Final Review and Assessment of Profile and Nutritional Health – FSM 159 Nutrition - 30 points After you have completed your IProfile analysis and your personal iProfile questions - you must now review

Chapter 10 Nutrition, Fitness, and Physical Activity Food, Physical Activity, and Health • Both food and physical activity are necessary components of optimal health. • Fitness: set of attributes related to the ability to perform routine physical activities without undo fatigue. Physical Activity Reduces the Risk of Chronic Disease • Physical activity includes both planned exercise and daily activities (i.e. cleaning, yard work, etc.) • Regular exercise can prevent or delay the onset of chronic condit ions: cardiovascular disease, hypertension, type 2 diabetes, breast and colon cance r, and bone and joint disorders (i.e. weight -bearing exercise stimulates bones to become denser and stronger and therefore reduces the risk of osteoporosis). • Physical activity reduces overall mortality, regardless if person is lean, normal weight, or obese. • Physical activity improves mood and self -esteem and increases vigor and overall well - being. • Increases muscle mass, strength and endurance. • Improves flexibil ity and balance. • Reduces sleeplessness, depression , stress, and anxiety. • Benefits of exercise can overcome some of the health risks of carrying excess body fat. • Exercise stimulates the release of endorphins, boosting mood and helping with relaxation, pain tolerance, and appetite control. Physical Activity Makes Weight Management Easier • Exercise increases both energy needs and lean body mass. • The more energy you expend, the more food you can eat and still maintain a healthy weight. • Exercise is an essential component of any weight -reduction program: o Increases energy needs. o Promotes loss of body fat. o Slows the loss of lean tissues that occurs with energy restriction. o Reported to reduce risk of stress -induced weight gain. The Four Com ponents of Fitness • Fitness defined by endurance, strength, flexibility, and body composition. • Fitness achieved by regular exercise. • Overload principle: the concept that the body adapts to the stresses placed on it. Cardiorespiratory Endurance • Cardiorespiratory endurance: the efficiency with which the body delivers to cells the oxygen and nutrients needed for muscular activity and transports waste products from cells. o Aerobic exercise: endurance exercise that increases heart rate and uses oxygen to provide energy as ATP. ▪ Examples: jogging, bicycling, and swimming. ▪ Decreases resting heart rate: the rate at which the heart beats when the body is at rest. o Aerobic capacity: the maximum amount of oxygen that can be consumed by the tissues during exercise. ▪ Also called maximal oxygen consumption or VO 2max. Muscular Strength and Endurance o Muscular strength: the a bility to perform tasks such as pushing or lifting . ▪ Example: lifting a gallon of milk off top shelf of refrigerator with one hand . o Muscular endurance: the ability of a muscle group to continue repetitive muscle activity . ▪ Example: shoveling snow . o Muscle strengthening : activities that are specifically design ed to increase muscle strength, endurance and size. ▪ Also called strength -training exercise or resistance -training exercise. ▪ Examples: weight lifting and calisthenics. o Hypertrophy: the building of larger, stronger muscles. “Use it or lose it”. Flexibilit y • Range of motion, how far you can bend and stretch muscles and ligaments . o Example s: static or dynamic stretching exercises . Body C omposition • Proportion of muscle to fat in the body. o Affected by fitness. o Affected by age and gender. o Desirable amount of body fat: ▪ Young adult women: 21 – 32% of total weight. ▪ Young adult men: 8 – 19% of total weight. Physical Activity Recommendations • Public health guidelines to reduce risk of chronic diseases : o At least 150 minutes of moderate -intensity physical activity or 75 minutes of vigorous -intensity aerobic activity each week or an equivalent combination of both. • Greater health benefits: exercising more vigorously or for a longer duration. • Examples: o Moderate exercise: walking 3 miles in about an hour or bicycling 8 miles in about an hour. o Vigorous intensity : jogging at a rate of 5 miles per hour or faster or bicycling 10 miles per hour or faster. o Muscle -strengthen ing activities: 2 or more days per week. o Even a small amount of exercise is better th an none. What to Look for in a Fitness Program • A complete fitness program includes: o Aerobic exercise for cardiovascular conditioning. o Stretching exercises for flexibility. o Muscle -strengthening exercises to increase muscle strength and endurance and maintain or increase muscle mass. • The program should be integrated into an active lifestyle that includes a variety of everyday activities, enjoyable recreational activities, and minimum amount of ti me spent in sedentary activities. • Moderate or vigorous aerobic activity most days of the week. o Maximum heart rate: the maximum number of beats per minute that the heart can attain. o Aerobic zone: heart rate 60 – 85% of maximum heart rate. • Structure fitness program based on needs, goals, and abilities. • Muscle -strengthening exercises : 2 – 3 days per week on nonconsecutive days. • Flexibility exercises: 2 – 7 days per week. Time spe nt in stretching does not count towards meeting aerobic or strength training guidelines. Creating an Active Lifestyle • Steps to starting and maintaining an exercise program: o Find an exercise you enjoy. o Set aside a time that is realistic and convenient. o Find a place that is appropriate and safe. • Suggestions for starting and maintaining an exercise program: o Start slowly. Set specific, attainable goals. Once you have met them, add more. o Make your exercise fun and convenient. o Stay motivated. o Keep your exercise safe. ▪ Overtraining syndrome: a collection of emotional, behavioral, and physical symptoms that occurs when the amount and intensity of exercise exceeds an athlete’s capacity to recover. Fueling Activity • ATP: high -energy compound used to fuel activity. Made from carbohydrate, protein, and fat. • Anaerobic metabolism: production of ATP in the absence of oxygen. o Produces ATP rapidly. o Must use glucose as the fuel. o Produces lactic acid, which can be used as a fuel for aerobic metabolism. • Aerobic metabolism: production of ATP with oxygen. o Can use any fuel: carbohydrate, protein, or fat. o Slower, but more efficient than anaerobic metabolism. Exercise Duration and Fuel Use • Instant energy: ATP first few seconds then we use creatine phosphate . o Creatine phosphate: a compound stored in muscle that can be broken do wn quickly to make ATP. • Short -term energy: Anaerobic metabolism after about 15 seconds . o Limited amount of glucose leads to limited ability to produce ATP fast and efficiently. • Long -term energy: Aerobic metabolism after 2 -3 minutes . o ATP produced at a slowe r rate, but much more efficient. o Able to use fatty acids and amino acids as a source of fuel. o Exercising at a low to moderate intensity, fatty acids become the primary fuel source. • Protein as a fuel for exercise: not considered a major source of energy. o Mo re protein is used if there is not enough total energy intake, more protein is consumed than needed, or if endurance exercise is involved. What a Scientist Sees: The Fat -Burning Zone • Which workout will help you to lose the most weight: 30 -minute in the cardio zone or 30 -minute in the fat burning zone? Why? Exercise Intensity and Fuel Use • Exercise intensity determines the contributions of carbohydrate, protein, and fat as fuels for ATP production. o At rest and low -to -moderate intensity exercise: aerobic m etabolism predominates: fatty acids are an important fuel source. o As exercise intensity increases: proportion of energy supplied by anaerobic metabolism increases: glucose becomes the predominant fuel. o During exercise, the total amount of energy expended i s greater than the amount expended at rest. • Fatigue: inability to continue an activity at an optimal level. o Occurs more quickly with high -intensity exercise than with lower -intensity exercise. o “Hitting the wall ” or “bonking” : an overwhelming feeling of fat igue: depletion of glycogen. o Lactic acid build -up is one of many metabolic changes associated with muscle fatigue. Fitness Training and Fuel Use • Regular exercise to improve fitness causes physiological changes in the body. o The heart becomes larger and str onger so that the amount of blood pumped with each beat is increased. o Aerobic training causes physiological changes in the cardiovascular system that incre ases the delivery of oxygen to cells. o The total blood volume and number of red blood cells expands, i ncreasing the amount of hemoglobin, so that more oxygen can be transported. o In the muscle, there is an increase in the ability to store glycogen and an increase in the number and size of muscle -cell mitochondria. Energy and Nutrient Needs for Physical Act ivity • Major difference between the nutritional needs of a serious athlete and those of a casual exerciser: amount of energy and fluid required , and the quantity and timing of their protein intake . Energy Needs • Amount of energy expended depends on the intensity, duration, and frequency of the ac tiv ity and environmental conditions under which the exercise is performed . o The more intense the activity, the more energy it requires. o The more time spent exercising, the more energy required. • Energy intake to op timize body weight and composition : body weight and composition can affect exercise performance. o Achieving an increase in muscle mass: combination of increased energy intake, adequate protein intake, and strength -training exercise to pro mote an increase in lean tissue rather than fat. o Dieting to maintain an unrealistically low weight may threaten health and performance. ▪ Weight loss should be done in advance of the competitive season to prevent calorie restriction from affecting performance. ▪ Gener al guidelines: reduce energy intake by 200 to 500 Calories/day, increase activity, and change the behaviors that led to weight gain. • Relative energy deficiency in sport (RED -S): occurs when athletes do not consume enough to support their energy expenditure , so they do not have enough energy available to maintain their health and support body functions. o Example: female athlete with low energy availability may progress to RED -S, changing hormone levels affecting menstrual cycle and lead to low bone mineral density. ▪ Previously known as “female athlete triad” but is now recognized as a part of RED -S. o Can affect male or female athletes . o Can alter many other aspects of physiology that impair health and exercise performance. o These athletes are vulnerable to eatin g disorders. ▪ Example: anorexia and bulimia . o More common in a thletes involved in weight class sports: risk of unhealthy weight -loss practices to compete in a lower weight class. ▪ Example: wrestling, boxing ▪ Severely restrict energy intake, or dehydrating themselves through vigorous exercise, fluid restriction, wearing of vapor -impermeable suits, use of hot environment to increase sweat loss. May also vomit or use diuretics and laxatives. ▪ Can be dangerous and fatal. ▪ Can impair performance and negatively affect heart and kidney function, temperature regulation, and electrolyte balance. Carbohydrate, Fat, and Protein Needs • Carbohydrate: 3 to 1 2 g of carbohydrate/kg of body weight per day. • Fat: 20 - 35% of total calories; same as that of the general population. • Protein: 15 – 20% of total calories. o 1.2 to 2.0 g protein/kg of body weight. Vitamin and Mineral Needs • Exercise increases the amounts of many vitamins and minerals used both in metabolism and in repairing tissues after exercise. • Exercise may increase losses of some micronutrients. o Nutrients of key concern: iron, calcium, Vitamin D, and some antioxidants. • Iron o Prolonged training may increase iron requirements because iron loss in feces, urine, and sweat increases. o Foot -strike hemolysis: breaking of red blood cells due to the contraction of large muscles or impact in events such as running. o Reduced iron stores: common in athletes. ▪ Females at particular risk due to menstrual blood loss . ▪ Ina dequate iron intake for both genders . ▪ Reduced absorption from GI tract that occurs several hours after exercise. o Sports anemia: an adaption to training that does not seem to impair the delivery of oxygen to tissues. o Iron needs of athletes: 30 to 70% higher than the general population. • Calcium and Vitamin D o Needed for bone health o Low calcium intake occurs from disordered eating, restricted energy intake or in those that avoid dairy products. o Risk of low bone mineral density and stress fractures is increased by RED -S. o Adequate vitamin D intake needed to regulate calcium absorption and metabolism. • Antioxidant Nutrients o Dietary antioxidants: vitamin C, vitamin E, β -carotene, and selenium. o Little evidence that supplementation with antioxidants improves performanc e. Water and Electrolyte Needs • Exercise increases water needs: increases loss from sweat and evaporation. • Meeting the needs of thirst, may not be enough for an athlete. • Dehydration: risk is greater in the hot. Can occur in the cold. o May be difficult to drink enough to compensate for losses. • Dehydration and heat -related illnesses: conditions including: heat cramps, heat exhaustion, and heat stroke, that can occur due to an unfavor able combination of exercise, hy dration status, and climatic co nditions. o Heat cramps: involuntary muscle spasms that occur during or after intense exercise. ▪ Caused by an imbalance of electrolytes at the muscle cell membranes. ▪ Can occur when water and salt are lost during extended exercise. o Heat exhaustion: water loss causes blood volume to decrease so much that it is not possible both to cool the body and to deliver oxygen to active muscles. ▪ Characterized by a rapid but weak pulse, low blood pressure, disorientation, profuse sweating, and fainting. o Heat stroke: most se rious form of heat -related illness. ▪ Occurs when core body temperature rises above 105 0F, causing the brain’s temperature -regulatory center to fail. ▪ The individual does not sweat. ▪ Characterized by: elevated body temperature; hot, dry skin; extreme confusion; and unconsciousness. Requires immediate medical attention. o As the severity of dehydration increases, exercise performance declines. • Hyponatremia: Low blood sodium. o Caused by excessive sweating and fluid replacement with plain water. ▪ Sodium conce ntration in the blood decreases. ▪ Water moves into body tissues by osmosis, causing swelling. ▪ Fluid in the lungs interferes with gas exchange. ▪ Fluid accumulation in the brain causes disorientation, seizure, coma and death. o Risk can be reduced by consuming sodium -containing sports drinks during long - distance events. ▪ Increasing sodium intake several days prior to competition. ▪ Avoiding acetaminophen , aspirin, ibuprofen, and other nonsteroidal anti - inflammatory drugs. Food and Drink to Optimize Perfo rmance • For competitive athletes, when and what they eat and drink before, during, and after exercise are as important as a balanced overall diet. • Type and amount of fluids and foods eaten at these times may give or take away extra seconds that can mean victory or defeat. What to E at and Drink Before Exercise • Maximizing glycogen stores: larger glycogen stores allow exercise to con tinue for longer periods . o Glycogen supercompensation or carbohydrate loading: a diet and exercise regimen designed to increase muscle glycogen stores beyond their usual capacity. ▪ Rest for 3 to 4 days prior to competition. ▪ Consume a very high -carbohydrate diet: 10 to 12 g of carbohydrate/k g of body weight per day . ▪ Beneficial for endurance athletes. ▪ No benefit and provides disadvan tages for those exercising for less than 90 minutes. The P recompetition M eal • Beverages and food consumed should provide plenty of fluid and carbohydrate and not cause GI distress. • 1-4 hours before exercise: Eat 300 -500 calories. o High carbohydrate 1 -4 g/kg body weight o Protein 10 -20% of total C alories o Fat 10 -25% of total C alories o Low fiber • 2-4 hours before exercise: Drink 5 -10 mL/kg. • “Lucky” foods may add a psychological advantage. What to E at and Drink During Exercise • For adequ ate hydration drink 1.5 to 3.5 cups ( 400 -800 mL ) of fluid per hour for duration of the exercise. • Exercise less than 45 minutes: no food needed and drink plain water . • Exercise greater than 45 minutes : need carbohydrate to maintain glucose and delay fatigue. o For exercise lasting more than about 1 hour, consume a sodium -containing beverage or snack to reduce risk of hyponatremia, improve glucose and water absorption, and stimulate thirst. o Example: sports drink containing carbohydrate and sodium . • Exerci se 45 to 75 minutes: small amount of carbohydrate from food or beverages consumed per hour . • Exercise 60 to 150 minutes: 30 -60 g of carbohydrate per hour . o Example: large banana or an energy bar. • Exercise greater than 150 minutes: 90 g of carbohydrate per hour . o Examples: sports drink, solid -food snack, or carbohydrate gel with water. What to E at and Drink After Exercise • Replenish lost fluid, electrolytes and glycogen and provide protein for building and repairing muscle tissue. • Restore hyd ration; replace each kilogram of body weight lost with 1.25 to 1.5 L of fluid (approximately 2 .5-3 cups/pound lost). • For athletes competing over consecutive days, for glycogen replacement consume carbohydrate 1 .0-1.2 g/kg/hour for 4 -6 hours . • To stimulate muscle protein synthesis and provide amino acids needed for protein synthesis and repair consume high -quality protein 0.3 g/kg within 2 h ou rs after exercise; consume balanced meals including protein for 24 hours after exercise . Thinking It Through: A Case Study on Snacks for Exercise • Examine the advantages and disadvantages of energy bars. Ergogenic Aids • Ergogenic aid: a substance, appliance, or procedure that improves athletic performance. o Weigh the health risks against the potential benefits. Vitamin and Mineral Supplements • Many promises about the benefits of vitamin and mineral supplements are extrapolated from the biochemical functions of these micronutrients. o B vitamins promoted to enhance ATP production because of their roles in muscle energy metabolism. o Vitamin B 6, B 12, folic acid , and iron are promoted for aerobic exercise because they are involved in the transport of oxygen to exercising muscle. o Vitamin E, vitamin C, and selenium are promoted because of their antioxidant functions. o Chromium and vanadium are marketed to increase lean body m ass and decrease body fat. o No evidence that supplements improve athletic performance. o These micronutrient supplements are only needed if the athlete is deficient in one or more of them. Supplements to Build Muscle • Ergonomic aids are used to increase muscl e size and strength. • Protein supplements are marketed with the promise of enhancing muscle strength and growth. • Protein needs can be met without supplements by eating high -quality protein foods. o Eat foods such as lean meat, eggs, milk, or soymilk after exe rcise to optimize protein synthesis. • Protein supplements should only be used to optimize exercise recovery not to replace nutrient -dense whole foods. • β-hydroxy -β-methylbutyrate (HMB): claims to increase strength and muscle growth and improves muscle recovery. o Recent studies: some studies found that supplementation in trained athletes have a beneficial effect on body composition and aerobic capacity. • Anabolic steroids: synthetic fat -soluble hormones that mimic testosterone and are used to increase muscle strength and mass. o Accelerate protein synthesis. o Taken in conjunction with exercise and an adequate diet, they can cause increases in muscle size and strength. o Extremely d angerous side effects. o Prohibited by International Olympic Committee, National Collegiate Athletic Association ( NCAA ), and other sporting organi zations . • Think Critically : Anabolic Steroids o Question: Why does anabolic steroid use promote muscle development but cause the testes to shrink? • Growth hormone: increases muscle pr otein synthesis. o It has not been shown to have ergogenic benefits. o Prolonged use can cause heart dysfunction, high blood pressure, and excessive growth of some body parts. o Is on the World Anti -Doping Agency list of banned substances. Supplements to Enhance Performance in Short, Intense Activities • Bicarbonate and β -alanine : acts as a buffer in the body. o Supplementing it is thought to neutralize acid which preserves muscle function , delay s fatigue and improve s performance. ▪ Bicarbonate p ossible side effects: abdominal cramps and diarrhea. ▪ β-alanine : safety has not been studied, use caution • Creatine: nitrogen containing compound, found primarily in muscles, is used to make creatine phosphate. o Higher levels of creatine phosphat e provide more quick energy for short -term muscular activity . o Shown to improve performance in short -duration high -intensity intermittent exercise . ▪ Example: sprinting, weight lifting. o Increase in strength , power, and muscle mass when combined with strength training . o For healthy adult: up to 3 g per day. o Do not take if at risk for kidney disease, consult a physician before use. o May cause weight gain and GI discomfort. Supplements to Enhance Endurance • Carnitine supplements: substances that increase the utilization of fat during exercise. o Enough carnitine is made in the body to ensure efficient use of fatty acids. o Found in red meat and dairy products. o Supplements have not been shown to increase endurance. • Medium -chain triglycerides (MCT): composed of fatt y acids with carbon chains of 8 to 10 carbons. o Can be absorbed directly into the blood, causing blood fatty acid levels to rise and increasing availability of fat as a fuel for exercise. o Research has not found that sup plementation increases enduranc e. • Caff eine: stimulant found in coffee, tea, some soft drinks, and in pill form. o Enhances the release of fatty acids, sparing the use of glycogen and delaying fatigue. o Taking caffeine up to an hour before exercise has been shown to improve endurance. o Athletes una ccustomed to caffeine respond well verses those who consume it routinely. o Also increases vigilance and alertness. o May cause GI upset. o Excess caffeine before competition used to be prohibited by the International Olympic Committee but now it is not restrict ed. • Erythropoietin (EPO): hormone used to enhance endurance. o Naturally produced by the kidneys and stimulates cells in the bone marrow to differentiate into red blood cells. o Can enhance endurance by increasing the ability to transport oxygen to the muscle s. o Can cause production of too many red blood cells and can lead to excessive blood clotting, heart attacks, and strokes. o Banned in 1990 after it was linked to the deaths of more than a dozen cyclists. DEBATE: Energy Drinks for Athletic Performance? • Question: Should energy drinks be used as ergogenic aid s? Is drinking them a safe way to improve your game? Diet, Supplements , and Performance • Bottom line with ergogenic aids is to do no harm . • Impact on performance is small compare d to benefit of a well -planned healthy diet . • Consider risks before using these products.