Lecture 4: Assessing Cardiorespiratory Fitness Flashcards
What are the main functions of the cardiovascular system (4)
1) The delivery of O2, fuel, & other nutrients to the
tissues of the body.
2) The removal of CO2 & waste products from the tissues.
3) The maintenance of a constant body temperature.
4) The prevention of infection.
What areht e componenets of the cardiovascular system?
Heart
blood vessels
blood
Define systole
the period of the heart’s contraction.
Define diastole
the period of the heart’s relaxation.
the blood flows into the heart.
What is the of role the heart
fist-sized muscle with 4 chambers located just beneath the ribs.
ROLE IS TO PUMP
1) O2-poor blood to the lungs,
2) O2-rich blood to the rest of the body.
What is the order of pulmonary circulation and then systemic circulation
oxygen poor blood > vena cava > right atrium > right ventricle > right ventricle contracts > pulmonary arteries
lungs >oxygenated blood > pulmonary veins > left atrium >left ventricle > aorta >body
What is the fucntion of pulmonary circulation? What is the fucntion of systemic circulation>
Pump O2 poor blood to the lungs
PUMP O2 rich blood to the rest of the body
HOw does the heart get blood supply?
The heart has its own network of arteries, veins, & capillaries.
the right & left coronary arteries, (branch off the aorta)
3 main functions of respitory system?
Supplies O2 to the blood.
Removes CO2 from the blood.
Regulates blood pH (acid-base balance).
(In exercise, blood is more acidic (more co2) and lungs must regulate it)
Where does the gas exchange happen? and how
alveolar capilaries
they have a ery thin layer between them and the red blood cells
explain the gas diffusion in the lungs (diagram)
Because of concentration gradient, there is a passive diffusion of oxygen to areas where pressure is lower
Explain BP and the relationship during systole and diastole
BP: The force exerted by the blood on the walls of the blood vessels
systole: BP increases
diastole: BP decreases
What is the formula for BP
BP = CO x TPR
where CO = cardiac output, &
TPR = total peripheral resistance.
explain total peripheral resistance
In a healthy person, TPR will not be high because blood goes through vessels, arteires open open, allowing blood into caperlleries, they feed oxygen and nurtrients to surrounding tissue)
What does systole provide an estimate of?
estimation of hearts work
what does diastole provide an estimate of ?
indirect indication of TPR or the ease with
which blood flows from the arterioles into the capillaries.
SHould BP increase during systole? during diastole?
BP increases during systole
BP SHOULD NOT INCREASE DURING EXERCISE
explain systole blood pressure during exercise
Increases linearly (10 +- 2mmHg per MET)
plateaus at peak exercise
max values 190-220
what is exertional hypertension and what should you do if you reach it>?
When systolic BP reaches about 250 mm Hg
When diastolic bP reaches greater than 115 mmHg
STOP TEST IMMEDIATELY
explain diastolic BP during exercise
may decrease slightly or remain unchanged.
due to a reduction in systemic vascular resistance in the muscles during exercise.
By increasing intensity, will cardio increase or decrease and why?
cardio output will increase because the bpdy needs more oxygen so SBP will increase
Define/explain max oxygen consumption (traditional/plateau)
a plateau in O2 consumption despite an increase in workload (attainment of VO2max during a maximum exercise tolerance test)
explain the plateau phenomenon and is it a prerequisity for determining trye VO2 max>
plateau in O2 consumption despite increase in work load
is not a prerequisite for true vo2 max
What is the MAIN/PRIMARY criteria used to indicate the attainment of VO2 max?
Oxygen uptake plateaus & does not increase by more than 150 mL· min-1 with a further increase in workload
What are the secondary criteria to determine the attainment of VO2 max.
If a VO2 plateau is not observed:
Failure of the HR to increase with increases in workload (exercise intensity).
A post-exercise venous lactate concentration > 8 mmol·L-1.
A respiratory exchange ratio (RER)(VCO2/VO2) ≥ 1.10.
At peak exercise, a RPE > 17 on the Borg 6-20 scale, or > 7 on the 0-10 scale.
What is the Verification Bout of Constant Load Exertion and is it suggested to be more appropriate for determining VO2 max?
refers to a bout of exercise that is about 10% higher than the highest workload achieved in a ramp trial. (supra max)
and yes by some people
When is a graded exercise measuring VO2 peak rather than VO2 max
if the test is terminated before the person reaches:
- a plateau in VO2 and
- a RER ≥ 1.10.
What is the definition of VO2 peak and when does it apply?
the highest rate of O2 consumption measured during a maximum exercise tolerance test regardless of whether or not a VO2 plateau was reached.
Applies when oxyggen consumption does not level off of when test performance is limited by msucular force and not cardiorespiroty ability
True or false: VO2 peak can be greater than VO2 max and is it a measure of index of VO2 max
True, it can be less or greater or equal and it is a valid index of mav VO2
What are the 4 groups of people who are more liekly tpo reach a VO2 peak instead of a manx?
Children
Older adults
Sedentary individuals
Clients with known disease
Define absolute and relative VO2 and some expressions of each
Absolute VO2
is the total volume of oxygen taken up (consumed) by the body.
(ex: L·min-1 , mL·min-1)
Relative VO2 is the volume of oxygen taken up (consumed) by the body relative to body weight. (mL·kg-1·min-1 mL·min-1·kg 0.67 or 0.75 mL·kgFFM-1·min-1)
What expression of VO2 max relative to FFM provide?
provides an estimate of CRE that is independent of changes in body weight
What does absolue VO2 measure
provides a measure of energy cost for non-weight bearing activities.
i.e., leg or arm cycle ergometry, rowing.
What does relative VO2 max measure
is used to estimate the energy cost of weight-bearing activities.
i.e., walking, running, aerobic dancing, stair climbing, bench stepping.
true or false: relative VO2 will not underestimate the VO2max of obese individuals.
false, it may understimate
What are the 2 factors that affect relative VO2 max>
improved cardiorespiratory system capacity (increased absolute VO2max) and/or weight loss (fat loss).
what are the 2 expressions of O2 consumptoon
gross vo2 net vo2 (exercise vo2)
Explain gross VO2
is the total rate of O2 consumption.
reflects the caloric costs of both rest & exercise
= Resting VO2 + Exercise VO2.
explain net VO2
represents the rate of O2 consumption in excess of the resting VO2.
is the Exercise VO2.
is used to describe the caloric cost of the exercise.
= Gross VO2 − Resting VO2. (3.5)
how can oxygen consumption (max) be measured and estimated
measured: open circuit spirometry
estimted: max treadmill time, power output, heart response
is open circuit spirometry a direct or indirect measure of VO2 max>
DIRECT TEST
explain open circuit spirometry
In this procedure, the subject breathes through a low-resistance valve with the nose occluded while pulmonary ventilation & expired fractions of O2 & CO2 are measured.
Using chemical gas analyzers to determine the O2 & CO2 content.
What are the factors that affect VO2 max?
mode of exercise; treadmill>bike>rowing
heredity: heart size, lung capacity, RBC content
age: between 25-75 VO2 decreases by 1% every yr
sex: males> fms
physical training: increases by 6-20%
body comp
What the procedures for adminestering a GXT
1) measure resting BP and HR in exercise posture
2) 2-3 warm up (explain and prepare)
3) monitor HR and BP and RPE at reg intervals (HR at least last 2 min, BP and RPE at the end of the stae)
4) know when to discontinue the test
5) end with active cool down
6) take BP and HR for at least 5 minutes
7) potentially use passive cool down
When should you take HR during a GXT and what needs tp be reached at the end of each stage>
HR: at least 2 times during each stage, near the end of the 2nd & 3rd minutes of a 3-minute stage.
A steady-state HR should be reached for each stage of the test.
(do not increase worload until SSHR)
WHen should you take BP and RPE and when should the BP be repeated ?
BP & RPE: near the end of the last minute of each exercise stage.
BP should be repeated if a hypotensive or hypertensive response is observed.
What is the purpose of an active cool down?
Reduces the risk of hypotension
What are the reasons for discontinuing a test?
reaches the test termination criteria (i.e., 70% HRR, 85% APMHR),
fails to conform to the exercise test protocol,
experiences adverse signs or symptoms (i.e., any of the indications for stopping a GXT),
requests to stop the test, or
experiences an emergency situation.
When would you use a passive cool down in a sitting or supine position?
Use a passive cool-down in a sitting or supine position if:
your client has signs of discomfort, or if
an emergency occurs.
When is the normal reasons to stop atest
reaching a measured VO2max,
volitional fatigue, or
a predetermined end point
(70% HRR or 85% MHR)
When does a max GXT normally stop>? submax?
max: client voluntarily stops
submax: predetermined end 70% HRR or 85% MHR
What are the general indications for stopping a test
-Onset of angina or angina-like symptoms
-Drop in SBP of greater than 10 mm with an increase in work rate or if SBP decreases below the value obtained in the same position prior to testing
Excessive rise in BP
SBP > 250 mm Hg or DBP > 115 mm Hg
Shortness of breath, wheezing, leg cramps, or intermittent claudication
Signs of poor perfusion (light-headedness, confusion, ataxia, pallor, cyanosis, nausea, or cold & clammy skin)
Failure of HR to increase with increased exercise intensity
Noticeable change in heart rhythm by palpation or auscultation
Individual requests to stop
Physical or verbal manifestations of severe fatigue
Failure of the testing equipment
What does it mean when there is an irregular beat?
Irregular beat: SIGNAL DIDN’T STARTT FROM THE RIGHT NODE (started in a hot spot)
normally starts from sinoatrial node
What are the absolute indications for stopped a test
signs of poor perfusion axaxia, near symcope, dizzy ANGINA increase DBP or decrease in SBP asks to stop sustained ventricular tacchtcardia
what are the relative indications
increasing chest pain
fatigue, shortnes sof breath, cramps
arytthmias other than tachycadia
SPD greater than 250 aor DBP greater than 115
What do you based the selection off a graded exercis test on
age, gender, pintial fitness, health
purpose
cost/time
valididate, reliability, objectivity
What are the advanteages of a maximal GXT
used to diagnose CAD or other disease
prognosis
refine exrecise prescripTION
what are the disadvantages of a maximal test
must go to volatile fatugue
need a phycian potentially
might need emergency equipment
what are the advantages of a SUBMAXIMAL gxt
used to predict vo2 max
less money
multistage and shorter duration
what are the diaadcnatges of a submaximal test
prediictions/not actual
not precise
limited diagnostic utility
what is steady state
2 consecutive HR measirements that are within 5 bpm of each other
true or false: there is no linear relationship between HR and work rate
false, there is a positive relationship between them
what are the factors that could increase HR
tobacco, caffeine, temp, stress, food digerstion, altitude
what are some of the assumptions we make for a graded exercuse test?
A steady-state heart rate (HRSS) is achieved for each exercise work rate (WR).
A linear relationship exists between HR & WR.
110 to 150 bpm.
The difference between actual and predicted maximal HR is minimal.
Mechanical efficiency (i.e., VO2 at a given WR) is the same for everyone.
The individual is not on any medications that may alter the heart rate response to exercise.
The individual is not using high quantities of caffeine, ill, or in a high-temperature environment, all of which may alter the HR response.
*The most accurate estimate of VO2max is achieved if all of the preceding assumptions
are met. Error is ~ ± 10% - 20%.
what factors could decrease HR
if taken supine or in the morning
