NUS - VO2 Practical

8/3/2019 NUS - VO2 Practical

http://slidepdf.com/reader/full/nus-vo2-practical 1/24

METABOLIC EXERCISE TESTING

CONCEPTS, PROCEDURES & APPLICATIONS

Lee Kai Wei Jason, PhD

Senior Member of Technical Staff

Military Physiology Laboratory

DMERI, DSO National Laboratories.

Tel: 6485 7106Email: [email protected]



Reasons for metabolic exercise testing

Basic components of VO2max testing

Commonly Adopted Criteria for VO2max





2max

the highest rate of oxygen consumption attainableduring maximal or exhaustive exercise 1

1Wilmore JH & Costill DL. (2005) Physiology of Sport and Exercise: 3rd Ed. Champaign,

IL: Human Kinetics



2max

Indicator of aerobic potential , not a predictor of successin endurance events

Largely hereditary, training has little effect on VO2 max



2max

Indicator of aerobic potential , not a predictor of successin endurance events

Largely hereditary, training has little effect on VO2 max



To evaluate:

Sub and maximal work capacity.

Effectiveness of training programmes.

Effectiveness or impact of intervention

Basis for exercise prescription

Diagnosis of cardiopulmonary

abnormalities.



For evaluation of training programme

y = 4.938x - 19.496

R2 = 0.9979

35

40

45

50

55

60

65

11 12 13 14 15 16 17

Speed [km/h]

V

O

2

[ m

l / m

i n / k

]

y = 11.14x + 7.0133

R2 = 0.9927

135

140

145

150

155

160

165

170

175

11 12 13 14 15 16

Speed [km/h]

H e a r t R a t e

[ b p m

]

3 months

later

3 months

later



VO2: L. Min-1 VS ml.kg-1.min-1

Subject A

BW = 60kgVO2= 3 L.Min-1

VO2 in ml.kg-1.min-1

= 3000

60= 50 ml.kg-1.min-1

Subject B

BW = 70 kgVO2 = 3 L.Min-1

VO2 in ml.kg-1.min-1

= 3000

70= 43 ml.kg-1.min-1



2max



YesNoNoOxygen used?

Stored

carbohydrate,

fat and protein

Muscle glycogen

and blood glucose

Adenosine

triphosphate

(ATP)

Fuel

SlowRapidImmediateRate of ATP

production

Low to

moderateHighHigh

Intensity of

activity

More than 2

min11-120s0-10 s

Duration of

activity

OxidativeGlycolyticATP-PCCharacteristics

Adapted from Walters and Byl (2008)



So which sites

are limiting?



Determining VO2 measurement by the Fick equation:

VO2 = Cardiac Output x A-V O2 Difference

Stroke Volume x Heart Rate Peripheral O2 ExtractionX



Determining VO2 measurement by

respiratory equation:

VO2 = ( FIO2 x VI) (FEO2 x VE)

Inspired O2 content

(20.93% at sea level)

Inspired

Volume

(Measured)

Expired O2

(Measured)Expired

air volume

(Measured)



Inspired Air

20.93% O2

0.03% CO2

79.04% N2X

Inspired Vol

Expired Air

FEO2

FECO2

FEN2

X

Expired Vol

± =

VO2

VCO2

VE

+B.Wt

VO2 l min-1

VO2 ml kg-1 min-1

VCO2

l Min-1

RERVE /VO2

Kcal

Regular calibration

necessary. Measured Derived



Mode of testing should be appropriate to theindividual being tested.

For athletes, should be sport specific.

Incremental stages.

Continuous vs. Discontinuous.

2max



2max



A plateau is defined

as an increase in

oxygen consumption

of less than 2 ml·kg-

1·min-1 or 3% with

an increase in

exercise intensity.

OXYGEN CONSUMPTION (VO2max)





Heart rate increases in direct proportion to increases in

exercise intensity until close to the point of exhaustion.

HEART RATE (HR)

Heart rate within ± 10

beats·min-1 of the age-predicted maximum

HRmax = 220 - age in years.





Blood lactate concentration rises with increasing

exercise intensity. A post-exercise blood lactateconcentration of 8 mmol·l-1 can be used as a

criterion for the achievement of VO2max

BLOOD LACTATE CONCENTRATION

RATING OF PERCEIVED EXERTION

A rating of perceived exertion (RPE) of 19 or 20

on the Borg 6 to 20 rating of perceived exertion

scale can be used as a criteria for the attainmentof VO2max



1) A plateau in oxygen consumption.

2) A RER value of 1.15 or above.

3) A heart rate within ± 10 beats·min-1

of age predicted maximum.

4) A VE/VO2 value > 30.

5) A post-exercise blood lactate

concentration of 8 mmol·l-1 or above.

6) A RPE of 19 or 20 on the Borg scale.

Commonly Adopted Criteria for VO2max



Documents

NUS - VO2 Practical