© Cengage Learning 2016 Personal Nutrition, 9e Boyle | Long Nutrition, Physical Activity, and Fitness 11

© Cengage Learning Describe the health benefits of living a physically active lifestyle. 11.2Identify the four components of fitness and strategies to achieve overall fitness. 11.3Identify the factors that influence fuel use during physical activity. 11.4Describe the use of glycogen and body fat during physical activity. Chapter Objectives

© Cengage Learning Determine the protein needs of an athlete. 11.6Identify the factors that influence an athlete’s fluid needs and describe the recommended schedule of hydration before, during, and after exercise. Chapter Objectives

© Cengage Learning Describe how vitamins and minerals are used during physical activity 11.8Discuss the safety and efficacy of popular ergogenic aids used by athletes. Chapter Objectives

© Cengage Learning 2016 There is a two-way relationship between nutrition and fitness –Both are essential components of good health Recent health initiatives –Let’s Move! Initiative: focuses on child obesity –President’s Council on Fitness, Sports, and Nutrition 33 percent of adults exercise regularly 38 percent report no physical activity Introduction

© Cengage Learning 2016 Benefits of Physical Activity

© Cengage Learning 2016 The Physical Activity Guidelines for Americans –Moderate-intensity physical activity for 2-1/2 hours each week –OR– –Vigorous-intensity aerobic physical activity for 1 hour and 15 minutes each week –Note: greater benefits occur with more physical activity 11.1 Getting Started on Lifetime Fitness

© Cengage Learning 2016 Physical Activity Guidelines for Adults

© Cengage Learning 2016 Physical activity program for total fitness includes –Aerobic activity –Strength training –Stretching Physical activity time is a lifelong commitment 11.1 Getting Started on Lifetime Fitness

© Cengage Learning 2016 Seek medical advice if your profile includes risk factors for heart disease –Sedentary lifestyle –Family history of heart disease –Cigarette smoking –High blood pressure –High blood cholesterol (> 200 mg/dL) –Obesity (BMI ≥ 30) –Diabetes 11.1 Getting Started on Lifetime Fitness

© Cengage Learning 2016 Physical conditioning: a planned program of physical activity –Directed toward improving the function of a particular body system –Employs overload principal: causes the body to adapt and function more efficiently Ways to apply overload –Increase frequency –Increase intensity –Increase duration 11.2 The Components of Fitness

© Cengage Learning 2016 Strength: ability of the muscles to work against resistance Resistance training has many benefits –Build well-toned muscles needed for daily activities at work and during recreation –Strong muscles, tendons, and ligaments are less prone to injury –Helps with weigh loss: increases BMR 11.2 The Components of Fitness

© Cengage Learning 2016 Flexibility: range of motion –Depends on the elasticity of the muscles, tendons, and ligaments and on the condition of the joints –Tends to decrease with age –Improves in response to stretching and can be maintained by frequent stretching exercises 11.2 The Components of Fitness

© Cengage Learning 2016 Muscle endurance –Ability of a muscle to contract repeatedly within a given time without becoming exhausted –Impacts performance as an activity continues 18 th hole of a golf game Pedaling the last 10 miles of a 100-mile bike tour –Tests for specific muscles Number of sit-ups or push-ups in a specified time period 11.2 The Components of Fitness

© Cengage Learning 2016 Cardiovascular endurance –The heart is a muscle: responds to repeated demands by becoming larger and stronger –Best types of activities to improve cardiovascular endurance use large muscle groups, i.e., arms and legs –American College of Sports Medicine recommends cardiovascular conditioning At least five times a week Continuous 30 to 60 minutes each session 11.2 The Components of Fitness

© Cengage Learning 2016 Physical inactivity in sedentary societies –Directly contributes to multiple chronic health disorders Humans are genetically “programmed” to expect physical activity –Our bodies’ biochemistry and physiology was fine-tuned by and for conditions of life that existed more than 10,000 years ago Physical activity is a choice in fighting against life-threatening diseases Nutrition Action: Nutrition and Fitness—Forever Young

© Cengage Learning 2016 Health Consequences of Physical Inactivity

© Cengage Learning 2016 Metabolism: chemical process –Converts water, oxygen, and food to energy –Aerobic metabolism depends on oxygen –Anaerobic metabolism is performed without oxygen 11.3 Energy for Physical Activity

© Cengage Learning 2016 Aerobic and anaerobic metabolism –Moderate activity level allows the heart and lungs to supply the oxygen needed to perform aerobic metabolism –Muscle exertion with energy demand that outstrips the oxygen supply must also rely on anaerobic metabolism for energy –Types of anaerobic metabolism ATP-creatine phosphate (CP) system Glycolysis 11.3 Energy for Physical Activity

© Cengage Learning 2016 Aerobic exercise—exercise for the heart –Cardiovascular conditioning or the training effect Makes the heart stronger and increases its endurance Improves the endurance of the lungs and the muscles along the arteries and in the walls of the digestive tract Develops the muscles directly involved in the activity Increases blood volume 11.3 Energy for Physical Activity

© Cengage Learning 2016 How to calculate your target heart rate range 1.Estimate your maximum heart rate (MHR): subtract your age from Determine your target heart rate range: multiply your MHR by 55 percent and 90 percent to find your upper and lower limits Cardiovascular fitness goal –Work out at your target heart rate for 20 to 60 minutes 11.3 Energy for Physical Activity

© Cengage Learning 2016 Energy-producing pathways require –Oxygen –Two muscle fuels: glucose and fatty acids Oxygen is supplied by the lungs –Blood carries the oxygen to the muscles Muscles and to some extent, the liver, supply carbohydrate to the muscles Fatty acids come from fat inside the muscle and from released fat stores 11.4 Fuels for Physical Activity

© Cengage Learning 2016 Delivery of Oxygen by the Heart and Lungs to the Muscles

© Cengage Learning 2016 The Use of Glycogen and Body Fat for Energy during Physical Activity

© Cengage Learning 2016 Fuel Use and Duration/Intensity of Physical Activity Insert Figure 11-6 (line chart)

© Cengage Learning 2016 Fuel Use and Duration/Intensity of Physical Activity

© Cengage Learning 2016 Glucose use during physical activity –Glucose is stored in the liver and in the muscles in the form of glycogen (a long chain of glucose molecules linked together) Factors influencing glucose utilization –Length of exercise session –Degree of training –Amount of glycogen stored in the muscles before exercise 11.4 Fuels for Physical Activity

© Cengage Learning 2016 The Effect of Diet on Physical Endurance

© Cengage Learning 2016 Fat use during physical activity –Fatty deposits all over the body supply fat for muscles to burn during exercise –Oxygen must be present to burn fat Rule of thumb: If you can’t talk normally, you are burning more glucose than fat; if you can sing, you aren’t burning much of anything (so speed up). –Training impact Body is better at delivering fat to working muscles Muscles have increased ability to use fat 11.4 Fuels for Physical Activity

© Cengage Learning 2016 A total fitness routine is needed to enhance health Tips for sustaining a physical activity program 1.Check with your physician before starting 2.Find an exercise buddy 3.Do not overdo it, especially in the beginning 4.Do not focus on weight loss Eat Well Be Well: Use It and Lose It!

© Cengage Learning 2016 Optimal nutrient timing before or during and after resistance training –Can minimize muscle protein breakdown –Can optimize muscle growth and repair Refer to Table Protein Needs for Fitness

© Cengage Learning 2016 Water and fluid replacement drinks –Plasma volume (plasma): water in the blood Carries body heat to the skin where it can be dissipated –Water is lost through sweating and must be replaced –Athletes performing a vigorous activity must rehydrate before, during, and after exercise 11.6 Fluids and Physical Activity

© Cengage Learning 2016 Signs of hyponatremia –Severe headache –Nausea and vomiting –Muscle cramps –Bloating –Confusion –Seizure 11.6 Fluids and Physical Activity

© Cengage Learning 2016 Schedule of Hydration Before, During, and After Exercise

© Cengage Learning 2016 Water and fluid replacement drinks –Choice between water and a sports drink A preference for fitness enthusiasts A matter of performance for endurance athletes –Carbohydrates in sports drinks Provide an energy source for working muscles Help maintain blood glucose at an optimum level Help increase the rate of water absorption from the small intestine 11.6 Fluids and Physical Activity

© Cengage Learning 2016 Fluid Replacement Drinks

© Cengage Learning 2016 The vitamins –Are the links and regulators of energy- producing and muscle-building pathways B vitamins govern the energy-producing metabolism reactions –Needs are proportional to energy expenditure Eating five-plus fruits/vegetables per day –Helps athletes meet recommended intakes for the antioxidant nutrients 11.7 Vitamins and Minerals for Physical Activity

© Cengage Learning 2016 Exercise-Related Functions of Vitamins and Minerals

© Cengage Learning 2016 Exercise-Related Functions of Vitamins and Minerals

© Cengage Learning 2016 The minerals –Iron is crucial for hemoglobin and myoglobin, needed for oxygen delivery –Iron supplements should only be taken under medical supervision –Sports anemia is a temporary state An adaptation to physical training 11.7 Vitamins and Minerals for Physical Activity

© Cengage Learning 2016 Calcium, the bones, and exercise –Strength training encourages bone growth –Causes of stress fractures Unbalanced muscle development Bone weakness due to inadequate calcium intake Reduced estrogen concentration which leads to bone mineral loss –Preventing weak bones Consume adequate calcium and vitamin D throughout life 11.7 Vitamins and Minerals for Physical Activity

© Cengage Learning 2016 A well-balanced diet is key to peak performance Critical periods for the athlete –Training diet –Pre-competition diet The Savvy Diner: Food for Fitness

© Cengage Learning 2016 Planning the diet –Develop a diet rich in complex carbohydrates and low in fat –Choose foods to provide nutrients as well as calories –Eat six or eight meals each day rather than three or four meals The Savvy Diner: Food for Fitness

© Cengage Learning 2016 Training diet –Follow nutrition plans in the off-season –Finish meals at least 2 to 4 hours before training –A high-carbohydrate meal supports blood glucose levels during competition –Include plenty of fluids—two or more 8-ounce glasses of water or juice per meal—to ensure adequate hydration Consume adequate protein The Savvy Diner: Food for Fitness

© Cengage Learning 2016 Scientific evidence does not support –Claims of products providing a competitive advantage Ergogenic aids: substances that increase the ability to exercise harder –Refer to Table 11-8 –Perceived benefits may be due to the placebo effect FDA purports the need for better regulation of amino acid supplements 11.8 Spotlight: Athletes and Supplements—Help or Hype?

© Cengage Learning 2016 Human growth hormone –Not proven to cause weight loss Anabolic steroids can be dangerous Energy drinks or “preworkouts” –Are not properly formulated to enhance performance Glycogen-sparing effect of caffeine –Beneficial when exercising more than 1½ to 2 hours at a time 11.8 Spotlight: Athletes and Supplements—Help or Hype?

© Cengage Learning 2016 Questions to raise regarding an ergogenic aid 1.Is the promised action of the product based on magical thinking? 2.Does the promotion claim that “doctors agree” or “research has determined,” without clarification? 3.Does the promoter use scare tactics to pressure you into buying the product? 11.8 Spotlight: Athletes and Supplements—Help or Hype?

© Cengage Learning 2016 Questions to raise regarding an ergogenic aid (cont’d.) 4.Is the product advertised as having a multitude of different beneficial effects? 5.Is the product available only from the sponsor by mail order and with payment in advance? 6.Does the promoter use many case histories or testimonials from grateful users? 11.8 Spotlight: Athletes and Supplements—Help or Hype?