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Exercise physiology

Exercise physiology. Exercise physiology. Recommended literature:. Wilmore, J. H., & Costill, D. L. (1994). Physiology of sport and exercise. Champaign, IL: Human Kinetics.

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Exercise physiology

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  1. Exercise physiology

  2. Exercise physiology Recommended literature: • Wilmore, J. H., & Costill, D. L. (1994). Physiology of sport and exercise. Champaign, IL: Human Kinetics. • Åstrand, P.-O., Rodahl, K., Dahl. H. A., & Strømme, S. B. (2003). Textbook of Work Physiology: Physiological Bases of Exercise (4th ed.). Champaign, IL: Human Kinetics. • Brooks, G. A., Fahey, T. D., & White, T. P. (1995). Exercise physiology: human bioenergetics and its applications (2nd ed.). • Mountain View, CA: Mayfield Publishing Company.Sharkey, B. J. (1990). Physiology of fitness. Champaign, IL: Human Kinetics.

  3. Exercise => causes the changes in human body A) Acute response to one bout of exercise – e.g. ↑ heart rate (HR), ↑ body temperature (HR) B) Chronic adaptation to repeated bouts of exercise - e.g.↓ HR at restand ↓ HRat exercise (same intensity) Muscle activity requires energy. During exercise are energy demands enhanced. - decrease of ATP, increase of ADP Muscle contractile work = transforming chemical energy into kinetic (mechanical) energy

  4. Energy metabolism A) Anabolism - creation of reserve (carbohydrate, fat, proteins) B) Catabolism – release of energy (glycolysis,lipolysis) hydrolisis ATP ADP + P + E phosphorylation ATP – adenosine thriphosphate - common energy “currency” ADP – adenosine diphosphate P - phosphate E - energy (e.g. for muscle contraction)

  5. Energy metabolism • Energy sources • 1] Polysaccharides simple sugars glucose (glycogen) • 2] Fats (triglycerides) fatty acids (FFT) and glycerol • 3] Proteins amino acids

  6. Energy metabolism Glucose is the only one that can be broken down anaerobically and aerobically as well. Anaerobic glycolysis blood plasma membrane cell plasma G G Glycogen (GG) G – 6 - P 2 ATP (G) 3 ATP (GG) lactic acid pyruvic acid

  7. Energy metabolism Aerobic glycolysis pyruvic acid (pyruvate) cell plasma mitochondrial membrane mitochondrion Acetyl CoA NADH (nicotinamide adenine dinucleotid) and FADH Citric acid cycle CO2

  8. Energy metabolism oxidative phosphorylation – in mytochondrion (electron transport chain) NADH + O2 + 3ADP 3ATP + NAD + H2O 1 NADH=3 ATP FADH + O2 + 2ADP 2ATP + FAD + H2O 1 FADH=2 ATP

  9. Energy metabolism From one molecule G GG Anaerobic glycolysis 2 ATP 3 ATP Aerobic glycolysis 36 ATP 36 ATP Total glycolysis 38 ATP 39 ATP Glycogen reserves are in muscle cells (500g) and in liver (100 g). - From 1.500 to 2.500 kcal. 1 calorie (cal) is the amount of energy increases the temperature of 1 gram H2O from 14.5ºC to 15.5ºC.

  10. Energy metabolism Fat - triglyceride = FFA (free fat acids) + glycerol in subcutaneous tissue (141 000 kcal). Adipose tissue Glucose metabolism NADH triglyceride FFA + Glycerol Hormone-sensitive lipase Beta oxidation Acetyl CoA NADH Citric acid cycle CO2

  11. anaerobic Energy metabolism aerobic proteins Glucose FFA and/or Acetyl CoA lactic acid Citric acid cycle NADH and FADH Electron transport chain plasma membrane

  12. Energy metabolism Anaerobic metabolism • only carbohydrate • increases when lack of O2 • lower amount of ATP, but very fast and huge in short time • production of lactic acid Anaerobic metabolism • carbohydrate, fats, proteins • enough of O2 • higher amount of ATP, but slower Note: proteins are not very important sources of energy (5-10%). Amino acids are preferabely used as a building matters for muscles hormones, etc.

  13. Energy metabolism hydrolisis ATP ADP + P + E phosphorylation ATP is only the one immediate source of energy for muscles work, etc. Other ways of the creation (phosporylation): ATP + P ADP + CP(creatine phosphate) ATP + AMP ADP + ADP

  14. Zones of energy supply Anaerobic free of lactic acid Anaerobic with lactic acid Aerobic free of lactic acid

  15. Total energy expenditure - s trváním pokles (?Havlíčková et al, 1991)

  16. Dominant way of restoration of ATP is oxidative phosphorylation Acute reaction of the body (neurohumoral controlled) for increase in supply of working muscles by energy sources and O2 • increase glucose in blood (from liver glycogen) • activation of FFA (activation of hormone sensitive lipase)

  17. CO2 RQ = O2 Sources of energy by increasing exercise intensity energy expenditure kJ/min RQ carbohydrates = 1 1 g = 4,1 kcal RQ fats = 0,7 glycogen 1 g = 9,3 kcal fats glucose (Hamar & Lipková, 2001) exercise intensity % VO2max

  18. CO2 RQ = O2 Sources of energy by increasing exercise intensity CO2 - expired O2 - inspired RQ – respiration quotient – ratio between CO2 and O2 RQ carbohydrates = 1 = 1 l CO2/1 l O2 more O2 RQ fats = 0,7 = 0.7 l CO2/1 l O2 RQ normal (mixed) = 0,82

  19. Lipids (FFA) • more energy (1 g = 9,3 kcal) • need more O2 (EE = 4,55 kcal) • use while enough of O2 (at rest, low intensity of exercise)

  20. Lipids (FFA) • more energy (1 g = 9,3 kcal) • need more O2 (EE = 4,55 kcal) • use while enough of O2 (at rest, low intensity of exercise) – energetic equivalent – shows amount of energy released while applied 1 liter of O2 on carbohydrate or on FFA EE

  21. Lipids (FFA) • more energy (1 g = 9,3 kcal) • need more O2 (EE = 4,55 kcal) • use while enough of O2 (at rest, low intensity of exercise) Carbohydrates • less energy (1 g = 4,1 kcal) • need less O2 (EE = 5,05 kcal) • use while not enough of O2 (higher intensity, and anaerobically as well) • small amount is always use at rest

  22. CO2 RQ = O2 Sources of energy by increasing exercise intensity energy expenditure kJ/min RQ carbohydrates = 1 1 g = 4,1 kcal RQ lipids = 0,7 glycogen 1 g = 9,3 kcal fats glucose (Hamar & Lipková, 2001) exercise intensity % VO2max

  23. Mechanism of energy release in dependence on intensity VO2max Anaerobic threshold NOTE: Ideal model Aerobic threshold REST aerobic anaerobic

  24. Wasserman scheme of transport O2 a CO2 Ventilation Muscle work Transport O2 and CO2 O2 Mito- chon- drion AIR lungs muscles cardiovascular s. CO2 (Wasserman, 1999)

  25. The more O2 is delivered to working muscle, the higher aerobic production of energy (ATP) Better endurance performance, smaller production of lactic acid while the same speed of run, longer lasting exercise, etc.

  26. Wasserman scheme of transport O2 a CO2 Ventilation Muscle work Transport O2 and CO2 O2 Mito- chon- drion AIR lungs muscles cardiovascular s. CO2 (Wasserman, 1999)

  27. Fick equation: VO2 = Q × a-vO2 × HR SV VO2 – oxygen consumption[ml/min] Q – cardiac output[ml/min] a-vO2 – arteriovenous oxygen difference SV – stroke volume[ml] HR – heart rate [beet/min]

  28. a-vO2 – arteriovenous oxygen difference

  29. DA-V – arteriovenous oxygen difference • difference in the oxygen content of arterial and mixed venous blood • the value tells about the amount of oxygen used by working muscles • depends on the muscle ability to absorb and use the O2 from blood (perfusion, amount of capillary, mitochondrion, number of working muscles, etc.) - at rest 50 ml O2 from 1L of blood - during exercise 150-170 ml O2 1L of blood (100 ml krve is saturated by 20 ml O2) (1L of blood is saturated by 200 ml O2)

  30. 1 L of blood is saturated by 200 ml O2 To ensure during exercise: ↑BF (breathing frequency, rate) - from 12-16 breath/min up 60 (70 and more) ↑TV (tidal volume) • from 0.5 Lup 3 L Minute ventilation (VE) = BF × TV - at rest 6 L/min = 12 × 0.5 - during maximal exercise 180 L/min = 60 × 3

  31. . VO2 = Q × DA-V Q = HR × SV rest: SEDENTARY 4,9 L= 70 beet/min × 70 ml rest: TRAINED 4,9 L= 40 beet/min × 120 ml In work: increase of HR and SV - ↑ Q • SV increases till HR 110 – 120 beet/min • (from 180 beet/min decreases) • - HRmax = 220 - age

  32. . VO2 = Q × DA-V Q = HR × TV rest: SEDENTARY 4,9 L= 70 beet/min × 70 ml rest: TRAINED 4,9 L= 40 beet/min × 120 ml rest: VO2 = 4,9 L of blood × 50 ml O2 VO2 = 245 ml/min human (70kg): 245 : 70 = 3,5 ml O2/kg/min (1MET)

  33. . VO2 = Q × DA-V Q = SF × SV Max. exercise:SEDENTARY 20 L = 200 beet/min × 120 ml Max. exercise:TRAINED 35 L= 200 beet/min × 175 ml

  34. . VO2 = Q × DA-V Max. exercise: SEDENTARY: VO2max= 20 L of blood × 157 ml O2 VO2 max= 3140 ml/min 70 kg human: 3140 : 70 = 45 ml O2/kg/min (13 METs)

  35. . VO2 = Q × DA-V Max. exercise: TRAINED: VO2max= 35 L of blood × 170 ml O2 VO2 max= 5950 ml/min 70 kg human: 5950 : 70 = 85 ml O2/kg/min (25 METs)

  36. Definition and explanation of VO2max • VO2max • is maximum volume of oxygen that by the body can consume during intense (maximum), whole body exercise. • - expressed: • - in L/min • - in ml/kg/min • - METs 1 MET - resting O2 consumption (3.5 ml/kg/min) 10 METs = 35 ml/kg/min 20 METs = 70 ml/kg/min

  37. Importance of VO2max Higher intensity of exercise Higher energy demands (ATP) Increase in oxygen consumption Lower VO2max = less energy = worse achievement

  38. Importance of VO2max During endurance activity is being ATP resynthesized mainly aerobically from lipids and carbohydrates. The moreis O2supplied toworking muscles, the more higher is an amount of aerobically produced energy. It meanshigher speed of running, latest manifestation of fatigue, etc. It shows the capacity for aerobic energy transfer.

  39. Average values of VO2max Average (20/30 years) not trained: - female 35 ml/kg/min - male 45 ml/kg/min Trained: to85 ml/kg/min (cross-country skiing) Decreases with age. Lower in female.

  40. Average values of VO2max

  41. Limitation factors of VO2max Ventilation Muscle work Transport O2 and CO2 O2 AIR lungs muscles cardiovascular s. CO2 (Wasserman, 1999)

  42. Limitation factors of VO2max 2) Muscles – is limitation factor 1) Lungs – no limitation factor 3) Cardiovascular system – dominant limitation factor

  43. Wasserman scheme of transport O2 a CO2 Ventilation Muscle work Transport O2 and CO2 O2 Mito- chon- drion AIR lungs muscles cardiovascular s. CO2 (Wasserman, 1999)

  44. VO2max = Qmax × DA-Vmax On increase of VO2max participate: • Increase of DA-Vmax – shares on increase about 20% • Increase of Qmax – shares aboout 70 - 85%

  45. Influence of the gender, health condition, age Heredity – the increase of VO2max by training only to max. 25% Gender – in female lower muscle mass, lover hemoglobin Age – decrease of active body mass, activity of enzymes…

  46. CO2 RQ = O2 Sources of energy by increasing exercise intensity energy expenditure kJ/min RQ carbohydrates = 1 1 g = 4,1 kcal RQ lipids = 0,7 glycogen 1 g = 9,3 kcal fats glucose (Hamar & Lipková, 2001) exercise intensity % VO2max

  47. VO2max [ml/kg/min] 45 AT 50-60% VO2max 3,5 exercise intensity (speed, load,etc.)

  48. AT (aerobic threshold) - exercise intensity, when „exclusive“ aerobic covering ends. • exercise intensity, from which anaerobic covering starts and lactate is being produce • level of lactate: 2 mmol/L of blood

  49. VO2max [ml/kg/min] plateau 45 AnT 70-90 % VO2max AT 50-60 % VO2max 3,5 exercise intensity (speed, load,etc.)

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