Lab 5: Maximal Exercise Testing

Question 1

VO2 max testing

Answer 1

-Measures oxygen consumption
-Volume of O2 utilized by bodily tissues in order to produce energy per unit of time

Question 2

VO2 max testing unit

Answer 2

Volume of O2 (L)/Unit of time (Min)

Question 3

Maximal O2 consumption depends on

Answer 3

1. Cells ability to extract and use aerobic metabolism O2 for large amounts of ATP and muscle mitochondria for ATP synthesis
2. Ability of cardiovascular & respiratory systems to transport O2
   -Cardiovascular: Cardiac output
   -Respiratory component: Ventilation

Question 4

Practical rationale for VO2 testing

Answer 4

-Guiding recommendations for return to work after cardiac events
-Developing exercise prescriptions in those with known heart diseases
-Gold standard to objectively measure exercise capacity

Question 5

Absolute VO2

Answer 5

-L/min
-Total amount of oxygen consumed

Question 6

Relative VO2

Answer 6

-mL/Kg/min
-Total amount of oxygen consumed per kg of body weight

Question 7

Respiratory Exchange Ratio

Answer 7

-(VCO2 produced/VO2 consumed)
-Estimates composition of fuels being used for energy
-RER ranges from 0.7-1.0

Question 8

Metabolic equivalent of tasks

Answer 8

-METs=(Relative VO2/3.5)
-Estimate the amount of energy used during physical activity
-Can be used to compare exertion required for different activities (2 MET uses 2x the calories per minute than rest)

Question 9

Determining VO2 max (Criteria)

Answer 9

At least 2 of criteria must be met:
-Respiratory exchange ration >1.1
-Rating of perceived exertion >17
-Venous lactate concentration > 8 mmol/L
-Plateau of VO2 less than 0.15 L/min
HR within 10 beats of age predicted HR max

Question 10

What if less than 2 criteria is met

Answer 10

VO2 peak is achieved
-Highest VO2 achieved in a maximal exercise test without plateau
-Usually occurs because subject quits before achieving a true maximal exercise capacity.

Question 11

Factors affecting VO2 max

Answer 11

-Sex
-Age
-Training status
-Body composition
-Altitude

Question 12

Difference in VO2 max in males and females

Answer 12

Males tend to have 15-20% higher VO2 max than females

Question 13

Age impact on VO2 max

Answer 13

VO2 max will decrease by 1% yearly after 25%\

Question 14

Training status impact on VO2 max

Answer 14

Elite distance runners can have VO2 maxes over 30 mL/kg/min across both sexes higher since they have more lean mass

Question 15

Impact of altitude on VO2 max

Answer 15

Higher altitude has less O2 per given amount of air

Question 16

Termination criteria for a GXT

Answer 16

-Onset of angina
-Significant drop in SBP or failure of SBP to rise with intensity
-Signs of poor transfusion
-Subject requests to stop
-Failure of HR to increase with increased intensity
-Noticeable change in HR
-Physical or verbal manifestations of severe fatigue
-Equipment failure