What Adaptations Occur With Cardiovascular Training?

Question 1

Heart rate:

Answer 1

no. of heart beats/min

Question 2

End diastolic volume

Answer 2

volume of blood in left ventricle just prior to

contraction

Question 3

End systolic volume

Answer 3

volume of blood in left ventricle following contraction

Question 4

Stroke volume:

Answer 4

volume of blood ejected from the left ventricle with each heart beat (difference between EDV-ESV)

Question 5

cardiac output

Answer 5

total volume of blood ejected from the heart per minute (equal to HR x SV)

Question 6

a-v O2difference

artery - venus

Answer 6

difference in partial pressure of oxygen between the blood in the arterial and venous systems. Reflects amount of O2extracted from blood

Question 7

CV SYSTEM OVERVIEW

Answer 7

The CV system supplies O2 for metabolism, eliminates CO2 producedduringmetabolism, and regulates H+ concentration to maintain acid-base balance
The exchange of O2 and CO2 occurs in the alveoli of the lungs the blood gas interface.

Question 8

CV SYSTEM OVERVIEW - Heart

Answer 8

delivers oxygen and nutrients to the muscles and removes waste products by pumping blood through the CV system

Question 9

CV SYSTEM OVERVIEW - Lungs

Answer 9

oxygenate the blood and remove CO2

Question 10

CV SYSTEM OVERVIEW - vessels

Answer 10

delivers blood to tissues and from tissues

Question 11

How is O2 transported in the blood?

Answer 11

98.5% bound to hemoglobin in red blood cells (remaining 1.5% dissolved in plasma)

Question 12

How is CO2 transported in the blood?

Answer 12

1. Dissolved in plasma (7%)
2. Carbamino compounds (23%) – bound to Hb inside red
   blood cells
3. Bicarbonate ions (HCO3-) (70%) – in RBC CO2 reacts
   with water to form carbonic acid which dissolves into H+ and bicarbonate (HCO3-)

Question 13

NORMAL RESTING VALUES - HR

Answer 13

60-100 beats per minute. This value can decrease with improved fitness and increase with age.

Question 14

NORMAL RESTING VALUES - BP

Answer 14

BP can vary with changes in posture, exercise, stress or sleep, it should normally be 120/80 mm Hg for an adult age 20 or over. >140/ 90 mmHg is considered mild hypertension and >180/110 mmHg is considered a hypertensive crisis. <90/60 mmHg is considered hypotensive.

Question 15

NORMAL RESTING VALUES - Respiratory rate:

Answer 15

12 -20 breaths per minute (12 breaths per minute is considered normal for an adult)

Question 16

EXERCISE IS ABOUT TO START

Changes in respiration occur even before the initiation of exercise

Answer 16

Increased gas exchange across the alveolar-capillary membrane by the first or second breath.
– Increased respiratory rate

Question 17

EXERCISE IS ABOUT TO START

Exercise Pressor / Anticipatory Response:

Answer 17

Increased SNS activity, release of norepinephrine and epinephrine
– includes generalized peripheral vasoconstriction in non-exercising muscles and viscera, an increased myocardial contractility, an increased heart rate, and an increased systolic blood pressure.

Question 18

DURING EXERCISE

Answer 18

CARDIOVASCULAR AND RESPIRATORY SYSTEMS MUST MEET THE RAPID INCREASE IN ENERGY REQUIREMENTS DURING EXERCISE
Increased cardiac output Increased minute ventilation Increase in heart rate

Question 19

DURING EXERCISE - CHANGE IN CO2

Answer 19

There is a marked increase and redistribution of the cardiac output.
This occurs due to a combination of the anticipatory response and a locally mediated reduction in resistance in the working muscle arterial vascular bed, independent of the autonomic nervous system, and is produced by metabolites such as Mg2+, Ca2+, adenosine diphosphate (ADP), increased PCO2, decreased PO2, increased lactic acid, and increased temperature.

Question 20

DURING EXERCISE - MINUTE VENTILATION

Answer 20

Minute ventilation (the volume of air in inspired or expired per minute ) increases
MV increases as respiratory frequency and tidal volume increase. Alveolar ventilation, occurring with the diffusion of gases across the
capillary-alveolar membrane, increases 10-20x during heavy exercise to supply the additional O2 needed and excrete the excessive CO2 produced.

Question 21

• What causes the observed increase in MV?

Answer 21

– Acombinationofneuralandchemicalfactors,anyofwhich
alone or in combination may stimulate the respiratory system:
• Increased muscle metabolism results in more O2 extraction from arterial blood (increased a-VO2 difference) resulting in an increase in venous PCO2 and H+, an increase in body temp, increased epinephrine, and increased stimulation of receptors of the joints and muscles
– ThingsotherthanexercisecaninfluenceMV-Baroreceptor reflexes, protective reflexes, pain, emotion, and voluntary control of respiration may also contribute to the increase in respiration

Question 22

HR DURING EXERCISE

Answer 22

This depends on the intensity. If exercise intensity continues to increase HR will also continue to increase in a linear fashion until the maximum HR (HRmax) is achieved.
• If intensity is maintained at a submaximal level, HR increases rapidly until a plateau is reached. This is referred to as the
steady-state HR. This is the optimal HR for meeting the circulatory demands at a specific rate of work.

Question 23

EXERCISE RESULTS IN ADAPTATIONS

Answer 23

The cardiovascular system and the muscles adapt to a training stimulus over time
Adaptations result in improved efficiency of the cardiovascular system and the active muscles at rest and during exercise
Adaptation is relative to baseline fitness – an individual with low level of fitness has more potential to improve.

Question 24

ADAPTATIONS - CARDIOVASCULAR CHANGES

Answer 24

Cardiac adaptations:
Hypertrophy of cardiac muscle, increased left ventricular internal dimension, end diastolic volume, increased stroke volume (Frank- Starling Mechanism), increased myocardial mass, decreased HR at a given workload, rapid return to resting HR
Peripheral adaptations:
capillary density, increased red blood cells and total blood volume, increased a – vO2 difference at submaximal and maximal loads

Question 25

ADAPTATIONS - BLOOD FLOW AND PRESSURE

Answer 25

• Increased ability to supply blood to muscles (blood flow) – Increasedcapillarisation
– Increasedabilitytodilate
• Decrease in resting blood pressure in hypertensive individuals

Question 26

ADAPTATIONS - BLOOD VOLUME

Answer 26

Increased blood plasma volume
– Releaseofaldosteroneandantidiuretichormonewithexercise – Increasedplasmaproteins
• Increased number of red blood cells – Decreasedbloodviscosity
– Higherturnoverofcells

Question 27

ADAPTATIONS - RESPIRATORY CHANGES

Answer 27

• Ventilatory efficiency is increased
• Minimal changes in lung volumes
• Small decrease in resting and sub-maximal respiratory rate
• Improvements during exercise
– Maximal minute ventilation
– Oxygendiffusioncapacityincreasesduetoincreased capillarisation

Question 28

ADAPTATIONS - METABOLIC CHANGES

Answer 28

• Increased size and number of skeletal muscle mitochondria – increasing capacity to generate energy aerobically
• Increased myoglobulin – increasing rate of transport of oxygen transport
• Decreased rate of depletion of muscle glycogen
• Lower blood lactate levels at submaximal work

Question 29

VO2 MAX

Answer 29

The integrated result of these adaptations is to increase the maximum amount of oxygen used by the body during dynamic exercise.
This is referred to as the VO2max (in L/min or ml/kg/min)

Question 30

VO2 MAX DEF

Answer 30

the maximal CO (represents the oxygen delivery and blood flow to metabolically active tissue) and the maximal a-v O2 difference (the ability of metabolically active tissue to extract and use O2 from the blood)
VO2max = COmax x a-v O2 Diffmax

Question 31

AT 12 DAYS

Answer 31

DECREASE IN VO2 MAX, CARDIAC OUTPUT STROKE VOL
INCREASE IN A-V O2 DIF MAX. , HR PEAKS
2ND DECREASE BY 21 DAYS

Question 32

tidal vol.

Answer 32

The amount of air which enters the lungs during normal inhalation at rest.
norm = 500ml