergy. •Vegetarians who consume no dairy products. •Eating disorders like anorexia. •Heavy sweat losses of calcium.

CH 8: Iron

Dietary Reference Intakes (D R I): •R D A = 8 mg/day for men and postmenopausal women; 18 mg/day for females ages 19 to 50, and 27 mg/day for pregnant women. UL = 40 to 45 mg. Food sources: Heme iron and nonheme iron.

CH 7: Vitamin E Prudent Recommendations

Diets rich in vitamin E may be beneficial. Supplements taken for purported health benefits should be used with caution. •May increase a person's risk for hemorrhagic stroke. Supplements not recommended as a means to enhance physical performance.

CH 9: How does environmental heat affect physical performance?

Distance running performance impaired. •Significant linear relationship between W B G T and decreased performance in 10-kilometer run. Marathon running performance. •Running times decrease about 1 minute for every 1°C ↑ beyond 8 to 15 C (each 1.8°F beyond 46 to 59° F). Average 15% decline in cycling power output with wind speed and acclimatization exerting significant modulating influences on the degree of performance impairment.

CH 9: A C S M Fluid Intake Guidelines: During Competition 2

Drink fluids with carbohydrates for longer-duration events. •Select a C E S with a 6 to 8 percent concentration. •Use a C E S containing multiple sources of carbohydrate, including glucose, sucrose, fructose, and maltodextrins. •Consume enough fluid to provide about 30 to 80 grams of carbohydrate per hour. •One ounce of a C E S provides about 2 grams of carbohydrate. •Use sports gels or sports beans to provide additional carbohydrate if the necessary fluid intake would be unreasonable. •Sports gels and beans may provide about 25 to 30 grams of carbohydrate per serving. Drink fluids with small amounts of electrolytes, particularly sodium and potassium. •Many C E S contain about 20 to 30 mEq of sodium and 2 to 5 mEq of potassium, which amounts to about 110 to 160 grams of sodium and 19 to 45 grams of potassium in an 8-ounce serving.

CH 9: A C S M Fluid Intake Guidelines: Before Competition and Practice 2

Drink water. •However, carbohydrate-electrolyte solutions (C E S) also may be used if preferred. Drink beverages with carbohydrate (6 to 8 percent) to help increase body stores of glucose and glycogen for use in prolonged exercise bouts. Drink beverages with sodium (20 to 50 mEq/l) and/or consume salty foods or snacks to help increase body stores of sodium and water for prolonged exercise. Do not drink excessively, which may increase the risk of dilutional hyponatremia if fluids are aggressively replaced during and after exercise.

CH 9: Body Heat Dissipation during Exercise

During exercise in a cold or cool environment, body heat is lost mainly through radiation and convection via the air movement around the body. During exercise in a warm environment: •Sweat must evaporate to lose body heat. •Maximal evaporation rate is about 30 ml/minute. •Evaporation of 1 liter of sweat = 580 kcal of heat . •Sweat that drips off does not remove heat. •Sweat rates vary among individuals.

CH 8: Prudent Recommendations for Selenium

Eat a well-balanced diet with plenty of grain products. Supplements do not appear to enhance exercise training or performance. Do not take supplements that contain more than 200 mcg. •Toxicity symptoms include nausea, diarrhea, fatigue, brittle fingernails, loss of hair and nails, garlicky body odor, and peripheral neuropathy.

CH 8: Phosphorus Supplementation

Effect on health: •Not studied, since deficiencies are rare. Effect on physical performance: •In W W I, phosphate supplementation was reported to relieve fatigue, though much of this early research was discredited. •Phosphate loading may increase 2,3-B P G and related oxygen dynamics during aerobic endurance exercise. •Results of ergogenic effects are inconsistent.

CH 7: Folate Supplementation—Health Effects

Effective at preventing neural tube defects. May reduce risk of stroke and cardiovascular disease. Large doses of folic acid may mask a vitamin B12 deficiency. •Pernicious anemia will not develop, but damage to the myelin sheath will continue and may not be recognized until irreparable damage is done. May increase the risk of some forms of cancer.

CH 8: Magnesium Deficiency (2)

Effects of exercise on Mg levels: •Many athletes, especially in weight-control sports, may not obtain the R D A for magnesium. •Plasma Mg levels decrease following exercise. •Some Mg may be lost in sweat and urine. Deficiency theorized to: •Impair performance. •May contribute to overtraining syndrome.

CH 9: How do dehydration and hypohydration affect physical performance?

Effects of hypohydration. •Decrease in both intracellular and extracellular fluid volume, particularly blood volume. •Decreased stroke volume. •Decreased cardiac output. •Body heat storage increases. •Decreased sweating rate. •Decreased skin blood flow responses. •Earlier onset of lactate threshold. •Electrolyte imbalances.

CH 8: Copper Supplementation

Effects on health: •No beneficial effects. •May be used in some eye supplements, but mainly to help prevent adverse effects of high zinc content. •Excess, even 5 to 10 mg daily, may cause nausea and vomiting. Recent research suggests excess copper, mainly from water pipes, may be involved in a diet-gene interaction with Wilson's disease, and be involved with the increased incidence of Alzheimer's disease. Prudent recommendations: •Consume a balanced diet. •Supplementation not recommended.

CH 7: Thiamin Supplementation

Effects on health: •No benefits to well nourished individuals. •No UL has been established for thiamin. Effects on exercise performance: •No beneficial effects on performance. Prudent recommendations: •Supplements are not needed by the individual who is consuming an adequate diet. •Supplements do not appear to enhance exercise performance.

CH 9: Involuntary Dehydration 2

Effects on mental/cognitive performance. •May impair vigilance in dynamic sports environments, such as basketball & soccer. •Progressive deterioration in basketball skills with increasing levels of dehydration from 1 to 4%. Effects on gastrointestinal distress. •Nausea, vomiting, bloating, G I cramps, flatulence, diarrhea, G I bleeding.

CH 9: Factors that Influence Sweat Rate

Environment: •Air temperature. •Relative humidity. •Radiant heat (solar and ground). •Wind. •Clothing worn. Individual characteristics: •Body weight. •Genetic predisposition. •Metabolic efficiency. •Heat acclimatization state. •Wide individual variability.

CH 7: Can the antioxidant vitamins prevent fatigue or muscle damage during training?

Equivocal research and review findings relative to the effects of antioxidant supplementation. •Some studies show reduction in markers of muscle tissue damage. •Other studies show no benefits. •Several studies found adverse effects of supplements. •Some suggest older athletes may benefit. Most researchers agree: •More studies are needed. •Athletes should obtain antioxidants from natural foods.

CH 9: How is high blood pressure treated?

Essential hypertension is incurable. Drugs to control hypertension. •Diuretics (may impair exercise performance). •Beta-blockers (may impair exercise performance). •Calcium channel blockers. •Angiotensin-converting enzyme (A C E) inhibitors. Use nonpharmacologic approach first. •Lifestyle modifications.

CH 8: Are mineral megadoses or some nonessential minerals harmful?

Excess amounts of minerals normally do not occur from diets of natural, wholesome foods. Consuming mineral supplements along with fortified foods can lead to excess mineral intake. All trace minerals appear to be toxic if consumed in excess over a long period of time. Nonessential minerals may impair health: •Lead. •Hexavalent chromium. •Mercury found in fish.

CH 9: Heat Stroke 1

Exertional heat stroke. Caused by interaction of various factors: •High temperature and/or humidity. •Strenuous exercise. •Dehydration . •Inadequate heat acclimatization. •Lack of fitness. •Obesity. •Clothing that limits evaporation of sweat. •Genetic factors. •Medications. •Fever. •Sleep deprivation.

CH 9: Heat Syncope

Fainting. Also known as exercise-associated collapse Caused by excessive vasodilation and decreased relative blood volume. •Venous return decreases and cardiac output then decreases. •Blood flow to brain is decreased. Prevention. •Cool down after exercise; maintain venous return from legs. •If dizzy, lie down with feet elevated.

CH 8: Prudent Recommendations for Iron

Females, adolescents, and athletes in heavy training should focus on dietary iron intake. •Screening at the beginning of and during the training season are often advised. Iron supplements may be recommended for some athletes. •Female distance runners, some vegetarian athletes, those with heavy menstrual blood flow, those who initiate high altitude training, and those with restricted calorie intake. Do not take iron supplements indiscriminately. Some health professionals recommend iron be given to athletes only by prescription.

CH 8: Calcium (2)

Food sources: •Dairy products (milk, yogurt); fish (sardines, salmon). •Dark green leafy vegetables; calcium-set tofu, legumes; nuts. •Fortified products (juice, cereal). Absorption and bioavailability: •Lactose and vitamin D in milk may facilitate absorption. •Phytates in legumes and oxalates in spinach may decrease absorption.

CH 8: Phosphorus (2)

Food sources: •Distributed widely in foods: dairy foods such as milk and cheese, seafood, meats, eggs, nuts, seeds, grain products, vegetables. •Phosphorus is a common food additive. •High content in soft drinks. •Most Americans consume about twice the R D A for phosphorus.

CH 7: Vitamin D (1)

Food sources: •Fatty fish (salmon, mackerel, sardines, and catfish) contain 200-500 I U in 3 oz. •Shitake mushrooms contain 250 I U in four mushrooms. •Small amounts in egg yolks and butter. •Fortified foods (milk, cereals, orange juice). We get about 90 percent of our vitamin D from sunlight, 10 percent from food.

CH 7: Folate (2)

Food sources: •Green leafy vegetables, like spinach. •Organ meats like liver and kidney. •Whole grains, legumes. •Fruits like oranges, bananas, and papayas. •Fortified grains (average 140 mcg/100 grams of food). Functions: •Critical role in the metabolism of methionine, an essential amino acid. •Critical to formation of D N A. •Needed during periods of rapid cell division such as red blood cell formation and early pregnancy. •Involved in homocysteine metabolism.

CH 7: Vitamin A (1)

Food sources: •Preformed vitamin A in animal foods: liver, butter, cheese, egg yolks, fish liver oils, and fortified milk. •Beta-carotene in dark-green leafy and yellow-orange vegetables; some fruits. Major functions: •Maintenance of epithelial cells. •Vision—night and peripheral. •Bone development. •Immune system. •Beta-carotene functions as an antioxidant.

CH 8: Magnesium (2)

Food sources: •Widely distributed in foods: nuts, seafood, green leafy vegetables, other fruits and vegetables, black beans and whole-grain products. •Hard water, bottled water. Major functions in humans: •50 to 60 percent stored in skeletal system. •About 1 percent in extracellular fluid. •The rest is in soft tissues such as muscle, component of many enzymes. •Part of A T Pase; involved in cardiovascular, neuromuscular, and hormonal functions; helps regulate protein synthesis, 2,3-B P G.

CH 8: Food Sources of Nonheme Iron

Found in both plant and animal foods. •100 percent in plant foods. •20 to 70 percent in animal foods. Good sources: dried fruits, vegetables, legumes, whole-grain products. Cooking in iron pots or skillets contributes iron to diet. Factors affecting nonheme iron absorption: •Vitamin C helps absorb nonheme iron. •Adding meat to plant foods ↑ nonheme iron absorption. •Various factors (tannins, phytic acid, oxalic acid, calcium) decrease iron bioavailability.

CH 8: Function of Zinc

Found in virtually all body tissues. Involved in over 300 enzymes. •Promote immune system functions. •Promote eye health. •Promote wound healing. •Produce energy in lactic acid system. •Synthesis of D N A, protein, and insulin. •Support cellular and body growth. •Promote bone formation. •Promote red blood cell production. •Regulate gene expression. •Optimize the senses of taste and smell.

CH 7: In general, how do deficiencies or excesses of vitamins influence health or physical performance?

Four stages of vitamin deficiency: •Preliminary stage. •Biochemical deficiency stage. •Physiological deficiency stage. •Clinically manifest vitamin deficiency stage.

CH 8: Functions of copper

Functions as a cofactor for many metalloenzymes. •Most are involved in oxidation processes. Works closely with iron in oxygen metabolism. Is needed for intestinal absorption of iron. Helps in the formation of hemoglobin. Is involved in the activity of a specific cytochrome. Is a component of ceruloplasmin and superoxide dismutase.

CH 9: Body Temperature Regulation: Hypothalamus Control

Functions as a thermostat. Input. •Receptors in the skin. •Blood temperature. Output: •Circulatory system compensation. •Muscle contraction. •Sweating .

CH 9: How should carbohydrate be replaced during exercise in the heat?

Goal is to consume carbohydrate without impairing water absorption. Both water and carbohydrate intake during exercise may enhance performance, but the combination is more effective than either alone. Recommendations for sports drinks: •6 to 10% solutions (some athletes may experiment with higher concentrations). •Multiple sources of carbohydrate.

CH 9: A C S M Fluid Intake Guidelines: During Competition 1

Goal is to prevent excessive dehydration (>2% body weight loss from water deficit). Determine your sweat loss for a given intensity and duration of exercise in the heat. •This will provide you with an estimate for fluid intake during exercise. Drink about 0.4 to 0.8 liter fluids/hour (about 14 to 28 oz). •Smaller athletes may consume 14 oz, or about 3 to 4 oz/15 minutes. •Larger athletes may consume 28 oz, or about 7 oz/15 minutes. •Athletes can adjust the amounts according to personal needs. Drink cold water when carbohydrate intake is of little or no concern, such as in endurance events of less than 50 to 60 minutes. •C E S may be consumed during such events if preferred but provide no advantages over water alone.

CH 9: A C S M Fluid Intake Guidelines: Before Competition and Practice 1

Goal is to start in a state of euhydration with normal plasma electrolyte levels. Drink slowly about 5 to 7 ml/kg (0.08 to 0.11 ounce/pound) body weight at least 4 hours prior to exercise. •For an athlete weighing 70 kg (154 pounds), this would approximate 350 to 490 ml, or 12 to 17 ounces of fluids. •Athletes weighing more or less will drink accordingly. Drink another 3 to 5 ml/kg body weight about 2 hours prior to exercise if no urine is produced or the urine is dark or highly concentrated. •Your urine should be clear, pale yellow before competition or practice.

CH 8: Food Sources of Zinc

Good food sources: •Meat, milk, and seafood. •3 ounces of meat contain 30 to 50 percent of the R D A. •1 oyster contains about 70 percent. •Whole grain products and legumes are good sources, but contain phytates and fiber. Phytates and fiber may decrease bioavailability.

CH 8: Functions of Minerals in Humans

Growth and development. •Building blocks for body tissues: bones, teeth, muscles, organic structures. Metabolic regulation. •Metalloenzymes, antioxidant enzymes, and electrolytes. •Involved in muscle contraction, normal heart rhythm, nerve impulse conduction, oxygen transport, oxidative phosphorylation, enzyme activation, immune function, antioxidant activity, bone health, acid-base balance of the blood, and maintenance of body water supplies. Not a source of energy.

CH 7: Vitamin B6 Supplementation—Health Effects

Has been used to treat nausea during pregnancy, mental depression associated with the use of oral contraceptives, and P M S. May lower homocysteine. •Discussed later relative to C H D. High levels can cause peripheral nerve damage: •Loss of sensation from limbs. •Impaired gait.

CH 7: Vitamin K Supplementation

Health Effects: •Inverse relationship between vitamin K intake and risk for osteoporosis. •Consuming excess vitamin K may reduce effectiveness of anticoagulant medication. Physical Performance: •No studies have evaluated the ergogenic effects of vitamin K supplementation on physical performance, does not appear to play a role.

CH 8: Selenium Supplementation

Heart disease. •As noted, food fortification with selenium has prevented Keshan disease caused by such deficiency in China. •May help prevent L D L oxidation, a risk factor for cardiovascular disease. Effect on exercise performance. •Limited research with selenium by itself. •Often combined with other antioxidants in a "cocktail". •No antioxidant effect on muscle tissue damage. •No performance-enhancing effect.

CH 8: Risk Factors for Osteoporosis

Heredity Positive family history Race White or Asian Gender Female Menstrual status Postmenopausal; amenorrheic Age Advanced age Exercise Physical inactivity; bed rest Diet Inadequate calcium; inadequate vitamin D; excessive coffee; excessive alcohol Tobacco Cigarette smoking Alcohol Excessive use Stress Excessive stress; anxiety Medications Certain medications increase calcium losses Hormonal status Low estrogen; low testosterone

CH 7: How are vitamin needs determined?

Historically, recommended intakes were established to prevent vitamin-deficiency diseases. •Example: Amount of vitamin C to prevent scurvy. Today, recommendations incorporate the role of vitamins in health promotion and chronic disease prevention. •Example: Amount of vitamin C to promote optimal immune health and prevent cancer and other chronic diseases.

CH 9: High Blood Pressure

Hypertension, the silent disease. •A form of peripheral vascular disease by itself. •Major risk factor for C H D and stroke. Cause unknown in 90% of cases. •Essential hypertension. Major determinants of blood pressure. •Blood volume. •Resistance to blood flow.

CH 9: Potassium—Major Functions

Important intracellular electrolyte. Works with sodium and chloride. •Electrical impulses. Glucose transport into cells. Glycogen storage. Production of high-energy compounds.

CH 8: Functions of Iron

Important to a wide variety of metabolic processes. Major function is formation of compounds essential to use of oxygen. •Formation of hemoglobin, myoglobin, cytochromes, oxidative enzymes. The remainder of iron is stored in the body as protein compounds known as ferritins.

CH 9: Body Temperature Control

Inadequate body compensation for heat loss or gain. Hypothermia (low body temperature). •Muscular incoordination. •Mental confusion. Hyperthermia (increased body temperature). •Weakness and fatigue. •Heat illnesses.

CH 8: Causes of Iron Deficiency in Athletes

Inadequate dietary intake of iron. Excessive menstruation. Various exercise protocols. •May elevate hepcidin, decreasing iron absorption. Iron loss through urine, feces, and sweat. •Hematuria—presence of hemoglobin or myoglobin in urine. •Foot contact in runners (hemolysis). •Gastrointestinal inflammation and bleeding. •Use of aspirin or N S A I D S, leading to G I bleeding. training at high altitudes

CH 8: Stages of Iron Deficiency: Iron Deficiency Without Anemia

Iron depletion: •Depletion of bone marrow stores. •Decrease in serum ferritin and other markers of iron storage. •Hemoglobin levels still normal. Iron-deficiency erythropoiesis: •Further decrease in serum ferritin. •Less iron in the hemoglobin (less circulating iron), but hemoglobin levels in the blood still normal.

CH 9: A C S M Position Stand: Exercise and Hypertension

Key Points. •Exercise programs including aerobic endurance and resistance exercise help reduce blood pressure. •Exercise should be done daily for 30 minutes or more. •A higher level of physical activity is recommended; fitter people with hypertension have lower blood pressure than those who are less fit. •Even a single session exercise bout provides an immediate reduction in blood pressure, which can last all day.

CH 7: Vitamin E Functions

Key role is to serve as an antioxidant in the cell membrane: •Prevent oxidation of cell phospholipids. •Prevent oxidation of vitamin A. May play a key role in the synthesis of hemoglobin. May serve as a pro-oxidant by activating enzymes in the mitochondria to improve cellular oxygen utilization. Theorized to help prevent the development of several chronic diseases, or muscle tissue damage during exercise.

CH 8: Calcium and Kidney Stones

Kidney stones may form from calcium and oxalate in urine production. Kidney stones are not caused by dietary calcium; oxalate is the problem. Calcium researchers indicate increased calcium intake may help reduce formation of kidney stones. •Calcium can bind with oxalates in the intestine and lead to its excretion, thus decreasing the amount of oxalate in the body.

CH 9: A C S M Fluid Intake Guidelines: After Competition and Practice 2

Leisurely replacement (24-hour recovery). •Eat a diet rich in wholesome, natural foods adhering to healthy eating practices to help replenish needed electrolytes. •Extra salt may be added to meals when sodium losses are high. •Drink fluids with added sodium or consume salty foods or snacks.

CH 7: Vitamin D (2)

Light-skinned person in a bathing suit with no sunscreen can make 20,000 to 30,000 IU in 30 minutes: •African-Americans may need up to 10 times as much sunlight to make that amount; vitamin D formation also decreases with age. Hand, arm, and face exposure: •RDA can be obtained with 10 to 20 minutes in the summer sun, 2 to 3 times per week. Need longer exposure time in the winter: •May be difficult to obtain sufficient amounts in northern latitudes.

CH 7: Choline Supplementation

Little research attention to the effect of choline supplementation on health status. Preliminary studies have shown supplementation will increase blood choline levels at rest and during prolonged exercise. Some studies showed decreased run time and improved mood states while other have found no effect on aerobic or anaerobic performance. Prudent recommendations: •Supplementation not recommended.

CH 7: Vitamin B12 Deficiency

Liver stores may last for years. Deficiency is most common in vegans and those experiencing malabsorption from the small intestine as a result of inflammation of the stomach and/or insufficient production of H C l or intrinsic factor. Adverse health effects: •Megaloblastic and pernicious anemia. •Nerve damage; paralysis. No research available relative to the direct effect of a deficiency on performance, but anemia may impair exercise performance.

CH 9: Sodium and Potassium Balance

Low sodium concentration leads to a decrease in blood volume. •Stimulates kidney to release renin. •Produces a form of angiotensin. •Stimulates the adrenal glands to secrete aldosterone. •Increases sodium resorption in kidney, but increases potassium excretion. Therefore, with low potassium, aldosterone synthesis and release is decreased which decreases potassium excretion.

CH 7: Vitamin Supplements: Ergogenic Aspects

Many athletes use vitamin supplements: •Most commonly used supplements were multivitamin-multiminerals, vitamin C, vitamin D, vitamin-enriched water, protein powder, fatty acids, probiotics, and plant extracts. •Elite athletes use supplements more than college or high school athletes. •Women use supplements more often than men. •Athletes use supplements more than the general population and some take high doses that may lead to nutritional problems.

CH 7: Vitamin B6 Deficiency

May be seen in alcoholics, those with genetic conditions impacting its metabolism, and those on certain medications. Sometimes found in endurance athletes and those on low-energy diets. Deficiency: Health Effects. •Nausea, impaired immune function, skin disorders, mouth sores, weakness, mental depression, anemia, and epileptic-like convulsions. Deficiency: Physical Performance: •Anemia and impaired carbohydrate metabolism could impair endurance performance. •Some suggest impairment in fine motor control sports.

CH 8: Zinc Deficiency (2)

May lead to impaired growth and development in children. •May be responsible for 4 percent of global child morbidity and mortality. Affects the epidermal, GI, central nervous, immune, skeletal, and reproductive systems. Symptoms of deficiency: •Failure to grow properly, impaired wound healing, and depressed appetite. •Other symptoms include weight loss, taste abnormalities, mental depression, and impotence. Authorities indicate a medical examination is necessary to determine the presence of a zinc deficiency versus other causes.

CH 8: Exercise and Bone Health (1)

Mechanical loading will add bone. •Dynamic exercise. •College-age females increased hip and spine bone mass with 10 maximal vertical jumps 3 days a week for 6 months. Engaging in physical activity during youth is more osteogenic than during adulthood. •Adequate dietary calcium is an important factor. •Get bone in your bone bank by age 30.

CH 9: Hyponatremia: Signs and Symptoms

Mild cases. •Bloating. •Puffiness of hands and feet. •Nausea. •Vomiting. •Headache. Severe cases. •Seizures. •Coma. •Respiratory arrest. •Permanent brain damage. •Death.

CH 8: What are minerals, and what is their importance to humans?

Minerals are inorganic elements found in nature. •Found in soil and incorporated in growing plants. •Most animals get their mineral nutrition from the plants they eat. Humans obtain minerals from both plant and animal foods. •Drinking water may also be a good source of several minerals, including fluoride. •Minerals must be replaced regularly as they are excreted from the body in sweat, urine, and feces.

CH 7: Vitamin D Functions (1)

Most tissues and cells in the body have receptors for the hormonal form of vitamin D. •200 to 2,000 genes are controlled by vitamin D. Central role in bone metabolism through its effect on calcium and phosphorus. •Helps to absorb calcium from the intestinal tract and the kidneys, helping to maintain normal serum calcium levels and proper bone metabolism. •Helps regulate phosphorus metabolism, another mineral essential in bone formation.

CH 7: Vitamin C

Name, terms: •Ascorbic acid. D R I: •R D A = 90 mg/day males; 75 mg/day females. •U L = 2,000 mg/day. Food Sources: •Fruits and vegetables; primarily citrus fruits and leafy part of green vegetables.

CH 7: Vitamin D (cholecalciferol)

Name, terms: •Cholecalciferol (vitamin D3). •Calcitriol—Physiologically active hormonal form. D R I (based on minimal exposure to sunlight): •Infants 0 to 12 months: AI = 10 mcg cholecalciferol or 400 IU. •1 to 70 years old: AI = 15 mcg or 600 IU. •>70 years: AI = 20 mcg or 800 IU. •UL for those over 9 = 100 mcg or 4,000 IU.

CH 7: Vitamin B12

Name, terms: •Cobalamin. D R I: •R D A = 2.4 micrograms/day (mcg/day). •No U L has been established. Food sources: •Only found in animal foods: meat, fish, poultry, cheese, eggs, and milk. •Found in fortified foods, such as breakfast cereals.

CH 7: Folate (1)

Name, terms: •Folate (natural form). •Folic acid (synthetic form). •Folacin (collective term). D R I: •Dietary folate equivalents (D F E). •Absorption of folic acid from fortified foods or dietary supplements is about 1.7 times that of natural food folate. •R D A = 400 D F E/day; 600 D F E in pregnancy and 500 D F E in early stages of lactation. •UL = 1,000 m c g (1 mg) D F E/day.

CH 7: Niacin (Vitamin B3)

Name, terms: •Nicotinic acid; nicotinamide; antipellagra vitamin. D R I: expressed as niacin equivalents (NE): •1 N E = 1 mg niacin or 60 mg tryptophan. •R D A = 16 NE adult males; 14 NE adult females. •U L = 35 mg/day. Food sources: •Foods with high protein content. •Lean meat, fish, poultry, whole grain cereals, legumes, enriched foods.

CH 7: Vitamin K (Menadione)

Name, terms: •Phylloquinone—plant form. •Menaquinone—animal form. •Menadione—synthetic form. D R I: •AI = 120 and 90 mcg/day for adult males and females. •No UL has been established.

CH 7: Vitamin B6 (Pyridoxine)

Name, terms: •Pyridoxine, pyridoxal, pyridoxamine. D R I: •R D A = 1.3 mg/day age 19 to 50. •1.7 and 1.5 for males and females > age 51. •U L = 100 mg/day. Food sources: •Widely distributed in foods. •Meats, poultry, fish, wheat germ, whole grains, brown rice, eggs.

CH 7: Vitamin A (retinol)

Name, terms: •Retinol (physiologically active form of vitamin A). •Human body can form retinol from provitamins known as carotenoids, primarily beta-carotene. Dietary reference intakes (D R I): •Retinol equivalents (R E), retinal activity equivalents (R A E), or international units. •1 R A E = 1 mcg retinol, 12 mcg beta-carotene, or 3.3 I U. •R D A = 900 mcg R A E or 3,000 I U for adult males, 700 mcg R A E or 2,300 I U for adult females. •U L = 3 mg/day, or 10,000 I U. •No U L has been established for carotenoids.

CH 7: Thiamin (Vitamin B1)

Name, terms: •Vitamin B1. D R I: •R D A = 1.2 mg/day males; 1.1 mg/day females. •No U L has been established. Food sources: •Widely distributed in plant and animal foods. •Whole grain cereals, beans, pork. •One lean pork chop contains 50 percent of the R D A. •Several fortified, ready-to-eat cereals contain 100 percent of the R D A for thiamin, as well as most of the other B vitamins.

CH 7: Riboflavin (Vitamin B2)

Name, terms: •Vitamin B2. D R I: •R D A = 1.3 mg/day for adult males; 1.1 mg/day for adult females. •No U L has been established. Food sources: •Widely distributed in plant and animal foods. •Major food sources include milk and dairy products (riboflavin quickly degrades with light; do not store in clear glass containers) •Liver, eggs, dark-green leafy vegetables, wheat germ, yeast, whole-grain products, enriched breads and cereals

CH 7: Vitamin E

Name, terms: •alpha-tocopherol (most common form in the bloodstream and dietary supplements). •gamma-tocopherol (lower biological activity). D R I: •R D A = 15 mg alpha-tocopherol. •1 mg = 1.5 IU. •U L = 1,000 mg or 1,500 I U.

CH 8: Zinc Supplementation (2)

Neutral. •Appears to have little effect on immune functions and prevention of the common cold. •Currently no evidence to support the use of zinc supplementation in the prevention of type 2 diabetes. Detrimental. •Acute toxicity: Nausea, vomiting, loss of appetite, abdominal cramps, diarrhea, and headaches. •Chronic toxicity: Low copper status, altered iron function, and reduced immune functions.

CH 7: Water-Soluble Vitamins

Nine vitamins: •Vitamin B complex (8 individual vitamins). •Vitamin C (ascorbic acid). Not stored in the body. •Excess is excreted in urine. Deficiency symptoms may be noted in 2 to 4 weeks. •May reduce physical performance capacity. Most act as components of coenzymes necessary for energy metabolism.

CH 7: Pantothenic Acid Supplementation

No health benefits for well-nourished individuals. No effect on coenzyme A levels or physical performance. Large doses have been known to cause diarrhea. Prudent recommendations: •Supplementation is not recommended. •A balanced diet should provide adequate pantothenic acid for the healthy, physically active individual.

CH 9: How is body water regulated?

Normohydration (euhydration). •Normal body water stores. Hyperhydration. •Process of increasing body fluids. Above normal levels of body water Dehydration. •Process of losing body fluids. Hypohydration. •Low levels of body water. •Hypohydration and dehydration are used interchangeably.

CH 7: Hypervitaminosis

Not likely to occur from natural foods. Most likely due to excessive intake of: •Vitamin supplements. •Fortified foods. •Combination of the two. Vitamins begin to function like drugs and induce toxic reactions. U L has been established for most vitamins.

CH 8: Prudent Recommendations for Magnesium

Obtain adequate Mg through a balanced diet. •The DASH diet plan. Obtaining magnesium from fortified foods or supplements may be recommended for athletes, particularly females, in weight-control sports. •Caveat: Do not exceed 350 milligrams/day with supplements.

CH 7: Vitamin C Prudent Recommendations

Obtain vitamin C naturally through foods: •Eat more fruits and vegetables. While supplementation may be recommended for some, further research is needed.

CH 7: Vitamin K Sources

Plant foods: vegetable oils; green leafy vegetables: •Main dietary source. •3 oz spinach contain 380 mcg. Animal foods: meats and milk: •Lower concentrations. •3 oz meat contain less than 1 mcg. Synthesis in body: •Intestinal bacteria form menaquinone.

CH 7: Vitamin E Food Sources

Polyunsaturated vegetable oils. •1 tablespoon contains about 5 mg. Sunflower seeds, almonds, peanuts, wheat germ, and several vegetables are also good sources. •¼ cup sunflower seeds contains about 8 mg. •½ cup cooked spinach contains about 2 mg. Meats, refined grains, and dairy foods are typically poor sources.

CH 9: Hyperhydration

Possible beneficial effects. •Help maintain temperature regulation and cardiovascular functions when fluids may not be ingested during exercise. No effects. •Little evidence of beneficial effects in comparison to euhydration. A C S M recommends hyperhydration. Glycerol-induced hyperhydration covered later.

CH 8: Chromium Deficiency (2)

Possible losses or increased needs of chromium by athletes: •Increased intensity and duration of exercise may increase urinary excretion. •A high-carbohydrate diet may increase Cr needs. •Weight loss for performance could decrease dietary Cr intake. Adverse effects on carbohydrate and protein metabolism, if any, could impair performance.

CH 8: Does exercise increase my need for minerals?

Possible reasons for increased needs. •Losses of some minerals in sweat. •Losses of some minerals in urine. •Losses of some minerals from the G I tract. •Losses of some minerals from excess menstrual flow. •Increased need from effects of amenorrhea. •Increased need in male endurance athletes with decreased trabecular bone mass.

CH 9: Do some individuals have problems tolerating exercise in the heat?

Predisposing factors associated with heat injury: •Poor physical fitness. •Gender. •Age. •Obesity. •Previous heat illness. •Not heat acclimated.

CH 8: In general, how do deficiencies or excesses of minerals influence health or physical performance?

Preliminary stage. •Reduced intake with low energy intake. •Reduced bioavailability due to form consumed. Biochemical deficiency stage. •Decrease body pool of a mineral. Physiological deficiency stage. •Appearance of unspecified symptoms; loss of appetite, weakness, fatigue. Clinically manifest deficiency. •Clinical symptoms occur; health and performance suffer.

CH 7: Example of Stages of Vitamin Deficiency (Example: Vitamin B12)

Preliminary stage: •Individual switches to a vegan diet and avoids fortified foods. Biochemical deficiency stage: •Serum levels of vitamin B12 decrease. Physiological deficiency stage: •General feelings of weakness occur. Clinically manifest vitamin deficiency stage: •Pernicious anemia develops. Note: First 3 stages represent subclinical malnutrition.

CH 7: Niacin Supplementation—Health Effects

Prescription formulations: •Immediate-release. •Sustained-release. •Extended-release. Large doses may cause flushing, burning, and tingling sensation. High doses may improve serum lipid profile. •Reduce LDL-cholesterol and improve HDL-cholesterol. •Reduce risk for stroke and heart attack. Excess may cause liver damage. Use only under medical care.

CH 9: Exercise-Associated Hyponatremia: Prevention and Treatment

Prevention: •Do not consume fluids in excess before, during, or after exercise. •Consume extra salt in days before prolonged exercise. •Body weight should not increase during exercise. •Consume sports drinks with increased sodium content. Treatment: •Hypertonic beverages. •For severe hyponatremia, intravenous hypertonic (for example, 3%) sodium chloride solutions will speed recovery and improve outcomes. •Athletes who do not recover rapidly should be sent to the nearest medical emergency facility.

CH 9: Sodium: Major Functions

Principal electrolyte in extracellular fluids. •Nerve impulse transmission. •Muscle contraction. Maintains normal body-fluid balance and osmotic pressure. Essential for control of blood volume and pressure. Component of sodium bicarbonate. •Helps maintain normal acid-base balance. •Potential ergogenic effects.

CH 9: Involuntary Dehydration 1

Prolonged aerobic endurance events. •In cold environments: dehydration of 3% has marginal influence on aerobic endurance performance. •In heat-stress environments: adverse effects of dehydration.

CH 7: Vitamin A (5)

Prudent recommendations: •No advantage for the active individual to supplement the diet with vitamin A. •No beneficial effect on physical performance. •Megadoses may have undesirable effects. •Beta-carotene supplementation will e discussed later in the chapter.

CH 8: Magnesium Deficiency (1)

Rare in healthy adults. Those at greatest risk: •Those with poorly controlled diabetes. •Those taking certain medications. •Alcoholics. •Elderly—increased urinary excretion and reduced absorption. Symptoms could include muscle weakness, twitching, and cramping; apathy; cardiac arrhythmias. Chronic deficiency associated with type 2 diabetes, metabolic syndrome, hypertension, cardiovascular disease, osteoporosis, migraines, asthma, and colon cancer.

CH 7: Vitamin C Deficiency—Health Effects (1)

Rare in industrialized societies. •Smoking, aspirin, oral contraceptives, and stress increase need. Major deficiency disease is scurvy (disintegration of the connective tissue in the gums, skin, tendons, and cartilage): •Bleeding gums. •Rupture of blood vessels in the skin. •Impaired wound healing. •Muscle cramps. •Weakness. •Anemia.

CH 7: Free Radicals

Reactive oxygen/nitrogen species (R O N S). Free radicals are produced during normal metabolic processes and are involved in normal cell functioning, but may be produced in excess under certain circumstances and be damaging to cellular constituents.

CH 8: Phosphorus Prudent Recommendations

Reduce dietary intake of dietary sources high in phosphates. •Check food labels for the word phosphate. •Eating a diet rich in unprocessed foods may help reduce dietary phosphate intake. For use as an ergogenic aid. •Practice in training; 5 to 6 days of phosphate supplementation. •Use sparingly and under the guidance of a health professional.

CH 9: Can exercise help prevent or treat hypertension? 1

Regular, mild- to moderate-intensity aerobic exercise is recommended to reduce high blood pressure. •May induce sympathetic relaxation of blood vessels. •May contribute to weight loss. •May decrease blood pressure in normotensives, and more so in hypertensives. •Even small reductions reduce risk of C H D and stroke. Resistance training may be effective in lowering blood pressure.

CH 8: Calcium and Sports Performance

Research on the effect of supplementation of sports performance is almost nonexistent. One study with acute supplementation: •500 mg high-calcium or 80-mg low-calcium drink 60 minutes before 90-minute run followed by 10-kilometer time trial. •No effect on energy metabolism. May be beneficial to help maintain bone mass in some female and male athletes.

CH 7: Vitamin D Deficiency—Health Effects (1)

Rickets in children and osteomalacia in adults contribute to softening and weakening of bones. Muscle weakness: impaired calcium metabolism in muscle. Could lead to increased cell proliferation. •Relation of sun exposure to cancer development. •Solar U V B irradiance and/or vitamin D have been found inversely correlated with incidence, mortality, and/or survival rates for breast, colorectal, ovarian, and prostate cancer and Hodgkin's and non-Hodgkin's lymphoma.

CH 7: Vitamin D Supplementation—Physical Performance

Several possible ergogenic mechanisms: •May improve post-exercise recovery by inhibiting myostatin. •Increase force and power production via increased calcium kinetics and cross-bridge cycling. •Influence muscle growth by augmenting testosterone production and androgen binding. Doses ranging from 4,000 to 8,500 IU/day for 4 weeks to 6 months were shown to significantly increase upper and lower body strength in subjects 18 to 40 years of age.

CH 7: Niacin Supplementation—Physical Performance

Several studies report no ergogenic effect: •10-mile run. •Prolonged cycling. Not recommended. •May impair endurance performance by interfering with fat metabolism during exercise. One study suggests niacin may be helpful as a means to dissipate body heat during exercise. •Further investigation is needed.

CH 9: Sodium: Deficiency and Excess

Sodium is critical to life. Human body has a very effective regulatory feedback mechanism to maintain long-term control of sodium and water balance. Hypothalamic control of aldosterone release from the adrenal gland. Aldosterone stimulates kidneys to reabsorb sodium. •↑ aldosterone with low blood osmolality (low sodium levels). •↓ aldosterone with high blood osmolality (high sodium levels). Short-term deficiencies may impair exercise performance.

CH 9: Major Electrolytes:

Sodium, Chloride, and Potassium

CH 9: Nutrition Facts Label Terms for Sodium

Sodium-Free or Salt-Free. •Less than 5 milligrams per serving. Very Low Sodium. •35 milligrams or less per serving. Low Sodium. •140 milligrams or less per serving. Reduced-Sodium or Less Sodium. •At least 25 percent less than the regular product. No Salt Added. •Amount of sodium per serving must be listed.

CH 8: Mineral Nutrition

Some concern with inadequate intake. •Calcium, iron, potassium, zinc. Athletes. •Most, especially males, obtain adequate amounts. •Weight-control sports at risk. Body may compensate for decreased dietary intake. •Increased absorption. •Decreased excretion. Deficiencies may impair physical performance. Excessive intake my impair health. Toxic minerals. •Lead, mercury, cadmium, arsenic.

CH 7: Should physically active individuals take vitamin supplements?

Some possible reasons to take supplements: •Weight-control sports. •Poor dietary habits. •Pregnancy. •Elderly, senior athletes. •Consult with your health professional. Interesting hypotheses suggest that antioxidant vitamin supplements may help prevent muscle tissue damage during training. Research suggests that supplementation with vitamin D may help athletes train and compete more effectively.

CH 9: Skin Wetting

Sponging or using a spray bottle: •Decrease sweat loss. •May cool the skin. •Sense of psychological relief. No effects: •Core temperature. •Cardiovascular responses. •May encourage faster pace, more heat production.

CH 8: Calcium Prudent Recommendations

Start at a young age. •Adequate daily calcium intake. •Weight-bearing exercise. Calcium supplements may be recommended to obtain the R D A if a sufficient amount is not obtained from the normal diet.

CH 8: Iron Supplementation (3)

Supplementation to individuals who are iron saturated. •Iron supplementation offers no benefits to individuals with normal hemoglobin and iron status. •May be detrimental to health: Hemochromatosis in susceptible individuals may lead to cirrhosis of the liver; accumulation in other body organs such as the heart which can lead to irregular heartbeat and contribute to heart failure; may be fatal to young children.

CH 8: Iron Supplementation (2)

Supplementation to individuals who have iron-deficiency without anemia. •May improve some measures of cognitive function. •May provide some health benefits to women during pregnancy as iron need increases. •Whether or not iron supplementation improves exercise performance is debatable.

CH 8: Iron Supplementation (1)

Supplementation to individuals with iron-deficiency anemia. •May correct iron-deficiency anemia and improve health status and exercise performance capacity. •May improve various aspects of mood, memory, and intellectual ability. •May improve quality of life measures and exercise performance in cardiac patients.

CH 7: Riboflavin Supplementation

Supplementation: Health Effects. •Has no health benefits for well-nourished individuals. Supplementation: Physical Performance. •Only one reputable study conducted and reported no beneficial effects on performance. Prudent recommendations: •Supplements not recommended. •Athletes should consume a well-balanced diet.

CH 7: Vitamin B12 Supplementation

Supplementation: Health Effects. •May help treat pernicious anemia. Supplementation: Physical Performance. •No apparent effect on VO2 max or endurance performance. Prudent recommendations: •Supplementation not normally warranted. •Vegans should consume food products fortified with vitamin B12. •Senior athletes should consume fortified foods or take a supplement.

CH 7: Vitamin A (3)

Supplementation: Health and physical performance: •Retinol supplements are not recommended unless under medical guidance. •Hypervitaminosis A: weakness, headache, loss of appetite, nausea, joint pain, skin peeling. •Excess vitamin A may also weaken bones: inhibits bone formation, leading to bone loss and contributing to osteoporosis; increased risk of hip fractures. •Excessive intake during pregnancy may be teratogenic. •Excess beta-carotene may cause carotenemia, a harmless yellowing of skin.

CH 7: Vitamin B6 Supplementation

Supplementation: Physical Performance: •Physically active individuals may need 1.5 to 2.5 the current R D A to maintain good B6 status. •Research suggests supplementation does not affect performance positively or negatively. Prudent recommendations: •Consume a well-balance diet. •Supplements not recommended for health or enhanced exercise performance. •Excess consumption over time may lead to adverse health effects.

CH 8: Calcium Supplements

Supplements come in different forms and amounts. •50 to 600 mg in calcium supplements. •Carbonate, citrate, lactate, gluconate. •Calcium from most supplements is absorbed as well as calcium from milk. •Often combined with vitamin D.

CH 8: Calcium (1)

Symbol: Ca. Almost 2 percent of body weight. Dietary Reference Intakes (D R I): •AI = 1,000 mg (age 19 to 50). •AI = 1,300 mg (age 9 to 18). •AI = 1,200 mg men (age 70+) and women (age 51+). •UL = 2,000 to 2,500 mg.

CH 9: Chloride 1

Symbol: Cl− D R I. •A I = 2.3 grams, or 2,300 mg (age 9 to 50). •U L = 3.5 grams, or 3,500 mg. •D V = 3,500 mg. Food sources. •Dietary intake closely associated with sodium intake. •60% of common table salt.

CH 8: Chromium

Symbol: Cr. Dietary Reference Intakes (D R I): •A I = 30 to 35 mcg for males, 20 to 25 mcg for females. •U L = None established. Food sources: •Whole-grain products, organ meats, egg yolks, pork, oysters, nuts, fruits and vegetables. •Beer. •A half-cup of broccoli provides about 25 percent of the A I.

CH 8: Copper

Symbol: Cu. Dietary Reference Intakes (D R I): •R D A = 900 mcg (0.9 mg) for adults (age 19 to 50). •U L = 10,000 mcg (10 mg). •D V = 2 mg.

CH 9: Potassium

Symbol: K (Kalium). D R I. •A I = 4.7 grams, or 4,700 mg (age 14 and above). •U L = Not established. •D V = 3.5 grams (less than the A I).

CH 8: Magnesium (1)

Symbol: Mg. Dietary Reference Intakes (D R I): •R D A = 400 to 420 mg for men; 310 to 320 mg for women. •U L = 350 mg, but only pharmacological forms of magnesium; no restrictions from food sources.

CH 9: Sodium

Symbol: Na (Natrium). D R I. •AI = 1,500 milligrams (age 9 to 50). •UL = 2,300 milligrams. •DV = 2,400 milligrams. •Note: Larger amount than the UL. Average global sodium intake in 2010 was 3,950 milligrams/day. Distributed widely in nature, but in small amounts in natural foods. Table salt: 1 teaspoon contains 2,000 mg of sodium. Processed foods may contain substantial amounts. To consume less. •Drain and rinse canned vegetables. •Use herbs and spices or salt substitutes.

CH 8: Phosphorus (1)

Symbol: P Dietary reference intakes (D R I): •R D A = 700 mg (age >19). •U L = 4 g.

CH 8: Selenium

Symbol: Se. Dietary Reference Intakes (D R I): •R D A = 55 mcg for adult males and females. •U L = 400 mcg. Food sources: •Brazil nuts. •Kidney and liver, seafood such as tuna, and other meats. •Grains, fruits, and vegetables grown in selenium-rich soil.

CH 8: Zinc

Symbol: Zn. Dietary Reference Intakes (D R I): •R D A = 11 mg for adult males and 8 mg for adult females. •U L = 40 mg.

CH 8: Osteoporosis in Sports

The Female Athlete Triad. •Disordered eating (will be discussed in Chapter 10) creates an energy deficit and affects hormone status, including disturbed functioning of the hypothalamus and pituitary gland. •Amenorrhea. •Osteoporosis. Males are at less risk, but osteoporosis may occur with poor diets and weight loss.

CH 9: A C S M Fluid Intake Guidelines: After Competition and Practice 1

The goal is to fully replace any fluid and electrolyte deficit. Rapid replacement. •Drink 1.5 liters of fluid for every kilogram of body weight loss, or about 1.5 pints for each pound loss. •Consume about 1.0 to 1.5 grams of carbohydrate per kilogram body weight (about 0.5 to 0.7 gram per pound body weight) each hour for 3 to 4 hours. •For a 60-kg athlete, this would represent about 60 to 90 grams of carbohydrate per hour. •Consume adequate sodium. •Salty carbohydrate snacks, such as pretzels, may provide both sodium and carbohydrate.

CH 8: Can I obtain the minerals I need through my diet?

The key is to eat a wide variety of foods among and within the various food groups or food exchanges. •Remember, consumption of phytates, oxalates, and tannins can decrease mineral bioavailability. •Excessive intake of one mineral can negatively impact absorption of another. Basic principle of mineral nutrition is to eat natural foods that are rich in calcium, potassium, and iron, nutrients of "public health concern" in the United States.

CH 8: Osteoporosis (1)

The major health problem of inadequate calcium intake leading to calcium deficiency is osteoporosis. •Thinning and weakening of the bones related to loss of calcium stores. Various risk factors for osteoporosis.

CH 9: Lifestyle and High Blood Pressure

The more healthful lifestyle behaviors one develops, the greater will be the reduction in blood pressure. Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (J N C D E T) quantified the blood pressure-lowering effects of various behaviors: •Weight reduction (5 to 20 mmHg/10 kg). •D A S H eating plan (8 to 14 mmHg). •Dietary sodium reduction (2 to 8 mmHg). •Increased physical activity (4 to 9 mmHg). •Moderation of alcohol consumption (2 to 4 mmHg).

CH 9: Rehydration

The most effective technique. May have small benefits to performance in weight-control sports, such as wrestling. •Local muscular endurance. Benefits to endurance athletes. •Minimize increase in core temperature. •Minimize decrease in blood volume. •Maintain optimal race pace for longer time. A C S M position stand focuses on rehydration.

CH 9: Can exercise help prevent or treat hypertension? 2

The use of handheld weights might be contraindicated for some hypertensive individuals due to the pressor (elevated blood pressure and heart rate) response that can occur with upper-body exercise. Exercise snacks may be effective. •4×10-minute brisk walks daily.

CH 8: Calcium, Obesity, and Weight Control

Theories. •Low calcium levels stimulate an increase in calcitriol (vitamin D hormone), which can cause an influx of calcium into adipose cells, stimulating fat accumulation, while higher-calcium diets may inhibit the formation of body fat. •Calcium may promote fecal fat loss and oxidation. •Calcium may favor a decrease in energy intake. •Calcium may facilitate appetite control.

CH 7: Biotin Supplementation

There is no evidence that biotin supplementation enhances health or exercise performance. Prudent recommendations: •Supplements are unnecessary for the physically active individual. •Consume a diet that provides adequate amounts of biotin.

CH 8: Stages of Iron Deficiency: Iron-Deficiency Anemia

Third stage of iron deficiency. Symptoms: •Fatigue and weakness. •Paleness. •Shortness of breath. •Abnormally shapes fingernails (brittle, cupped). •Irritability. •Poor appetite. •Difficulty concentrating. •Feeling cold. •Headache. •Hair loss.

CH 9: How do I know if I am adequately hydrated?

Thirst. Urine color. •Should be clear, pale yellow. Deep yellow may indicate hypohydration. •Riboflavin vitamin may cause deep yellow urine color. Body weight changes. •Rapid body weight changes are due to body water loss or gain.

CH 8: Trace Minerals

Trace minerals are those for which quantities of 100 mg or less are needed daily. •Include chromium, copper, fluoride, iodine, iron, manganese, molybdenum, selenium, and zinc. The term ultratrace minerals is used for those whose requirements are expressed in micrograms (mcg or μg).

CH 8: Zinc Deficiency (1)

Uncommon, but may occur in North America. •Vegetarians. •Individuals with Crohn's disease. •Pregnant and lactating women. •Alcoholics. In developing countries that consume little meat, such as in Asia and Africa. •Diets rich in phytates. •Gastrointestinal losses of zinc with diarrhea.

CH 7: Vitamin C Supplementation

Undesirable side effects of megadoses: •Diarrhea. •Destruction of B12, excessive excretion of vitamin B6, decreased copper bioavailability. •Predisposition to gout, creating pain in the joints. •Formation of kidney stones. •Iron storage; oxidative effect of iron. •Rebound scurvy.

CH 7: Vitamin A (4)

Vitamin A supplementation—effects on sport (beneficial or detrimental): •Little theoretical value; no beneficial effect. •Note: Antioxidant effects of beta-carotene to prevent muscle tissue damage during exercise is discussed later.

CH 7: Vitamin D Deficiency—Physical Performance (1)

Vitamin D is status has been related to: •Injury prevention. •Rehabilitation. •Improved neuromuscular function. •Increased type II muscle fiber size. •Reduced inflammation. •Decreased risk of stress fracture. •Reduced risk of acute respiratory illness.

CH 7: What are vitamins and how do they work?

Vitamins are a class of complex organic compounds found in small amounts in most foods. Coenzyme Functions—necessary for enzymes to function properly. •B Vitamins. Antioxidant Functions—neutralize free radicals. •Beta-Carotene (Vitamin A). •Vitamin C. •Vitamin E. Hormone Functions.

CH 7: What vitamins are essential to human nutrition?

Water-soluble vitamins: •Thiamin. •Riboflavin. •Niacin. •Vitamin B6. •Vitamin B12. •Folate. •Biotin. •Pantothenic acid. •Vitamin C. •Choline (vitamin-like substance). Fat-soluble vitamins: •Vitamin A. •Vitamin D. •Vitamin E. •Vitamin K.

CH 9: Which is more important to replace during exercise in the heat: water, carbohydrate, or electrolytes?

Water. •Prevent or delay dehydration. Carbohydrate. •Provide energy. Electrolytes. •Prevent heat illness. Fluid-electrolyte replacement is important to individuals dehydrated from diarrheal disease as well as individuals exposed to exercise and/or environmental stress. The optimal content of fluid-electrolyte replacement beverages depends on many factors, not the least of which is the reason for fluid and/or electrolyte loss.

CH 8: Exercise and Bone Health (2)

Whether or not exercise prevents bone loss after menopause appears to be debatable. •Some contend resistance and weight-bearing exercise will prevent bone loss and may add bone. •Others contend that there is little evidence that exercise, even vigorous exercise, attenuates the menopause-related loss of bone mineral in women. •Adequate dietary intake of calcium and vitamin D are key.

CH 9: Chloride 2

Works closely with sodium. •Regulation of body water balance. •Electrical potential across cell membranes. •Helps form hydrochloric acid in the stomach. Deficiency is very rare. •Losses during exercise-induced sweating parallel those of sodium.

CH 9: Voluntary Dehydration

Wrestlers. •Sauna. •Diuretics. •Decreased intake of fluids. Results of studies on voluntary loss of 3 to 5% body mass on exercise performance are equivocal. •Little to no effect on strength or power. •Anaerobic muscular endurance tasks longer than 20 to 30 seconds may be impaired.

CH 7: Activation of Vitamin D

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CH 8: Major Physiological Functions of Minerals in Humans

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CH 8: Normal versus Osteoporotic Bone

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CH 8: Simplified Diagram of Iron Metabolism in Humans

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CH 9: Estimated Daily Water Balance in a Woman

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CH 9: Heat Exchange Mechanisms during Exercise

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CH 9: Physiological Effects of Dehydration

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CH 9: What are some of the potential health hazards of excessive heat stress imposed on the body?

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CH 9: Where is water stored in the body?

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CH 9: What environmental conditions may predispose an athletic individual to hyperthermia?

•Air temperature. •Relative humidity. •Air movement. •Radiation.

CH 7: Folate Prudent Recommendations

•All individuals should increase their intake of folate-rich foods, particularly fruits and vegetables, to obtain both folate and other health-promoting nutrients. •All women in childbearing potential should obtain 400 m c g D F E/day from a supplement and/or dietary sources. •Monitor daily intake of synthetic folic acid and limit intake to less than 1,000 m c g D F E to avoid negative impacts on health.

CH 7: Vitamin E Supplementation—Health Effects

•Antioxidant effects theorized to help prevent heart disease and cancer. •Research findings discussed later with other antioxidants.

CH 7: Vitamin C Functions

•Antioxidant that protects cells from free radical damage. •Synthesis of collagen, necessary for formation and maintenance of cartilage, tendon, and bone. •Formation of certain hormones and neurotransmitters, including epinephrine (adrenaline) during exercise. •Absorption of iron from the G I tract. •Synthesis of red blood. •Healing of wounds through development of scar tissue. •Regulates metabolism of folic acid, cholesterol, and amino acids. •Promotes health of the immune system.

CH 7: Vitamin C Deficiency—Health Effects (2)

•Associated with some forms of cancer, cardiovascular disease, age-related macular degeneration (A M D) and cataracts, and the common cold.

CH 7: Vitamin D Prudent Recommendations

•Athletes should consume a vitamin D-rich diet to optimize health and athletic performance. •Supplementation may be warranted for those with a history of stress fracture, or bone or joint injury. •Further research is needed to evaluate potential ergogenic effects. •Have blood levels of vitamin D assessed before supplementing.

CH 8: Zinc Deficiency (3)

•Athletes who obtain sufficient kcal generally obtain enough zinc to prevent a deficiency. •May occur in weight-control sports or diets low in animal protein and high in carbohydrate. •Sweat losses may approximate 8 to 9 percent of the R D A. •Reviews indicate exercise does not cause a zinc deficiency or that a marginal deficiency impairs performance.

CH 7: Essential Vitamins

•Cannot be synthesized in the body in sufficient quantity. •Cause deficiency symptoms when intake is inadequate. •Alleviate deficiency symptoms when added back into the diet.

CH 9: Environmental Heat and Exercise Performance: Possible Mechanisms of Fatigue

•Central neural fatigue caused by ↑ brain temperature. •Cardiovascular strain caused by changes in blood circulation. •Muscle metabolism changes caused by ↑ muscle temperature. •Dehydration caused by excessive sweat losses.

CH 7: Riboflavin Functions

•Component of two coenzymes necessary for energy metabolism, flavin mononucleotide (F M N) and flavin adenine dinucleotide (F A D). •Important for fatty acid and folate metabolism.

CH 8: Prudent Recommendations for Zinc

•Consume diet rich in protein foods. •Wrestlers, other weight-control athletes focus on zinc-rich foods. •Zinc supplementation is not warranted for most individuals, including athletes.

CH 9: Involuntary Dehydration: A C S M Position Stand

•Dehydration, especially in warm-hot weather, increases physiologic strain and perceived effort. •Dehydration can degrade aerobic exercise performance. •The greater the dehydration level, the greater the physiologic strain and impairment in performance. •The critical water deficit and adverse effects are related to the heat stress, exercise task, and the individuals unique biological characteristics.

CH 8: Chromium Deficiency (1)

•Difficult to determine if a chromium deficiency exists. •Theoretically, a deficiency could impair insulin activity and impair both health and physical performance. •Role in development of diabetes being studied. •Deficiencies have been associated with abnormal blood lipid levels, primarily elevated total cholesterol and triglyceride levels.

CH 7: Vitamin C Supplementation—Physical Performance

•Early and contemporary research indicates improvement in individuals who are vitamin C deficient, but not in those who are not deficient. •May be beneficial to heat acclimation, a topic that merits additional research with trained athletes. •Some studies indicate reduced severity of upper respiratory tract infections following ultra-endurance exercise. •Current research shows no benefit to immune system functions. •No apparent effect on exercise performance.

CH 9: What are the major functions of water in the body?

•Essential building material for cell protoplasm. •Protection of organs such as brain and spinal cord. •Maintenance of electrolyte balance and key cell functions. •Main constituent of blood. •Proper functioning of senses (eyes, ears). •Regulation of body temperature.

CH 9: Exercise-Associated Hyponatremia: Individuals at Risk

•Excessive drinking of fluids before, during, and after the event. •Considerable weight gain over the course of the event. •Slower finishers. •Females. •Low body weight. •Heat-unacclimatized, poorly trained individuals. •Individuals with high sweat sodium losses. •Novice participant. •Individuals who use N S A I D S.

CH 8: Prudent Recommendations for Chromium

•Glucose intolerant or those who have pre-diabetes or diabetes should consult a physician concerning supplementation. •Supplements do not appear to be warranted for the general population. •Take only 200 mcg at the most if you take supplements, possibly best as part of a multivitamin/mineral tablet. •The best source of chromium is a diet rich in whole grains, fruits, and vegetables.

CH 7: Vitamin D Deficiency—Health Effects (2)

•Higher risk of myocardial infarction. •Insulin resistance and increased risk of diabetes. •Increased blood pressure. •May affect mental health. •Associated with poorer cognitive function and greater risk of Alzheimer's disease.

CH 7: Vitamin D Deficiency—Physical Performance (2)

•Influence of vitamin D extends beyond calcium metabolism to include proper skeletal and cardiac muscle function, immune function, and cancer prevention. •Vitamin D has a recently discovered role in transcription of a binding protein for I G F-1, which is discussed in Chapters 6 and 13. •Problems with vitamin D receptor (V D R) transcription are thought to play a role in muscle weakness.

CH 9: How can I become acclimatized to exercise in the heat?

•Living in a hot environment confers a small degree of acclimatization. •Physical activity itself confers a significant amount of acclimatization. •In order to obtain full acclimatization, one must exercise in the heat. •Cut back on the intensity and/or duration of your normal exercise routine when ambient temperatures increase. •Gradually increase the intensity and duration of exercise. •Full acclimatization takes about 10 to 14 days, but longer in children.

CH 7: Vitamin E Supplements

•May contain natural or synthetic sources, check the label. •Synthetic form (dl-) not the same as natural form (d-). •Need 40 to 50 percent more of synthetic to match natural form.

CH 8: Magnesium Supplementation

•Mg may help reduce blood pressure as part of a healthful diet, such as the DASH diet (rich in Mg and K, low in Na). •Probably only helps physical performance if correcting a deficiency. •More research is needed. •Excessive intakes may result in nausea, vomiting, and diarrhea. •Increased serum Mg levels in persons with kidney disorders may lead to coma and death.

CH 8: Mineral Supplements: Exercise and Health

•Mineral supplements are marketed for both health and sport performance. •Mineral supplementation may enhance health or exercise performance if a mineral deficiency is corrected. •Mineral supplements do not appear to affect health or exercise performance in individuals whose mineral status is adequate.

CH 7: Vitamin K Functions

•Needed for the formation of four compounds that are essential for blood clotting. •May enhance function of osteocalcin, a protein with an important role in strengthening bones.

CH 7: Folate Supplementation—Physical Performance

•No apparent effect on endurance performance. •Folate supplementation may increase serum folate, but has no effect on VO2 max, maximum treadmill running time, peak lactate levels, or running speed at the lactate anaerobic threshold.

CH 7: Vitamin K Prudent Recommendations

•No available evidence supports vitamin K supplementation as a means to improve the health status of the average individual or to improve performance in athletes. •Individuals desiring to use vitamin K supplements should do so only under the guidance of a physician.

CH 7: Vitamin B12 Functions

•Part of coenzyme critical to formation of D N A. •Works with folate; both have important roles in red blood cell formation. •Formation of myelin sheath on nerve fibers. •Metabolism of homocysteine.

CH 7: Folate Deficiency—Physical Performance

•Pernicious anemia could impair delivery of oxygen to tissues and specifically impair performance in aerobic endurance events.

CH 8: Food Sources of Copper (1)

•Seafood, meats, nuts, beans, whole-grain products, and foods containing chocolate. •May be found in drinking water; in particular, soft water may leach it from copper pipes.

CH 8: Chromium Supplementation

•Some studies show improved glucose control in diabetics, but not in those without diabetes. •Overall, little to no effect on body composition in sedentary individuals, individuals engaged in various forms of exercise training, or athletes engaged in training for their sport. •Does not appear to benefit various forms of exercise performance.

CH 8: Sports Anemia

•Sports anemia is not a true anemia. •May occur during the early phases of training or when the magnitude of training increases drastically. •Plasma volume expands, diluting R B C concentration. •Increased plasma volume is beneficial and helps maintain optimal oxygen delivery.

CH 9: What are values for normal blood pressure and high blood pressure, a.k.a. hypertension?

•Systolic pressure: Blood pressure during heart contraction. •Diastolic pressure: Blood pressure at rest. Blood pressure category Systolic and Diastolic blood pressure values (mmHg) Normal < 120 and < 80 Elevated 120 to 139 and < 80 Stage 1 hypertension 130 to 139 or 80 to 89 Stage 2 hypertension 140 to 180 or 90 to 120 Hypertensive crisis > 180 or > 120

CH 7: Vitamin/Mineral Supplements

•Talk with your healthcare provider. •Check the Daily Value; look for 100 percent or less of DV for each vitamin. •Purchase from reputable sources. •Avoid added ingredients.

CH 8: Iron Deficiency in Athletes

•The prevalence of iron deficiency is likely to be higher in athletes, especially in younger female athletes, than in healthy sedentary individuals. •One recommendation is to screen for iron deficiency in female athletes.

CH 7: Niacin Prudent Recommendations

•Unless recommended under the treatment of a physician, niacin supplements are not recommended for a physically active individual consuming a balanced diet. •Excessive intake may actually impair certain types of athletic performance and elicit adverse health effects.

CH 7: Fat-Soluble Vitamins

•Vitamins A, D, E, and K. •Soluble in fat, but not in water. •Found in foods with some fat content. •Stored in the body. •Several may be manufactured in the body. •Excessive intake may be toxic.

CH 7: Vitamin D Functions (2)

•Works in conjunction with several other hormones, particularly parathormone, secreted by the parathyroid gland. •Important in muscle function. •Associated with chronic, non-skeletal diseases, including cardiovascular disease, hypertension, multiple sclerosis, arthritis, infection, autism, and certain cancers. •Taking vitamin D supplements is associated with decreased mortality.

CH 8: Should physically active individuals take mineral supplements?

•You can get the minerals you need via your diet. •Mineral deficiencies to the point of adversely affecting exercise performance are rare. •Minerals in excess may be harmful over time. •Certain athletes may benefit from supplementation. •Consult a health professional, sport nutritionist. •If you do not consult a health professional, try to stick with a one-a-day vitamin/mineral supplement with no more than 50 to 100 percent of the R D A for any mineral.

CH 7: Vitamin E Supplementation—Physical Performance

1,200 I U daily for 6 weeks improved VO2 max, reduced blood lactic acid during submaximal exercise, and increased aerobic endurance in sedentary subjects at altitudes of 5,000 and 15,000 ft. •More recent studies have supported these findings in athletes. May prevent R B C damage and peroxidation for athletes competing in high-smog areas. No apparent ergogenic effect at sea level or for marathon runners.

CH 9: How can I reduce the hazards associated with exercise in a hot environment?

1.Check temperature and humidity; slow pace. 2.Exercise in the cool of the day. 3.Exercise in the shade if possible. 4.Wear sports clothing designed for the heat. 5.Run with wind first, against wind later. 6.Hyperhydrate. 7.Drink cold fluids periodically. 8.Replenish your water daily; weigh yourself. 9.Replenish lost electrolytes (sodium, potassium). 10.Avoid excess dietary protein intake. 11.Avoid ephedrine. 12.Check your responses to caffeine. 13.Avoid alcohol. 14.Use caution if overweight, sedentary, aged. 15.Know signs and symptoms of heat illnesses. 16.Do not exercise if ill or with fever. 17.Check your medications; some may impair skin blood flow. 18.Acclimatize yourself to exercise in the heat.

CH 8: Osteoporosis (2)

10 million American adults over the age of 50 have osteoporosis, and an addition 34 million are at risk due to low bone mass. •More common in women than men. Over 1.5 million people experience an osteoporosis-related fracture each year. •Following a serious fracture, nearly a third or more of women and men die due to accompanying illnesses within a year.

CH 8: Introduction

25 elements essential in humans. •H, O, C, S, and N that make up carbohydrate, fat, protein, water. •Major minerals. •Trace minerals. Minerals compose less than 4 percent of an average person's body weight. Deficiencies. •May occur with some minerals. •Females and young athletes at risk. Supplementation. •Some individuals may benefit.

CH 8: Major Functions of Phosphorus in Humans

80 to 90 percent in bones and teeth as calcium phosphate. Organic forms: •Phospholipids help form cell membranes. •Essential component of most B vitamins. •Component of high energy compounds ATP, PCr. •Phosphorylation of glucose for glycolysis. •Part of 2,3-B P G in red blood cell to facilitate release of oxygen to the muscle tissues.

CH 8: Major Functions of Calcium

98 percent in the skeleton, gives strength. 1 percent used in tooth formation. 1 percent used in metabolism. •Muscle contraction. •Enzyme activation. •Helps regulate nerve impulse transmission, blood clotting, hormone secretion. •Cell membrane potential. Calcium balance. •Calcium intake needs to match calcium losses.

CH 9: Heat Stroke 2

A C S M defines exertional heat stroke as a rectal temperature greater than 40°C (104°F) accompanied by symptoms or signs of organ system failure Symptoms: •Confusion. •Disorientation. •Aggressiveness. •Blank stare. •Apathy. •Irrational behavior. •Staggering gait. •Delirium. •Convulsions. •Unresponsiveness. •Coma.

CH 9: Water Requirements

A I established for water under normal environmental temperatures and activity levels. A I for adults age 19 and over. •Males: 3.7 liters (3.9 quarts). •Females: 2.7 liters (2.9 quarts).

CH 8: Iron Deficiency

A leading worldwide risk factor for disability and death. •Estimated 2 billion people, mostly women and children in developing countries. •Impairs brain development in children. •Contributes to reduced capacity for work in adults. Main factor in Western world is inadequate dietary intake. •10 to 19 percent of females 12 to 49 years of age in the United States are iron deficient; only 1 percent of males.

CH 8: Functions of Selenium

A part of selenoproteins, enzymes such as glutathione peroxidase, an antioxidant enzyme. •Helps protect cell membranes, such as in red blood cells, from damaging oxidation. Selenoproteins may serve as biomarkers for diabetes and several forms of cancer.

CH 9: Electrolytes: What is an electrolyte?

A substance in solution that conducts an electric current. Electrolytes in the human body (Na+, Cl-, K+, Ca++, Mg++) and others •Electrical currents in nerves and muscles. •Activate enzymes to control metabolism.

CH 9: Heat Cramps

According to Minetto and colleagues, a plausible mechanism for cramp formation, first postulated by Schwellnus, is spinal-mediated hyperexcitability of motor neurons resulting from fatigue or other changes in afferent input. Exercise-associated muscle cramps. •May occur at any temperature, but more common in hot, humid conditions. Theories: •Cause still remains a mystery. •Fatigue and abnormal spinal control of motor neurons. •Salt losses—oral or intravenous saline can stop cramping. Prevention. •Consume salt solutions at first sign of muscle twitches. •EnduroLytes®; GatorLYTES®.

CH 9: What dietary modifications may help reduce or prevent hypertension?

Achieve and maintain a healthy body weight. Reduce or moderate sodium intake. Consume a diet rich in fruits, vegetables, and low-fat, protein-rich foods with reduced saturated and total fat. •D A S H diet. Moderate alcohol consumption. Be cautious with dietary supplements.

CH 8: Food Sources of Heme Iron

Animal foods: meat (beef), chicken, fish. •Greater bioavailability than nonheme iron. •About 35 to 55 percent of iron in meat is heme iron.

CH 8: Zinc Supplementation (1)

Beneficial. •May improve growth and development of zinc-deficient children. •May significantly reduce diarrhea mortality in children. •When combined with other nutrients, may be useful to help prevent age-related macular degeneration. •Possible role to reduce body copper levels and protect against cognition decline associated with Alzheimer's disease.

CH 9: What are some sound guidelines for maintaining water balance during exercise?

Benefits of proper hydration. •Decrease fluid loss. •Reduce cardiovascular strain. •Enhance performance. •Prevent some heat illnesses. Techniques. •Skin wetting. •Hyperhydration. •Rehydration.

CH 7: Vitamin D Supplementation—Health Effects (1)

Bone health: •Combined with calcium appears to help decrease fractures in postmenopausal women. •May also lower the risk of fractures in the elderly by increasing muscle strength and preventing falls. Cancer: •Epidemiological studies show reduced risk of colorectal cancer with vitamin D and calcium intake. •Prospective studies are equivocal, but some find reduced cancer risk; research is ongoing.

CH 8: What minerals are essential in human nutrition?

Calcium (Ca) Chloride Magnesium (Mg) Phosphorus (P) Potassium (K) Sodium (Na) Sulfur (S)

CH 8: Calcium and Cardiovascular Disease

Calcium may be involved in cardiovascular disease in several ways. •Calcification of blood vessels. Current research findings are uncertain. A meta-analysis reported increased risk of myocardial infarction and stroke. However, research has been criticized for various shortcomings, and large-scale randomized research is recommended in help provide some definitive answers.

CH 8: Calcium and Bone Health

Calcium supplements. Exercise. Hormone replacement or nonhormonal drug therapy. Osteoporosis in sports. •The Female Athlete Triad.

CH 9: Heat Exhaustion

Causes: •Dehydration. •Inadequate salt replacement. Symptoms: •Fatigue and weakness. •Rapid pulse. •Headache, nausea, vomiting, unsteady walk, muscle cramps, chills or goose bumps. •Rectal temperature < 104°F. Generally resolves with body cooling and fluids.

CH 7: Thiamin Functions

Central role in the metabolism of carbohydrates. •Part of a coenzyme needed to convert pyruvate to acetyl-CoA for entrance into the Krebs cycle. Essential for normal functioning of the nervous system and energy derivation from muscle glycogen.

CH 7: Vitamin B6 Functions

Coenzyme for protein metabolism; also involved in carbohydrate and fat metabolism. Functions with more than 60 enzymes: •Synthesis of dispensable amino acids. •Conversion of tryptophan to niacin. •Formation of neurotransmitters in the nervous system. •Incorporation of amino acids into body proteins, such as hemoglobin, myoglobin, and oxidative enzymes. Involved in the breakdown of muscle glycogen as well as gluconeogenesis.

CH 9: Exercise Performance in the Heat: Effect of Environmental Temperature and Fluid and Electrolyte Losses

Compensated heat stress. •Individuals are able to continue exercising because heat losses balance heat production and the core temperature does not increase excessively. Uncompensated heat stress. •Individuals are unable to continue exercising because heat production exceeds heat losses and exhaustion eventually occurs.

CH 8: Major Functions of Chromium

Component of the glucose-tolerance factor associated with insulin in the proper metabolism of blood glucose. Enhances the action of insulin, allowing glucose to enter cells. •Important for carbohydrate, fat, and protein metabolism. Helps maintain blood glucose levels, promotes glycogen formation in the muscles, and helps promote muscle tissue synthesis.

CH 7: Niacin Functions

Component of two coenzymes: •Nicotinamide adenine dinucleotide NAD+ —important in glycolysis and the Krebs cycle as well as fatty acid and amino acid metabolism. •Nicotinamide adenine dinucleotide phosphate (N A D P) is involved in fat metabolism by promoting fat synthesis in the body, which may block release of free fatty acids from adipose cells. Important for both aerobic and anaerobic energy processes.

CH 7: How effective are the multivitamin supplements marketed for athletes?

Contemporary research indicates that such supplements, consumed for substantial periods, are not ergogenic for the athlete on a balanced diet. Prudent recommendations: •Those involved in weight-control sports with limited caloric intake might consider taking a simple one-a-day supplement with no more than 100 percent of the R D A for the essential vitamins and minerals. •"Athletes should consider making better food choices and the daily use of a low-dosed multivitamin supplement."

CH 9: Regulation of Body Temperature:What is normal body temperature?

Core temperature. •Internal temperature. •Normal range: 97 to 99°F (36.1 to 37.2°C). •Typical oral temperature: 98.6°F = 37°C. Shell temperature. •Skin and underlying tissues. •May vary with ambient temperature.