week 9 lab v02 max Flashcards
what does the Vo2 max measure
the power of the oxygen transport system
what is generally used for the v02 test
cycle ergometer
best results are obtained from tests that are how many minutes?
9-15
how is the measurement of VO2 max determined? what is the general procedure
measurement of the subjects exhastive response from max work where work rate is increased in incremental steps
4 uses for v02 max measurements
- to indicate individuals with high endurance abilities
- to evaluate the effects of training on endurance
- measure the metabolic costs of various work tasks under normal or non normal conditions
- detect impaired cardiorespiratory function or metabolic diseases
What are the 6 Methodolical Criteria for administering a maximum oxygen uptake test
- work should involve large muscle groups
- continuous work with gradual increasing intensities
- work intensity must be selected so subject will be exhausted in 7-10 min after warmup
- work rate should be heavily so oxygen uptake is not entirely correspond with energy requirement of work load
- the work rate must be measurable and reproducible
- test conditions must allow results to be comparable and repeatable
what is the Criteria for REACHING v02 max (5)
- oxygen consumption hits a plateau and last 2 values agree with +-125ml
- blood lactate levels 8.0mM/liter after 3-5 minutes since stoping exercise
- heart rate should be close to age predicted max
- respiratory exchange ratio must be greater than 1.15
- subject must be exhuasted
what is the manual system for measuring oxygen uptake V02 max
- exhaled gas collected in balloons
- after co2 and o2 levels in ballons is determined by analyzing a small sample
content of ballons is squeezed through a ventilation meter
what is the automated measuring system of max oxygen uptake
- gas directed through a pneumotachograph or turbine device that measures air flow rate
- sends an analog voltage signal to computer system
- mixing box analyses samples of gas
- computer takes info and calculates the oxygen upatake during excersise
automated measuring methods considerble improved the ______________ compared to manual tests
time expenditure for tests
what should subject do before test
- provide any excersise they did
- well rested and no drugs, cigarettes or alcohol 2-4hrs before test
steps to prep subject
- calibrate machines
- get body mass
- barometric pressure
- heart rate meter on subject before warm up and measure heart rate in last 5 seconds of each min
- ensure respirtory value and mouthpiece are fit and no leaks and proper direction of exhaled air
- nose clip
- tissues
whats type of excersise test is this and why
a continuous excersise test where there is no rest between increments
what should the pedaling frequency be
80rpm or higher
what is the warm up period
the first 6 minutes
stop the excerise when
- subject is unable or doesn’t want to continue
- evidence of phsyiological problems
- signs of impeding emergency situation (pale skil, blue lips, shakiness)
how should subject recover
cool down on bike until they feel recovered, do not leave subject alone
how is the expired gas analyzed
- expired air chanelled through hose,
- gas collected in baloons for the second minute at each work rate until exhaustion
- analyze co2 and 02 in balloons
- determine minute ventilation
how do we determine the minute ventilation
by squeezing contents of the balloon through the ventilation meter
what is boyle’s law
if the temperature remains constant there is an inverse relationship between pressure and volume of VO2 upatke
what is charles law
is pressure is held constant there is a direct relationship between the temperature and volume
what are all volumes corrected to
STPD - standard temperature, pressure dry (no water vapour)
amount of oxygen consumed =
the amount of oxygen inhaled minus the amount of oxygen exhaled
what is assumed about nitrogen gas in inhalation/exhale
the volume of nitrogen inhaled equals the volume exhaled
a change in nitrogen is due to
change in the volume of the gas mixture
the volume of gas is dependent on
the number of molecules present, not the size of the molecules
what does atmospheric air consist of
n2, o2 and co2
when using the bicycle ergometer u have to multiply the subjects VO2 by
1.07
what is Ve atp
minute ventilation of expired air
what is Tgas
tempature in degrees celcius of gas passing through ventilation meter