1. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Chapter 15 The Cardiovascular System

2. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Cardiovascular System Components Heart: Pump Arteries, Arterioles: Distribution system Capillaries: Exchange vessels Veins: Collection and return system

3. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

4. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition The Heart Myocardium –Striated lattice-like network –Functions as a unit

5. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Functions of the Heart Functions of right side –Receive blood returning from body –Pump blood to lungs for gas exchange Functions of left side –Receive oxygenated blood from lungs –Pump blood into systemic circulation

6. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

7. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition The Arterial System Aorta  Arteries  Arterioles Vessels have endothelial tissue, smooth muscle, and connective tissue.

8. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

9. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Blood Pressure Pressure generated by the pumping action of the heart and the resistance of the blood vessels BP = Cardiac output × Total peripheral resistance

10. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Blood Pressure Systole –Contraction phase Diastole –Relaxation phase

11. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

12. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

13. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Blood Pressure Measurement Auscultation method –Listen for Korotkoff sounds. –Use a stethoscope and sphygmomanometer.

14. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Mean Arterial Pressure MAP = Diastolic BP + [0.333 (Systolic − Diastolic)] Reveals information regarding workload of the heart

15. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Capillaries Microscopic vessels 7 – 10  m in diameter Contain 6% of total blood volume Walls contain one layer of epithelial cells Skeletal muscles have a dense capillary network. Myocardium has an even denser network.

16. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Blood Flow in Capillaries Precapillary sphincters regulate flow. Capillaries open and flow increases during exercise.

17. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

18. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

19. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Venous Return One-way valves prevent back flow. Veins serve a capacitance role. –At rest, ~ 65% of blood is on the venous side of the system.

20. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Varicose Veins When one-way valves become defective, blood pools. Usually occurs in surface veins –Less musculature to help compress vessels –Occurs most frequently in legs Phlebitis –Severe varicose veins with inflammation

21. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Venous Pooling Muscle pump –Prevents pooling and edema –Directs blood back towards the heart

22. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Hypertension Chronically elevated blood pressure > 140 / 90 mm Hg Imposes a strain on the CV system It is a prevalent disorder.

23. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Effective Treatment Medications Regular physical activity Weight loss Stress management Decreased sodium intake Decreased alcohol consumption

24. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition BP Response to Exercise Resistance exercise –Straining compresses vessels. –Peripheral resistance increases. –Blood pressure increases in an attempt to perfuse tissues.

25. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Steady-Rate Exercise Systolic pressure increases with increases in workload. –There is a linear relationship between workload and systolic BP. Diastolic pressure remains fairly constant.

26. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

27. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition BP Response to Upper-Body Exercise Resistance to flow is increased with upper-body exercise. Smaller vessels in upper body compress more easily. Care is required for individuals with heart and valve diseases.

28. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition BP in Recovery Following endurance exercise, there is a hypotensive response. BP temporarily falls below normal resting values. Regular exercise may help control moderate hypertension.

29. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition The Heart’s Blood Supply Coronary circulation –Right and left coronary arteries branch off the upper ascending aorta. –RCA supplies predominantly the right atrium and ventricle. –LCA supplies the left atrium and ventricle and a small portion of the right ventricle.

30. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition

31. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Myocardial O 2 Use At rest, myocardium extracts ~ 70 – 80% available O 2. During exercise, flow must increase to meet O 2 demand. –Flow may increase 4 – 6 times.

32. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Effects of Impaired Blood Supply Impaired flow usually results in angina pectoris. If flow is severely reduced, myocardial infarction may result.

33. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Rate-Pressure Product: An Estimate of Myocardial Work Rate-Pressure Product or Double Product RPP = SBP × HR Is a commonly used measure of myocardial work

34. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Myocardial Metabolism Myocardium has a significantly higher mitochondrial density compared with skeletal muscle. This allows the heart to utilize –Glucose –Fatty acids –Lactate

35. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition Myocardial Metabolism Endurance exercise training increases the ability to use lactate and fatty acids for fuel. Decrease reliance on CHO

36. Copyright © 2007 Lippincott Williams & Wilkins.McArdle, Katch, and Katch: Exercise Physiology: Energy, Nutrition, and Human Performance, Sixth Edition