Lab 4: Aerobic Fitness

Question 1

what does the VO2 max test measure?

Answer 1

the maximal capacity to transport and utilize oxygen during dynamic exercise involving a large muscle mass

Question 2

how is VO2 max measured?

Answer 2

via indirect calorimetry during a maximal graded exercise test

Question 3

how does oxygen consumption change in relation to work rate?

Answer 3

oxygen consumption increases linearly with work rate until VO2 max is reached

Question 4

once VO2 max is reached, does an increase in work rate increase oxygen consumption?

Answer 4

no

Question 5

what does VO2 max represent?

Answer 5

the physiological limit of the body to deliver and extract oxygen

Question 6

how can VO2 max be visualized on a graph?

Answer 6

when there is a plateau in oxygen consumption with an increase in work rate

Question 7

what 2 physiological factors is VO2 max dependent on?

Answer 7

1) the maximal ability of the cardiovascular system to deliver oxygenated blood to working tissues
2) the maximal ability of the working muscles to extract oxygen and produce ATP aerobically

Question 8

how does the Fick equation determine VO2 max?

Answer 8

determines VO2 max as a product of cardiac output and oxygen extraction (arteriovenous oxygen difference)

Question 9

how do training adaptations increase VO2 max?

Answer 9

by increasing either cardiac output or arteriovenous oxygen difference

Question 10

increased cardiac output volume seen following endurance training is due to..

Answer 10

increase in maximal stroke volume

Question 11

how is stroke volume increased following endurance training?

Answer 11

increase in end-diastolic volume (or preload) and cardiac contractility & decrease in afterload on the ventricles

Question 12

does maximal heart rate increase with endurance training?

Answer 12

no

Question 13

how might arteriovenous oxygen difference increase?

Answer 13

increased capillary density and mitochondrial density, as well as biochemical and metabolic adaptations

Question 14

what is the specificity principle?

Answer 14

VO2 max test should ideally involve the specific movements used by the athlete in their event (trained cyclist uses a cycle ergometer)

Question 15

why do treadmill tests generally produce greater VO2 max values?

Answer 15

involves more muscle masses (upper body)

Question 16

what is the most important criteria in determining one’s VO2 max?

Answer 16

a plateau in oxygen consumption after an increase in work rate

Question 17

at least 2 of the following criteria must be met to determine VO2 max, what are the criteria?

Answer 17

1) plateau in rate of oxygen consumption (VO2) following an increase in workload
2) RER > 1.15
3) HR > age predicted maximal HR -10
4) rate of perceived exertion (RPE) > 17
5) blood lactate > 8 mM

Question 18

what is the rate of perceived exertion (RPE) scale? how is it used?

Answer 18

the RPE scale is a valid indicator of exercise intensity and it was developed to predict the HR of a 20 y.o. at a given work rate by multiplying the RPE by ten (HR is approx. 60 bpm at RPE of 6)

Question 19

4 primary factors the affect an individual’s oxygen consumption

Answer 19

1) genetics
2) sex
3) training status
4) age

Question 20

how does VO2 max for females compare to that for males?

Answer 20

VO2 max for females tends to be lower because of differences in cardiac output, hemoglobin, and muscle mass

Question 21

what kind of training produces the greatest increase in VO2 max?

Answer 21

moderate to high intensities rather than low intensity training

Question 22

how does VO2 max change with age? why?

Answer 22

VO2 max decreases with age due to reductions in maximal cardiac output and maximal O2 difference

Question 23

how does maximal HR change with age?

Answer 23

decreases linearly with age

Question 24

how does endurance training affect the decline in HR with aging?

Answer 24

it doesn’t

Question 25

how does muscle mass change with age?

Answer 25

decreases

Question 26

what is lactate threshold

Answer 26

the point at which blood levels of lactate begin to rise exponentially

Question 27

how might lactate threshold be measured if we can’t measure blood lactate?

Answer 27

via the ventilatory threshold; the point at which there is a sudden increase in ventilation, which is an estimate of the lactate threshold

Question 28

where do the lactate/ ventilatory thresholds occur in untrained individuals?

Answer 28

50-60% VO2 max

Question 29

where does the lactate/ ventilatory threshold occur in trained athletes?

Answer 29

65-85% VO2 max

Question 30

what is exercise/running economy?

Answer 30

the oxygen cost of exercise at a given speed (running) or power output (cycling)

Question 31

what factors influence movement economy

Answer 31

body mass, terrain, footwear, stride length

Question 32

when comparing individuals running at the same submaximal speed, the individual with the greatest movement economy…

Answer 32

consumes the least oxygen, it “costs” less O2 to run at that speed

Question 33

what is an athlete’s 10,000 m race pace correlated to?

Answer 33

their speed at lactate threshold

Question 34

describe the procedure

Answer 34

students in 3 groups (only one group exercising at a time); exercising student chooses either the treadmill or bike, subject gets a warmup phase

treadmill: start at 3.5 mph then increase until 70% of student’s max HR is reached, then stop the treadmill and set up equipment, each stage of test is 2 mins long, the incline is raised 2% each time until max incline of 10% reached

bike: warmup at a workload that elicits HR of < 130 bpm, start test at predetermined kp and 80 rpm (subjects must stay at 80 rpm), each stage is 1 min long and the kp is increased by pre determined amount until volitional fatigue