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 rest and ↓ HR at exercise (same intensity)

4. Změny vybraných parametrů

5. - decrease of ATP, increase of ADP
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 rest and ↓ HR at 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

6. 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)

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

8. 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
G – 6 - P
Glycogen (GG)
2 ATP (G)
3 ATP (GG)
pyruvic acid
lactic acid

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

10. 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

11. 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 (500 g) and in liver (100 g).
- From to kcal.
1 calorie (cal) is the amount of the energy increases the temperature of 1 gram H2O from 14.5ºC to 15.5ºC.

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

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

14. Energy metabolism Anaerobic metabolism Anaerobic metabolism
only carbohydrate
increases when lack of O2 and not enough time
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.

15. Energy metabolism ATP ADP + P + E
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 + C
ADP + CP(creatine phosphate)
ATP + AMP
ADP + ADP

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

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

18. 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)

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

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

21. more O2 Sources of energy by increasing exercise intensity
CO2 - expired
RQ =
CO2 O2
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

22. 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)

23. Lipids (FFA) EE – energetic equivalent
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) EE
– energetic equivalent
– shows amount of energy released while applied 1 liter of O2 on carbohydrate or on FFA

24. Lipids (FFA) Carbohydrates 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

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

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

27. 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.

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

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

30. a-vO2 – arteriovenous oxygen difference

31. 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 1 L of blood
- during exercise ml O2 1 L of blood
(100 ml krve is saturated by 20 ml O2)
(1 L of blood is saturated by 200 ml O2)

32. 1 L of blood is saturated by 200 ml O2
To ensure during exercise:
↑BF (breathing frequency, rate)
- from breath/min up 60 (70 and more)
↑TV (tidal volume)
from 0.5 L up 3 L
Minute ventilation (VE) = BF × TV
- at rest 6 L/min = 12 × 0.5
- during maximal
exercise 180 L/min = 60 × 3

34. . VO2 = Q × DA-V Q = HR × SV rest: SEDENTARY
4,9 L = 70 beat/min × 70 ml
rest: TRAINED
4,9 L = 40 beat/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 = age

35. . rest: VO2 = Q × DA-V VO2 = 4,9 L of blood × 50 ml O2
Q = HR × TV
rest: SEDENTARY
4,9 L = 70 beat/min × 70 ml
rest: TRAINED
4,9 L = 40 beat/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)

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

37. . VO2 = Q × DA-V Max. exercise: VO2max= 20 L of blood × 157 ml O2
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)

38. . VO2 = Q × DA-V Max. exercise: VO2max= 35 L of blood × 170 ml O2
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)

39. Definition and explanation of 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

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

41. Importance of VO2max
During endurance activity is being ATP resynthesized mainly aerobically from lipids and carbohydrates.
The more is O2 supplied to working muscles, the more higher is an amount of aerobically produced energy.
It means higher speed of running, latest manifestation of fatigue, etc.
It shows the capacity for aerobic energy transfer.

42. Decreases with age. Lower in female.
Average values of VO2max
Average (20/30 years) not trained:
- female 35 ml/kg/min
- male 45 ml/kg/min
Trained: to 85 ml/kg/min (cross-country skiing)
Decreases with age. Lower in female.

43. Average values of VO2max

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

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

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

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

48. 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…

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

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

51. 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

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

53. AnT (anaerobic threshold)
- exercise intensity, when anaerobic covering exceed aerobic.
- exercise intensity, when dynamic balance between production and breakdown of lactate is disturbed
level of lactate: 4 mmol/L of blood and is increasing (onset of blood lactate accumulation).
at about approximately 8 mmol/L o blood is impossible to continue in exercise (trained even 30 mmol/L of blood)

54. AnT (anaerobic threshold) - can be estimate from VO2max:
AnT = VO2max/3,5 + 60
AnT = 35/3,5 + 60
AnT = 70 %VO2max
1 MET
60 % of VO2max - AT

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

56. lactate
energy sources
fiber type
VO2max
[ml/kg/min]
onset of lactate accumulation – ↑ pH 45
fat < sugar
AnT
70-90 % VO2max
4 mmol/L
I., II. a, II. b
L is oxidized (heart ,not working muscles)
I., II. a
2 mmol/L
fat = sugar AT
50-60 % VO2max
fat > sugar I.
3,5
? 1,1 mmol/L
exercise intensity (speed, load, etc.)

57. (Hamar & Lipková, 2001)

58. Exercise intensity during endurance activity (>30 minutes) can not be above AnT.
Before start of exercise
- increase in O2 consumption (emotions, reflexions)
2) Initial phase of exercise (till 5 minutes)
- rapid increase in the oxygen consumption
Steady state
- balance between the energy required by working muscles and the rate of ATP produced by aerobic metabolism
- O2 is almost constant
- lactate level is constant
- HR is in the range ±4 beats (real steady state)

59. VO2max
[ml/kg/min]
O2 deficit
AnT
3.5
Time [min] 5 30
before start
initial phase
steady state

60. Oxygen deficit
Insufficient supply of working muscles with O2, at the beginning of exercise (slower ↑ SF and SV, BF and TV).
disbalance between O2 demands and supply leads to use of anaerobic metabolism – production of LACTATE ( ↑ H+ – metabolic acidosis – death point).
when O2 demands ensured – second breath
after termination of exercise the increased O2 consumption persists = oxygen debt

61. VO2max
[ml/kg/min]
O2 deficit
O2 debt
AnT
3.5
Time [min] 5 30
before start
initial phase
steady state

62. Oxygen debt synthesis of ATP and CP
resynthesis of lactate (back to glycogen in the liver, and oxidation by muscles and myocardium)
- acceleration of release of lactate from muscles and better blood perfusion of muscles resynthesising lactate, is possible by low intensive exercise: (till 50 % VO2max – below AT)
recovery of myoglobin, hemoglobin, hormone, etc.
the major part (till 30 min), mild oxygen debt can persist hours.

63. VO2max
[ml/kg/min]
false steady state
- above AnT
major O2 debt
AnT
3.5
Time [min] 5 25
before start
initial phase
steady state

64. VO2max
[ml/kg/min]
smaller O2 debt
AnT AP
3.5
Time [min] 2 30
before start
initial phase
steady state

65. oxygen consumption (L/min)
trained
- steady state is reached earlier
sedentary
- steady state is reached latter
rest
exercise
time (min)
(Hamar & Lipková, 2001)

66. Practical importance of VO2max
VO2max = 70ml/kg/min
AnP = VO2max/3,5 + 60
80%
VO2max = 35 ml/kg/min
70%
male A
female

67. Practical importance of VO2max
VO2max = 70ml/kg/min
VO2max = 70 ml/kg/min
90%
80%
male A
male B

68. Critical parameter of endurance abilities is not VO2max, but AnT.
However VO2max is conditional
parameter of AnT.