Health Advantages of Regular Exercise

THIRD EDITION HUMAN PHYSIOLOGY AN INTEGRATED APPROACH Dee Unglaub Silverthorn, Ph.D. Chapter 25 Integrative Physiology III: Exercise PowerPoint® Lecture Slide Presentation by Dr. Howard D. Booth, Professor of Biology, Eastern Michigan University Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings About this Chapter • Overview of how major systems are involved in the metabolism for skeletal muscle contraction • How the extreme activities of exercise disrupt homeostasis • Focus on how the circulatory & respiratory systems integrate their responses to exercise demands • How exercise impacts health Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Integration of Metabolism: Review of Roles of Systems in Muscle Contraction • Reactants • Transport • Conversions • Energy produced • Contractions • Respiration • Excretion • Endocrine • Nervous Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Integration of Metabolism: Review of Roles of Systems in Muscle Contraction Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 25-1: Energy metabolism in skeletal muscle Energy for Skeletal Muscle Contraction • ATP & ADP • Phosphocreatine • Aerobic paths • Anaerobic paths • (glycolytic metabolism) Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Sustaining Muscle contractions: ATP Sources/Time • Phosphocreatine: Short bursts at maximal effort • Anaerobic: Intermediate duration intense effort • Aerobic: Long duration at reduced effort Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 25-2: Speed of ATP production compared with ability to sustain maximal muscle activity Hormonal regulation of Energy Source for ATP Production • (Huge body reserves – glucose 2000 & FAAs 70,000 Kcal) • Exercise intensity • Glucose • Fatty acids Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Hormonal regulation of Energy Source for ATP Production • Metabolic Shifts • Glucagon • Cortisol • Epinep./NE • GH • (insulin) Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Hormonal regulation of Energy Source for ATP Production Figure 25-3: Use of carbohydrates and fats with increasing exercise Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Oxygen Consumption: Factors Sustaining or Limiting Exercise • O2 consumption:: to  exercise (measure w/Vo2 max) • Limiting factors: • O2 – cell availability, (O2 deficit) • O2 – transport to: mitochondria, to cell, to blood, or to lung Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Oxygen Consumption: Factors Sustaining or Limiting Exercise Figure 25-4: Changes in oxygen consumption during and after exercise Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Ventilation: Exercise Induced hyperventilation • Feed forward Reflex: CNS • Feedback reflexes: • Motor sensors • Joint movement • Muscle contraction • Chemo sensors • O2 & CO2 levels • Synchronized w/ cardiac output • Plasma: [O2], [CO2] & [ pH] Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Ventilation: Exercise Induced hyperventilation Figure 25-5: Changes in ventilation with submaximal exercise Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Respiratory Ventilation: Exercise Induced hyperventilation Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Figure 25-6: Changes in blood gas, partial pressures, and arterial pH with exercise Cardiovascular Response to Exercise • Cardiac output •  5 to 35 L/min • Rate  2-3 X • Blood distribution •  muscles to 88% of all blood •  other tissues (except brain) Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Cardiovascular Response to Exercise Figure 25-7: Distribution of cardiac output at rest and during exercise Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Balancing of Exercise: “Controlled Disruption” • Feed forward reflexes • Anticipate demand • Heart & lungs • Protective reflexes • Stretch damage • Temperature  • sweating •  peripheral • blood flow • redistribution • Blood pressure  constant Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Homeostatic Balancing of Exercise: “Controlled Disruption” Figure 25-8: Peripheral resistance and arterial blood pressure during exercise Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Health Advantages of Regular Exercise: Quality of Life •  Cardiovascular disease risks: heart attack, stroke, high BP •  blood pressure •  LDL & triglycerides •  HDL  risks for diabetes • [blood [glucose] •  obesity •  stress association •  immune function • (to a point) Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Health Advantages of Regular Exercise: Quality of Life Figure 25-9b: The effect of exercise on glucose tolerance and insulin secretion Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Health Advantages of Regular Exercise: Quality of Life Figure 25-10: Immune function and exercise Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Summary • Exercise challenges a range of many systems involved in metabolism to produce maximal energy from various nutrient sources • Phosphocreatine most quickly produces ATP for muscle contraction while anaerobic glycolysis is intermediate • Aerobic ATP production is needed for endurance exercise Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings Summary • Ventilation and cardiac rate and output undergo huge changes which are anticipated by feed forward reflexes and protected by other reflexes to keep BP and temperature in homeostatic • Exercise reduces risk factors in some most common health problems: heart disease, obesity , diabetes, and stress Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings