Chapter 10 Nutrients, Physical Activity, and the Body’s Responses

1. Chapter 10Nutrients, Physical Activity, and the Body’s Responses Nutrition: Concepts & Controversies, 12e Sizer/Whitney

2. Introduction • Physical activity and nutrition • Needs • Energy-yielding nutrients • Vitamins and minerals • Results • Regulation of energy-yielding nutrients • Body composition • Daily calorie allowance

3. Fitness • Depends on physical activity or exercise • Movement, muscle contraction, & energy expenditure • Benefits • Chronic disease • Longevity • Disease resistance • Numerous other benefits

4. Physical Activity Guidelines for Americans

5. Intensity of Physical Activity

6. The Essentials of Fitness • Components of fitness • Adaptations • Athletes • Muscle power • Agility • Reaction times • Fatigue

7. How Do Muscles Gain in Size and Strength? • Activity choices • Overload • Balance of activity and rest • Work different muscle groups • Muscles need rest • Replenish and adapt • Specific training • Hormones and muscle growth

8. What Are the Benefits of Resistance Training? • Progressive weight training • Prevent and manage chronic disease • Muscle strength & size, power, or endurance • Resistance and repetitions • Appearance • Mobility and bone loss • Slows loss of physical mobility • Maximize and maintain bone mass

9. How Does Cardiorespiratory Training Benefit the Heart? • Enhances capacity • Heart, lungs, and blood • Enhances efficiency • Delivery of oxygen • VO2 max • Removal of wastes • Blood lipid profile • Heart disease risk

10. The Active Body’s Use of Fuels • Fuels • Mixtures • Vary • Excess postexercise oxygen consumption (EPOC) • High intensity activities • Cardiac output • Fuel usage

11. Delivery of Oxygen by the Heart and Lungs to the Muscles

12. Glucose Use and Storage • Muscle glucose • Retains glycogen for own use • Liver glucose • Glycogen and endurance • High-carbohydrate diets

13. The Effect of Diet on Physical Endurance

14. Activity Intensity, Glucose Use, and Glycogen Stores • Energy stored as glycogen • Anaerobic use of glucose • Quick energy • Muscle glycogen reserves • Aerobic use of glucose • Energy from glucose and fatty acids • Lactate • Anaerobic activity • Muscle size and strength

15. Glucose and Fatty Acids in Their Energy-Releasing Pathways in Muscle Cells

16. Activity Duration, Glucose Use, and Glycogen Stores • Glucose use • Duration of activity • Intensity of activity • Blood glucose and activity • Dietary strategies • High carbohydrate diet daily • Consume glucose during activity • Consume carbohydrate shortly after exercise

17. Fat and Physical Activity • Body fat as fuel for activity • Sources of fat • Importance of strength training • Fat in the athlete’s diet • Performance • Omega-3 fatty acids • Intensity and duration • Degree of training

18. Protein for Building Muscles and for Fuel • Muscle protein synthesis • Up to two days after activity • Intensity and pattern of muscle contraction • Muscle cells only build proteins as needed • Dietary protein • Supplements • High-quality proteins • Fuel for physical activity • Factors that regulate protein use

19. Nutrients of Concern • Vitamin E • Physical activity creates more free radicals • Benefits of vitamin E supplements • Studies are conflicting • Interference with absorption • Iron • Deficiency impairs performance • Groups at risk for deficiency • Sports anemia

20. Water Losses During Physical Activity • Water losses • Breathing and sweating • Dehydration • Sweat and temperature regulation • Heat stroke • Potentially fatal • Reduce risk • Hypothermia • Symptoms

21. Fluid and Electrolyte Needs During Physical Activity • Hydrate and rehydrate • Thirst signal • Hourly sweat rate • Water • Endurance athletes • Electrolyte losses and replacement • Minerals • Sports drinks vs. regular diet

22. Sodium Depletion and Water Intoxication • Replenishing electrolytes • Crucial time • Hyponatremia • Differs from dehydration • Heat cramps • Sodium

23. What Do Sports Drinks Have to Offer? • Fluid • Glucose • Sodium and other electrolytes • Psychological edge

24. Ergogenic Aids • Caffeine • Endurance vs. high-intensity activities • Adverse effects • Diuretic • Carnitine • Nonessential nutrient • Chromium picolinate • Carbohydrate and lipid metabolism • Safety concerns

25. Ergogenic Aids • Creatine • Hypothesized benefits • Confirmed effect • Weight gain • Conjugated linoleic acid (CLA) • Not worth their price • Sodium bicarbonate • Unpleasant side effects

26. Ergogenic Aids • Amino acid supplements • Maximum gains • Essential amino acids in system prior to physical work • Best source • Food • Reasons against supplements

27. Ergogenic Aids • Whey protein and other protein supplements • By product of cheese making • Timing of protein intake • Complete meal replacers • Fall short of ‘complete’ nutrition • Risk of dental caries • Nutritional uses • Pregame meal • Between-meal snack

28. Hormone Preparations • Anabolic steroid hormones • Illegal and dangerous • Steroid alternative supplements • Herbal or insect sterols • Prohormones • Androstenedione • DHEA • Drugs posing as supplements

29. Physical Risks of Taking Steroid Hormone Drugs