lab 2: exercise lab

Question 1

what is oxygen uptake?

Answer 1

a measure of a person’s ability to take in oxygen and deliver it to the working tissues, and the ability of working tissues to use oxygen.

oxygen is essential for muscle energy production during exercise- the body increases its oxygen intake by increasing ventilation (rate and tidal volume)

Question 2

minute ventilation (VE)

Answer 2

the total volume of air breather per minute and is calculated by multiplying breathing rate by tidal volume
*both increase during exercise

Question 3

tidal volume

Answer 3

amount of air that moves in or out of the lungs with each respiratory cycle

Question 4

VO2 max

Answer 4

measures how much oxygen your body consumes while exercising

VO2 is a measure of how much oxygen the body utilises per minute. VO2 max is the highest amount of oxygen the body can consume and is often used to assess aerobic fitness.

Question 5

douglas bag method

Answer 5

this method is used in the lab; air is collected in a large neoprene bag while the participant breathes out.

after collecting expires gas, the sample is analysed for oxygen and carbon dioxide content; helps calculate minute ventilation V02 and CO2 production

*more modern method is metabolic carts which measures every breath

Question 6

calculation process of VO2

Answer 6

expires gas sample is corrected for standard temperature and pressure for dry air to account for environmental changes

oxygen uptake (VO2) is calculated by knowing the volume of air inspired, the fraction of oxygen inspired, and the fraction of oxygen in the expired gas

Question 7

resting VO2

Answer 7

a typical resting oxygen uptake for a healthy individual is around 0.2 to 0.5 litres per minute. It’s important to assess whether a participants resting VO2 falls within this range, and if not, understand why it might be higher or lower.

Question 8

typical value of VO2 max

Answer 8

VO2 max values in healthy individuals typically range between 3-5 litres per minute;
elite athletes possibly reach up to 7.3 litres per minute;
sedentary individuals usually fall in the in the range of 2-3 litres/minute.

*VO2 can also be expressed in relative terms (ml/kg/min), which accounts for body mass

Question 9

respiratory exchange ratio (RER)

Answer 9

RER is the ratio of CO2 production (VCO2) to oxygen uptake (VO2), and it helps determine which substrate (fat/carb) is being utilised for energy.
an RER of 1.0 or above indicates carb metabolism while RER of 0.7 or below indicates fat metabolism

Question 10

what RER value indicates fat metabolism?

Answer 10

0.7 or below

Question 11

what RER value indicates carb metabolism?

Answer 11

1.0 or above

Question 12

exercise intensity and VO2 relationship

Answer 12

as exercise intensity increases, VO2 typically increases in a linear fashion.
the relationship between work rate (exercise intensity) and VO2 is a good marker of how well the body is performing.
heart rate also correlates with exercise intensity, and fit individuals generally show a lower heart rate for the sae intensity due to a higher stroke volume (amount of blood ejected per heart beat)

Question 13

heart rate relationship in more fit people

Answer 13

heart rate correlates with exercise intensity, and fir individuals generally show a lower heart rate for the same intensity, due to a higher stroke volume (amount of blood ejected per heart beat)

Question 14

lactate threshold

Answer 14

point at which lactate accumulates in the blood due to higher exercise intensity.
regular high-intensity interval training can improve this threshold, allowing an athlete to perform at higher intensities before lactate accumulates.