Week 11: Pre Lab Quiz Ch 19: Determination of Maximum Oxygen Uptake

What is maximum oxygen uptake (VO₂max )`

VO₂max is the maximum amount of oxygen the body can take in, transport, and use during maximal exercise

How is VO₂max measured?

A test where a person exercises at increasing intensity until exhaustion (usually on a treadmill or bike), while oxygen use is measured.

When are the best results of the VO₂max test obtained?

When the tests lasts between 9-15 minutes before the subjects is reaches exhaustion

VO₂max can be tested using any exercise that meets what requirements?

• Use big muscles (like legs)

• Make your heart and lungs work hard for a continous period of time to get a result

How is VO₂max expressed (mathematically)

Theres 2 ways:

1. Absolute (gross)

   • Litres per minute (L/min) = total oxygen your body uses

2. Relative

   • mL/kg/min = oxygen use based on your body weight (adjusted for body weight)

What are the ways that VO₂max measurements are used for?

1. Identify Fitness level (who has high endurance vs low)

2. To see if training works (did endurance improve?)

3. Understand work/conditions (ergonomics) (how hard tasks are on the body/effects of heat altitude)

4. detect health problems (ex. heart lungs or muscle diseases)

What the the requirements to do the VO₂max

1. Work needs to involve large muscle groups (ex. running cycling)

2. Exercise is continous with gradually increasing intensities

3. Resistance should be selected so that the subject will be exhausted in 7 to 10 minutes after the warm up

4. not steady state= getting harder continously so your body cant catch up

5. Test conditions must be comparable and repeatable

6. work rate must be measureable and reproducible

How do you know if someone has reached their VO₂max

1. Oxygen consumption stops increasing even though intesnsity increases ( last 2 values agreeing within + 125 mL (1.5-2.0 mL/kg))

2. High blood lactate at 8.0 mM/liter or greater, 3-5 minutes after stopping exercise

3. Heart rate should be close to the age predicted maximum (220 - age)

4. Respiratory exchange ratio (RER = Co2 out/ O2 in) greater than 1.15

5. subjective fatigue, exhaustion, and an inability to continue

What are the 2 types of methods to measure VO₂max

1. Manual (old school)

   • Air breathed out was collected in a big ballon during exercise, afterwards they check how much oxygen and CO2 is inside and they also measure how much air you breathed out.

2. Automated (modern)

   • Air breathed in goes through a pneumotachograph or turbine device

   • air breathed out goes into a mixing box (mixes all you breath together)

   • small samples are drawn continously and routed to the gas analyzer (measures O2 and CO2)

   • Everything goes to a computer (calculates Vo2 instantly)

whats a pneumotachograph

a specialized medical device used to measure the rate of airflow during breathing (respiration)

• measures how fast air is moving

whats a Analog voltage signal

machine converts breathing into electrical signals

whats the Data acquisition system

system that collects and records data

whats the Microcomputer

the computer doing calculations

whats Breath-by-breath analysis

measures every single breath in real time

Name all the equipement needed to perform the VO2 max test.

1. weighing scale

2. electrically braked bicycle ergometer

3. heart rate monitor

4. stopwatch

5. low resistance respiratory valve plus mouthpiece

6. noseclip

7. collins non-kinkable hose

8. electronic carbon dioxide analyzer

9. electronic oxygen analyzer

10. calibration gases for gas analyzers

11. mercury barometer

12. mouthpiece sterilizing soution

13. metrological balloons

14. ventilation meter

15. 2 way valve

term for the piece of equipment used for the work/ exercise being done, where resistance is controlled electronically

Electrically braked bike ergometer

What’s a low resistance respiratory valve plus mouthpiece

you breath through this

whats the collins non kinkable hose

tube that doesn’t bend/block airflow

what are the Calibration gases

known gas values used to make sure machines are accurate

whats the Mercury barometer

measures air pressure (affects gas calculations)

whats the Meteorological balloons

collects breath

whats the Ventilation meter

measures air volume

what does the 2 way valve do

controls direction of airflow (in vs out)

What should the avoid avoid before excerise

1. extermes of climates and exercise for 24 hours before the test

2. the subject should be well rested

3. Drugs, alchol, cigarette smoking and large meals should be avoided at least 2-4 hours before

How are you gonna prepare the subject and equipment in order?

1. subject fill out concent form

2. calibrate oxygen and carbon dioxide analyzer using a gas of known composition

3. obtain subjects body mass

4. record barometric pressure

5. place the heart rate meter on the subject

6. Check heart rate during the last 5 seconds of each minute during the warm up, and exercise test procedure

7. Fit respiratory valve and mouthpiece to the subject using a lightweight headgear, rubber valve flaps in the respiratory valve should be checked to ensure that they move freely and do not leak.

8. Make sure subjec't’s expired air is flowing in the proper direction through the respiratory valve.

9. put the nose clip on the subject’s nose

10. have tissues and waste basket available for the end of test as subject usally want to remove mouthpiece right away, catch saliva in tissues and hang the hose/mouthpiece apparatus so that it drains into the wastebasket

11. rinse the mouth piece and respiratory valve throughly with warm tap water, then place them in the disinfectant solution

A test performed with no rest between the exercise increments is known as __ while a test where there are several minutes of recovery between exercise increment are known as __

1. Continous exercise test

2. Discontinous test

Is this test a continous exercise test or a discontinous test

continous exercise test because there are no rests between exercise increments

What should the pedaling frequency be at?

should be 80 rpm or higher

What is the purpose of the warm up period

1. to get the heart lungs and muscles ready to work (to warm the body up)

2. to help the subject get used to the bike, breathing set up and how it feels (get comfortable with the test)

3. helps the experimenters practice their particular measurement task

True or false the subject will proceed directly from the warm up period into the exhaustive exercise protocol without taking a rest break

True

What are the reasons to stop exercise?

1. subject is unable/unwilling to proceed for any reason

2. signs the body is struggling (physiological problems)

   • complaints of increasing angina (chest pain, caused by heart not getting enough oxygen)

   • severe dyspnea (severe trouble breathing)

   • severe fatigue (extreme exhaustion and cannot continue safely

   • feeling faintness

   • nausea

   • claudication (severe leg pain/ cramping due to poor blood flow)

3. Signs of possible emergency

   • pale skin (losing normal colour)

   • cold moist skin

   • cyanosis (blue lips or nail beds)

   • mental confusion

   • shakiness

What is angina

chest pains causes by heart not getting enough oxygen

What is dyspnea

severse trouble breathing

What is claudication

serve pains or craming in legs caused by poor blood flow

What is cyanosis

blueish lips or nail beds from not getting enough oxygen

True or false when in doubt stop the test

True

What does the recovery process look like

• the subject keeps cycling slowly to cool down until they feel okay again

• DO NOT LEAVE THEM ALONE

  • They are at a higher risk right after exercise of passing out, because when they exercising the heart is pumping lots but the muscles are moving blood back to the heart called the skeletal muscle pump , but during recovery the hearts pumping alot the blood vessels are wide and dilated but the muscles arent moving so less blood returns to the heart so blood can pool in the legs, less blood to brain and dizziness or fainting wi=ould occur

Expired Gas Collection and Analysis

1. The respiratory valve controls the directional flow of the subject’s inspired and expired air. When the subject expires, the inspiratory valve is closed and the expiratory valve opens. All of the subject’s expired air is channeled through the Collins non-kinkable hose, through the two-way tap, and then either into a meterological balloon or out to the room air, depending on whether or not a gas sample is being collected for that particular minute.

2. Collect expired gas in meteorological balloons for the second minute at each work rate until the subject gets close to exhaustion, and then collect gas every minute. When a balloon has been collected, lay it down on the floor out of the way. The gases in the balloons will be analyzed after the exercise test is completed.

3. Analyze the gas composition of each balloon by drawing a gas sample from the balloon through the O2 and CO2 analyzers. Allow the gas analyzers to sample from each balloon until the readings stabilize.

4. Determine the minute ventilation (V.EATPS) by squeezing the contents of the balloon through the ventilation meter. Record the temperature of the gas as
   it goes through the ventilation meter.

5. Record data in Table 19-2

what are the responsibilities of the students during perforamcne of this test

• 1 as subject

• 1 adjusts work rate on bicycle

• 1 student will call out the time

• 3 students will monitor the heart rate using heart rate meters

• 2 studetns will collect gas bags

• 1 student will stand next to the subject and be prepbared to make any adjustments to monitoring equipment that is attached to the subject

Whats Boyles law

if the temperature remains constant theres no inverse relationship between pressure and volume

Whats charles law

If pressure is held constant there is a direct relationship between the absolute temperature and volume

what is STPD stand for and why do we need to

STPD stands for Standard Temperature and Pressure, Dry. used to ensure gas measurements are accurate

Order of calculations

• Correct expired air to STPD

• Find oxygen in expired air

• Find oxygen in inspired air

• Subtract → VO₂

Does nitrogen change in body and how is it used

Its unchanged in the body and used to calculate inspired volume

Bike vs treatmill vo2max

Treadmill has a higher VO2max because running uses more muscle groups, thus more oxygen is needed

What does VE ATPS represent

air breathed out (raw)

What does VE STPD represent

air breathed out (corrected)

What does FEO2 represetn

ocygen in expired air

What does FIO2 represent

oxygen in inspired air

what does VO2 represent

oxygen used