NTDT310 Exam 1 Study Guide PDF

Introduction to Nutrition, Healthful Nutrition, Introduction to Ergogenic Aids, and Human Energy What is nutrition? What does the science of nutrition include? ○ Nutrition: the science of food ○ Includes: digestion, absorption, transport, metabolism The six major classes of nutrients that are essent...

Introduction to Nutrition, Healthful Nutrition, Introduction to Ergogenic Aids, and Human Energy What is nutrition? What does the science of nutrition include? ○ Nutrition: the science of food ○ Includes: digestion, absorption, transport, metabolism The six major classes of nutrients that are essential for human nutrition ○ Macronutrients: carbohydrates, fats, proteins, ○ Micronutrients: minerals, vitamins ○ Water Differences between essential/non-dispensable vs non-essential/dispensable nutrients ○ Essential nutrients: nutrients that the body cannot produce and need to come from food ○ Non-essential nutrients: the body makes these nutrients and are not required from food AMDR for the three macronutrients ○ Carbohydrates: 45-65% of total daily calories ○ Fats: 20-35% of total daily calories ○ Proteins: 10-35% of total daily calories Physical Activity Guidelines for Americans ○ 150-300 minutes of moderate-intensity aerobic activity or 75-150 minutes of vigorous-intensity aerobic activity ○ 2 or more days of muscle-strengthening activities Physical activity vs physical fitness ○ Physical activity: involves any bodily movement caused by muscular contraction that results in the expenditure of energy Unstructured or structured ○ Physical fitness: a set of abilities individuals possess to perform specific types of physical activity Health-related fitness or sports-related fitness Ergogenic aids: what they are, how they may aid performance in sport ○ Techniques or substances that enhance sports performance ○ Enhance physical power, mental strength, or mechanical edge Classes of ergogenic aids and examples of aids that belong to each class ○ Mechanical, psychological, physiological, pharmacological, and nutritional Define metabolism ○ Represents the sum total of all physical and chemical changes that take place in the body Difference between anabolism vs catabolism ○ Anabolism: the building up process; complex body components are synthesized from basic nutrients ○ Catabolism: tearing down process; breakdown of body components into their simpler components Describe what the Calorie represents. The calorie content of each macronutrient ○ Represents the form of potential energy to be used by our bodies to produce heat and work ○ 1 gram of carb = 4kcal ○ 1 gram of protein = 4kcal Major energy stores in the human body (5). Sources with least and greatest storage capacity ○ Adenosine triphosphate (ATP): immediate energy source ○ Phosphocreatine (PCr) ○ Carbohydrates ○ Fats ○ Proteins Major human energy systems ○ ATP-PCr systems (phosphagen system) ○ Lactic acid system (anaerobic glycolysis) ○ Oxygen system (oxidative or aerobic system) Aerobic power (glycolysis) Aerobic capacity (lipolysis) Predominate energy system for a given exercise task ○ ATP-PCr: competitive weight lifting, 100m dash ○ Anaerobic glycolysis: high-intensity workouts lasting for 30-120 seconds ○ Oxygen system: low-intensity to moderate-intensity workouts lasting longer than a few minutes Strengths and limitations of each system ○ ATP-PCr: provides energy rapidly, limited energy supply ○ Anaerobic glycolysis: helps replace ATP, cannot be used directly as a source of energy for muscular contraction ○ Oxygen system: produces ATP in large amounts, produces it at a slower rate The crossover concept ○ Carbs to fat ○ At low-intensity exercise, fat is a major energy source ○ At high-intensity levels, carbs become the major energy source Total energy expenditure. Three major factors/components ○ The sum of basal metabolic rate, thermic effect of food, exercise activity thermogenesis, and non-exercise activity thermogenesis make up total daily energy expenditure ○ Factors: basal energy expenditure, thermic effect of food, physical activity energy expenditure Calorimetry: Strengths/limitations of each type ○ Measures heat production ○ Direct: bomb or room calorimeter ○ Indirect: based on O2 consumption and CO2 production Factors that influence energy expenditure requirements ○ Physical activity, diet, age, body composition, muscle mass… Carbohydrates and Protein For each macronutrient, understand: ○ Basic structures ○ Basic steps of metabolism ○ Major/primary functions ○ Storage forms (primary) ○ Ergogenic Aspects (requirements and use for different types of activity) ○ Broad exercise-related needs and recommendations How do the needs of an exercising individual differ compared to non-exercising individuals? Carbohydrates: Know the mono and disaccharides (what monosaccharides make up each disaccharide) ○ Monosaccharides: glucose, fructose, galactose ○ Disaccharide: maltose (glucose and glucose), lactose (glucose and galactose), sucrose (glucose and fructose) Effects of exercise on glucose uptake ○ Exercise causes GLUT-4 translocation, independent of insulin Three major energy sources of carbohydrates. Greatest energy storage source (most amount stored in terms of kcal)? ○ Blood glucose (20 kcal), liver glycogen (300-400 kcal), muscle glycogen (1,200-1,600 kcal) Importance of CHO intake before, during, and following exercise ○ Before: gives fuel to muscles ○ During: helps maintain blood glucose levels in prolonged events and enhance performance ○ After: replenish depleted muscle and liver glycogen What type and length of activities require carbohydrate intake during the exercise? ○ Moderate amount of intense training (2-3 h/day, 5-6 d/week): 5-8 g/kg/day ○ High volume intense training (3-6 h/day, 5-6 d/week): 8-10 g/kg/day Unique ability of carbohydrate vs protein and fat as an energy source during exercise ○ Carbs can be used anaerobically and aerobically ○ Can produce ATP for muscle contraction up to 3x more rapidly than fat Primary carbohydrate source for energy for exercise/performance ○ Muscle glycogen Relationship between exercise and fatigue, and relationship/role of carbohydrates (blood glucose and glycogen levels) in fatigue? ○ Exercise and fatigue: depletion of glycogen and decline of blood glucose levels during exercise results in fatigue Are pyruvate, lactate salts, or ribose supported with substantial evidence as effective ergogenic aids? ○ Pyruvate: lack evidence to support ergogenic effect on endurance performance ○ Lactate Salts: improves performance on high-intensity exercise, no data on sports or athletic performance ○ Ribose: research does not support the claim that it produces ergogenic benefits Potential benefit of CHO combinations (e.g., consuming glucose + fructose vs only glucose) ○ Combinations can result in oxidation rates up to 1.7 g/min compared to 1 g/min for single Potential ergogenic effects of carbohydrate loading ○ Carbohydrate loading: a dietary technique that promotes the increase in muscle and liver glycogen content to delay the onset of fatigue ○ Enhances performance in prolonged intermittent high-intensity exercises and prolonged aerobic endurance exercises Class of athletes who can benefit from carbohydrate loading, potentially ○ Athletes who sustain high levels of continuous energy expenditure for prolonged periods (long-distance runners, swimmers, cyclists, triathletes, cross-country skiers) Protein Understand what is meant by essential amino acid ○ Essential amino acids are from our diets ○ Histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, valine Understand what a high-quality/complete protein is and provide an example ○ High-quality proteins are foods that contain an adequate amount of all 9 essential AA ○ Animal proteins are high-quality (milk, eggs, whey) Know why deamination must occur ○ Undergoes deamination because the body cannot store excess nitrogen (NH2 will be removed from AA) What is formed from excess nitrogen? ○ Ammonia (NH2) Difference between MPS and MPB. When are you in net, negative, or positive protein balance? ○ MPS: process by which your body builds new muscle proteins, leading to muscle growth and repair ○ MPB: process where muscle proteins are broken down or degraded ○ MPS = MPB: net protein balance ○ MPS> MPB: positive protein balance ○ MPS< MPB: negative protein balance How do resistance training and dietary protein intake impact MPS and MPB? Role of leucine in MPS. Fast vs slow-acting proteins (whey vs casein) ○ MPS and MPB increase after resistance exercise; positive protein balance is best achieved when protein is consumed following exercise Protein use during resistance vs aerobic endurance training ○ Resistance training: does not increase protein oxidation, provokes muscle tissue catabolism ○ Aerobic training: minimal protein use compared to carb and fat, activates BCAA dehydrogenase, protein use may increase when body CHO stores decrease The main class of AA oxidized during exercise ○ BCAAs, specifically leucine By-products of protein metabolism during exercise that may contribute/be related to fatigue ○ Ammonia (nitrogen by-product, indicator of increased muscle AA breakdown) Consequences of insufficient protein intake ○ Athletes with insufficient protein intake will develop and maintain a negative nitrogen balance (indicates protein catabolism and slow recovery) Can lead to muscle wasting, injuries, illness, and training intolerance Importance of sufficient carbohydrate ○ Decrease reliance on protein during aerobic endurance exercise, reduce formation of ammonia, and allow for improved maintenance of normal protein status in the body Effects of exercise on protein metabolism ○ Produces a positive protein balance, decreases the formation of ammonia, prevents muscle protein damage, delays onset of muscle soreness, decreases protein catabolism, increases the ability of muscles to use protein as an energy source Positive effects of chronic training ○ Decreases protein catabolism Effects on metabolism and protein balance during the recovery period. Positive or negative protein balance, depending on dietary protein intake ○ Resistance exercise induces protein breakdown in exercised muscles, MPS is elevated for 24-48 hours after exercise Broad protein recommendations for athletes ○ Consume about 1.2-2.0 g/kg body weight per day, and consume protein with CHO before and after workouts Anabolic effects of insulin. Role in glucose and amino acid uptake into tissues ○ Skeletal muscle: increase glycogenesis, increase protein synthesis ○ Liver: increase glycogenesis, decrease glyconeogenesis ○ Adipose tissue: increase adipogenesis, decrease lipolysis ○ Increases glucose uptake Supplements with strong evidence for safety and efficacy: ○ Know the primary proposed ergogenic mechanism and ideal exercise type for use: Creatine Monohydrate: increases high-intensity exercise capacity, increases lean body mass during training Short bursts of high-intensity exercises Beta-alanine: increases muscle carnosine levels Exercises lasting 60-240 seconds Dietary Nitrate: increases plasma nitrate, reduces oxygen cost of exercise, enhances exercise performance, decreases blood pressure Endurance activities Calculations and Other Numbers Know how to convert pounds to kilograms and inches to meters Energy (kilocalorie) content of 1 gram of each macronutrient ○ Be able to convert from kcal to grams (and from grams to kcal) AMDRs for carbohydrate and protein ○ Be able to apply AMDR to generate a range of recommended intake of a macronutrient, based on total energy intake (example: if an individual consumes 2500 kcal per day, what is the AMDR for carbohydrate intake for this individual?) RDA for protein and how to calculate the RDA for an individual if provided the weight