بسم الله الرحمن الرحيم

1. بسم الله الرحمن الرحيم

2. Exercise physiology • Objectives: • Exercise as external stresses • Body response to exercise. • Adaption to long term exercise. • Measurement of some physiological parameters during exercise.

3. The musculoskeletal system and exercise

4. Types of muscle fibers: Fast twitchSlow twitch Diameter. Larger in diameter --------- Enzymes releasing 2-4 time more active energy Number of capillaries -------------- far more than fast fibers Type of the exercise short time exercise endurance (second or minute) (hours) Mitochondria and -------------- much more myoglobin than fast fibers “Heredity differences”

5. % of fast and slow twitch fibers in average man and in different types of sports.

6. Strength power and endurance: Strength: is the maximum contractile force by the muscle, depend mainly on the size and measured by (kg /cm2). Power: is the total work den by the muscle per unit period of time. Endurance : is the final measure of muscle performance, and depend upon the glycogen content of the muscle

7. Type of diet and muscle endurance

8. The muscle metabolic system in exercise 1- The phosphate system: Adenosine triphosphate (A.T.P) (Adenosine PO3 ~ PO3 ~ PO3-) Each mol.. 7300 calories. (for 3 seconds)

9. Creatin phosphate (creatin~ Po3) each bond 10.300 calories ( 8-10 seconds)

10. 2- The glycogen–Lactic acid sys. glycolysis • Glucose E+ pyruvic acid. +02 energy used for resynthesize of 4 A.T.P molecules In absence of 02 - 02 • Pyruvic acid lactic acid (1.3 – 1.6 minutes).

11. +O2CO2+H2O+energy 3- The aerobic system. In presence enough amount of O2 Glucose Fatty acids Amino acids

12. The three important metabolic systems that supply energy for exercising muscle

13. Duration for each metabolic system

14. Energy system used in various sports.

16. Recovery after exercise: • Recovery is the time pass between the end of exercise and return back to the resting parameters. O2 O2 • Lactic acid pyruvic acid E+CO2+H2O • Energy from the aerobic system used for reconstitute of A.T.P, cr~ p also glycogen in lactic acid system.

17. O2 debt • It is the O2 which was not supplied during the exercise and supplied during recovery. • Used for oxidation of accumulated lactic acid and resynthesize A.T.P and C.P. • It’s value is the difference between the of O2 consumed during recovery period and the amount of O2 consumed during a similar period of rest.

18. The steady state (second wind) • On starting exercise athletes suffer from dyspnea and discomfort. • Dyspnea disappears after some time due to increase respiratory and circulatory functions to proved sufficient O2. (steady state or second wind)

19. Relation between exercise and:a. Work loads. b. O2 uptake. c. Blood lactate.

20. Respiration and exercise The aim of respiratory changes during exercise is: • supply extra O2 needed for the exercise. • wash out extra CO2 from exercised muscle. • adjust acid / base balance. • avoid an increase in body temperature.

21. O2 consumption and pulmonary ventilation in exercise Measurement of Pulmonary ventilation “spirometer”

22. Pulmonary ventilation • Minute respiratory volume. = tidal volume x respiratory rate/min. = 500 ml x 12 breath /min. = 6000 ml/min = 6L/min.

23. Anatomical dead space = 150 ml. • Alveolar ventilation: = respiration rate x the amount of air enter the alveoli with each breath = 12 x (500 – 150) = 12 x 350 = 4200 ml/min

24. Maximal voluntary ventilation (M.V.V): is the maximal volume of air that can be breathed per minute using fastest and deepest respiratory effort Normally= 80 – 160 L/mint for male. = 60 – 120 L/minute for female. average 100L/minute

25. Breathing reserve (B.R.): It’s the difference between pulmonary ventilation during rest and maximum voluntary ventilation B.R = M.V.V _ M.R.V. = 100 _ 6 = 94 L/min.

26. Mechanisms of breathing reserve: • Impulses from the cerebral cortex. • Impulses from the hypothalamus. • Impulses from the contracting muscle joint and ligaments. • Impulses from the limbic system. • Impulses from the chemoreceptor's (Pco2, Po2, H+). • Increases venous return. • Increases body temperature.

27. Regulation of breathing during exercise

28. Pulmonary ventilation during:a. Rest. b. Exercise. c. Recovery.

29. Gas transport during exercise. O2 transport: • O2 content: is the amount of O2 in 100 ml blood • O2 carrying capacity of the blood: • 1gm HB carries 1.34 ml O2 • total amount of HB is 15 gm. /100ml . Therefore The maximum O2 carrying capacity of the blood = 15 X 1.34 = 20 ml/ 100ml blood.

30. Percent of saturation of HB with O2 O2 content = x 100 O2 capacity

31. The relation between O2 pressure and content: • For dissolved O2 it is linear. • for oxygenated HB it is S- shaped or sigmoid shape.

32. Normal O2 HB dissociation curve

33. Shift of the curve to the right: Means that HB gives more O2 to the tissues even at a high PO2 (decreases affinity of HB to O2) as in increases of: • H+ (acidity). • PCO2. • 2-3 (DPG) diphosphoglyceride. • temperature. Therefore during exercise the curve is shifted to the right.

34. Shift of the curve to the left Means that HB gives less oxygen to the tissues even under low pressure (increase affinity of HB to O2) as in: • decreases H+ (alkalosis). • decreases arterial PCO2. • decrease 2-3 DPG. • carbon monoxide poisoning.

35. O2 HB dissociation curve during exercise

36. Effect of exercise on respiratory mechanisms A- changes in ventilation “at the lung”: • PO2 in pulmonary capillaries falls from 40 to 25 mmHg. • blood flow /minute increased from 5.5-20L/min. • the total amount of O2 entering the blood increases from 250 ml/min. to 4000 ml/min. • the amount of CO2 removed increases from 200ml/min to 8000ml/min.

37. B- changes at the tissue level: • during exercise PO2 at the tissue and venous blood may fall to zero. • more O2 diffuses to the tissues “ increases extraction ratio up to 95%” • capillary bed is dilated. • more CO2 added to the blood. “shift of O2 D. curve to the right”

38. Fatigue: Inability to performs the exercise in spit of existence of the stimuli. causes: • depletion of the chemical transmitters • accumulation of metabolites. • depletion g muscle glycogen. • Ischemia. • accumulation of P. factor. • accumulation of tissue fluid in the muscle.

39. Cardiovascular system and exercise

40. Circulatory changes during muscular exercise: • blood flow for resting muscles (600-900ml/min.). • during exercise 1200 - 20000 ml/min. Mechanisms of increase muscle blood flow: • increases metabolites (H+, Co2,K, kinins ete …) • rise of temperature. • excitement and sympathetic activity. • adrenalin secretion. • hypoxia. (nitric oxide).

41. The effect of muscular exercise on the C.V.S. either generalor local effects: A- general effects. I- increase heart rat 70 - 140-180 B\min. by: • impulses from higher centers (C.C., respiratory center and hypothalamus) • rise of body temperature. • chemical changes (H+, PCO2, PO2). • increases venous return. • impulse from contracting muscle.

42. II- increases venous return about 5-6 folds. By: • arteriolar dilatation • muscle contraction “peripheral hearts” • respiratory pump. • increases of venomotor • contraction of blood reservoirs.

43. III- cardiac output: Increase from 5L/min 25 or 35 L/min. C.O.P= heart rate x stork volume (V.R).

44. IV- Blood pressure: A.BL.P= C.O.P x peripheral resistance. • increases in C.O.P increases the systolic blood pressure. • fall in peripheral resistance (by V .D. of exercising muscle) lower the diastolic Bl.P or may remain unchanged.

45. B) Local effects: I- local blood flow to much increase by arteriolar and capillary dilation. II- tissue fluid and lymph. To much increases due to capillary dilatation.

46. Regional distribution of blood flow in different body systems during exercise

47. Thank you