see to understand

1. Effect of Exercise on Cardiovascular
System
Prof.Dr: Amr Abo-Gazia

2. • Students, Learning Objectives:
• Ÿ
Know the basic structure and function of the CVS.
• Ÿ
List Functions of the CVS during exercise.
• Ÿ
Explain the responses and adaptation of CVS to
exercises

3. • Components of the Cardiovascular (CVS)
System: The CVS includes the heart and the
vascular system
• THE HEART :
• The heart is a muscle that is required to
contract continuously throughout the life to
deliver oxygen to all organs in the body and
breathe out carbon dioxide

4. • Components of the heart
• Four chambers 2 atria
• 2 ventricles (left thicker than right)
• Major veins Superior vena cava
• Inferior vena cava
• Pulmonary veins

5. • Major arteries
• Aorta Pulmonary trunk
• Valves permit the passage of blood in one
direction.
• Tricuspid
• Atrioventricular
• Bicuspid
• mitral
• Semilunar
• Aortic
• Pulmonary

7. • VASCULAR SYSTEM (BLOOD VESSELS )
• Transports blood throughout the body, to and
from the heart, via systemic circulation.
• Transports blood to and from pulmonary
circulation.
• Different names for vessels:
• Arteries (arterioles) – Carries blood away from
heart.
• Capillaries – gas exchange between tissue and
blood.
• Veins (Venules) – Carries blood toward the heart.

8. • The path of blood from the body to the heart and back out to the body
• Deoxygenated blood comes from the body to the inferior and superior vena
cava.
• Blood enters right atrium, pressure increases and tricuspid valve opens.
• Deoxygenated blood enters right ventricle pressure increases and
pulmonary valve opens
• Deoxygenated blood goes to the lungs via pulmonary artery where diffusion
occurs in the capillary beds- CO2 and O2 exchange occurs.
• Oxygenated blood returns via pulmonary veins.
• Blood enters left atrium pressure increases and bicuspid valve opens.
• Blood flows into left ventricle pressure increases aortic valve opens.
• Oxygenated blood flows to the body via aortic arch.

9. • Circulation of Blood:
• Pulmonary Circulation: deoxygenated blood is
pumped from the right side of the heart
through the pulmonary arteries to the lungs.
Oxygenated blood is returned by the
pulmonary veins.

10. Pulmonary Circulation

11. Systemic Circulation: oxygen rich blood is pumped from the left
side of the heart through the aorta to the rest of the body.

12. • Functions of The Cardiovascular System during
exercise
• The cardiovascular system serves five important
functions during exercise:
• 1. Delivers oxygen to working muscles
• 2. Deoxygenates blood by returning it to the lungs
3- Transports heat from the center to the skin
• 4. Delivers nutrients and fuel to active tissues
• 5. Transports hormones

13. • Response and Adaptation of the CVS to Exercise:
• 1-Heart rate
• 2-Stroke volume
• 3-Cardiac output
• 4-Blood flow
• 5-Blood pressure
• 6-Blood

14. • HEART RATE
• Resting heart rate (HR) averages 60 to 80
beats/min in healthy adults.
• Short term response :– HR increase by the
release of noradrenaline (sympathetic) causes
increase in the force of contraction of the
heart à increased stroke volume à increased
ejection fraction.

15. • Long term adaptation :- Heart rate decreases due to decrease in
sympathetic tone. In elite endurance athletes heart rates as low as 28 to
40 beats/min.
• Anticipatory response (increased heart rate before exercise) Caused by
the release of epinephrine
• Before exercise even begins heart rate increases in anticipation
(expectation).
• This is known as the anticipatory response.
• It is mediated through the releases of neurotransmitters epinephrine and
norepinephrine also known as adrenaline and noradrenaline (adrenal
gland).

16. • Stroke volume (SV)
• Is the amount of blood ejected per beat from left ventricle and
measured in ml/beat.
• Stroke volume increases proportionally with exercise intensity.
• In untrained individuals stroke volume at rest it averages 50 - 70
ml/beat
• during intense, physical activity stroke volume increasing up to
110 - 130 ml/beat
• In elite athletes resting stroke volume averages 90 - 110 ml/beat
increasing to as much as 150 - 220ml/beat .

17. • Cardiovascular Drift: an increase in heart rate
during steady exercise due to a reduction in stroke
volume. Caused by:
• Exercising in heat
• Rise in core temp.
• Decrease in plasma volume.

18. • Ejection fraction: The percentage of blood ejected out
of the ventricles during each contraction.
– At rest, the ejection fraction is only about 50%.
– During exercise, it can increase to 100%.
– The ejection fraction at rest is low due to Q (Cardiac output)
sufficiently supplying all the cell with oxygen.
• As the demand for oxygen increases during exercise,
the ejection fraction increases to supply the demand of
oxygen

19. • Cardiac Output
• Cardiac output (Q) is the amount of blood pumped by
the heart in 1 minute
• measured in L/min. It is a product of; stroke volume
and heart rate (SV x HR).
• Resting Q:
• Q = HR x S
• = 70bpm x 70mL = 4.9 L/min

20. Cardiac Output Heart Rate Stroke Volume
Untrained 5000 70 71
Trained 5000 50 100

21. • Exercise Q
• Cardiac output provides most significant indicator of circulatory system›s
functional capacity to meet demands for exercise.
•
• From rest to steady-rate exercise, Q increases rapidly, followed by gradual
increase until its plateau’s.
• If either heart rate or stroke volume increase, or both, cardiac output
increases also.
• Since Q=HR x SV, cardiac output increases from 4.2 L/min to 25 L/min.
• Cardiac Output remains relatively unchanged or decreases only slightly
following endurance training.
• During maximal exercise on the other hand, cardiac output increases
• significantly. This is a result of an increase in maximal stoke volume

22. • Ejection fraction
• The percentage of blood ejected out of the
ventricles during each contraction.
• At rest, the ejection fraction is only about 50%. During
exercise, it can increase to 100%.
• The ejection fraction at rest is low due to Q sufficiently
supplying all the cells with oxygen.
• As the demand for oxygen increases during exercise, the
ejection fraction increases to supply the demand of oxygen.
•

23. • Blood flow
• The vascular system can redistribute blood to those tissues with
the greatest immediate demand for energy such as muscles
(Skeletal muscle receives a greater blood supply)
• Blood flow from heart increases in direct proportion to exercise intensity
• At rest 15 - 20% of circulating blood supplies skeletal muscle.
• During vigorous exercise this increases to 80 - 85% of cardiac output.
• The body will redirect blood away from the viscera (intestine, pancreas, etc.)
and to the working muscles for oxygen delivery, supplying the demand.
• Body core temperature will also increase, resulting in further
vasoconstriction and sphlanchic circulation, increasing blood flow
to the skin for loss of heat via radiation

24. Distribution of Blood at rest and during
exercise
Distribution of Blood Liver kidneys muscle Brain Heart Skin
Rest
Q = 5000 ml
1350 ml 1100 ml 1000 ml 700 ml 200 ml 300 ml
Exercise
Q = 25000 ml
500 ml 250 ml 21000 ml 900 ml 1000 ml 600 ml

25. • Blood Pressure
• At rest
• Atypical systolic blood pressure in a healthy individual ranges
from 110 - 140mmHg and 60 - 90 mmHg for diastolic blood
pressure.
• Blood Pressure Acute Response to Exercise:
– Bloodpressurewillincreaseduetothecardiacoutputincreasingsubsta
ntially.
– During exercise systolic pressure, the pressure during contraction
of the heart (known as systole) can increase to over 200mmHg
and in highly

26. • trained, healthy athletes.
Dynamic Exercise: systolic pressure increases with intensity with
relatively little change in diastolic pressure. Ex. Walking, jogging,
swimming and cycling.
– Static Exercise: heavy resistance training increases blood pressure
both systolic and diastolic pressure due to muscular contractions
compressing
• peripheral arteries. Ex. Isometric resisted exercise, isometrics.
– Dynamic muscular exercise which works specially with arms causes a
great increase in the blood pressure above the normal values. Such
type of
• exercise should be avoided with cardiac patients.

27. • Chronic adaptation of blood pressure to
exercise
• Regular endurance training decreases systolic
and diastolic pressure.

28. Blood
• Blood: transport vehicle for nutrients,
hormones, waste products and electrolytes.
• From exercise point of view, the
transportation, temperature regulation and
the acid base balance is of prime importance
functions of the blood.

29. • 55% of total blood volume is plasma, 45% is blood cells and
platelets
• Blood cells include:
– Erythrocytes: (RBC’s) Contain hemoglobin that binds to oxygen
for transport to tissues.
– Leukocytes: (WBC’s) defend the body against disease.
– Platelets: (thrombocytes) play a role in the clotting of blood.
• Plasma: 90% water and 10% solutes
– Metabolites and wastes (gases, hormones, vitamins)
– Salts (ions)
– Plasma proteins

30. • Oxygen Transport in the Blood:
• Hemoglobin: (Hb) iron containing pigment that
binds with oxygen to form oxyhemoglobin. Hb + 4
O2 = Hb4O8

31. • Oxygen carrying capacity of the blood
• Energy production through Kerbs cycle or
mitochondrial respiration depend on continuous
supply of oxygen.
• Enhanced oxygen delivery and utilization during
exercise will improve mitochondrial respiration
and subsequently the capacity for endurance
exercise.

32. . Exercise places an increased demand on the
cardiovascular system to pump more oxygen to supply the
working muscle to produce energy (aerobic oxidation).
. Oxygen demand by the muscles increases, more
nutrients are needed and more waste is created.
. A reduction in the oxygen carrying capacity in conditions
such as anaemia produces fatigue and shortness of breath
so affect performance.

33. • A trained subject with greater volume of blood is
able to meet the circulatory demands of the active
muscles than untrained subjects.
• Increase in the plasma volume following
endurance training increases blood volume, which
in turn increase stroke volume and cardiac output
with increased availability of oxygen to the active
tissue so increasing VO2 max.

34. • On the contrary, when a trained subject stops training
(detraining occurs), there is a reduction in the
plasma volume which would decrease the VO2max.
During strenuous exercise in a hot climate, the
sweating rate is from 1 to less than 2 liters per hour.
• This increased sweating may reduce the total blood
volume (haemoconcentration) by 3% or more.

35. • Electrolytes
• Electrolytes are important because they are what your
cells (especially nerve, heart, muscle) use to maintain
voltages across their cell membranes and to carry
electrical impulses (nerve impulses, muscle
contractions) across themselves and to other cells.
• The kidneys work to keep the electrolyte
concentrations in your blood constant despite changes
in the body.

36. • When performing exercise heavily or exercise at hot
weather, we lose electrolytes in the sweat, particularly
sodium and potassium.
• These electrolytes must be replaced to keep the
electrolyte concentrations of your body fluids constant.
• So, avoid exercising at hot weather and also many
sports are encouraged to drink drinks have sodium
chloride or potassium chloride added to them.

37. • Summary of Cardiovascular Adaptations to
Exercise:
• Lower resting heart rate.
• Increased left ventricular volume.
• Increased stroke vol. and cardiac output.
• Capillarization: increase in capillary surface area in
muscles.
• Greater arteri-ovenous oxygen diff. (a - vO2)

38. • Benefits of Cardio. Fitness
– Improved fat metabolism
– Efficient delivery of oxygen
– Faster removal of wastes
– Decreased levels of stress

39. Physiological Response and Adaptations to
Exercise
Responses Adaptations
HEART
» Heart rate increases.
» Cardiac output increases.
» SV increases from resting level.
» Coronary circulation increases.
Max HR may be achieved.
» Resting HR decreases.
» SV increases during rest & work.
» Blood supply to heart muscle increases during rest &
work.
» Volume of left ventricle increases after aerobic training.
» Hypertrophy of the left ventricle after anaerobic
training.
» Max HR remains the same.
» HR at sub-max workloads falls.
» Cardiac output at max workloads increases.

40. CIRCULATORYSYSTEM
» Systolicbloodpressureincreases.
» Speedofbloodflowincreases.
» Bodytemperatureincreases.
» Arterio-venousO2diffincreases.
» Vasodilationoccurs.
» Redistributionofbloodflow.
» Maintainedelasticityofarterywalls.
» Diminishedfattydeposits.
»Lowriskofhighbloodpressureandcardiovascular
disease.
» Capillarysupplytoheartandskeletalmusclesincreases.
» Bloodvolumeincreases.
» Hemoglobincountincreases.
» Oxygen-carryingcapacityofbloodincreases.

41. • Monitoring Exercise Intensity
• Resting Heart Rate (RHR)
• Lowest HR, least amount blood required.
• Between 60 - 100bpm.
• Target Heart Rate (THR): HR your are trying to reach for a specific
goal.
• Maximum Heart Rate (MHR): maximum heart rate that you can
attain. Based on your genetics, should not train at this rate.
• MHR =220-age
• Purpose: used to create target training zones to help improve your
cardiovascular capacity and progress the intensity of your workouts

42. • Heart Rate Training Zones: are calculated by
taking into consideration your max. heart rate
and your resting heart rate.

43. • Training Zones
– Warm up zone 50 - 60% of MHR
– Fitness zone (fat burning) 60 - 70% of MHR
– Aerobic zone 70 - 80 % of MHR
– Anaerobic zone 80 - 90% of MHR

45. •Thank You