Aerobic Power

Question 1

What are the most important factors that determine VO2 max in a person? (5)

Answer 1

1) ability to ventilate the lungs and oxygenate the blood passing through the lungs
2) ability of heart to pump blood - cardiac output
3) 02 carrying capacity of blood
4) ability of working muscles to accept large blood supply
5) ability of muscle fibres to extract o2 from capillary blood and use it to produce energy

Question 2

What are the VO2 max test protocols? 3

Answer 2

1) exceed 6 mins but be less then 15 mins
2) first stage of test - warm up period
3) protocols should be arranged in stages, each stage progressively increasing in intensity until termination criteria is reached

Question 3

What is the criteria for attainment of V02 max? 5

Answer 3

1) 02 consumption ceases to increase linearly w increasing work rate and approaches plateau, last two values +2 ml/kg/min
2) HR close to age predicted maximum (220-age)
3) blood lactate levels = 8mm/L or greater, 3-5 mins post exercise
4) respiratory exchange ratio greater than 1.10
5) subjective observations - did subject look exhausted at end of test?

Question 4

FACTORS AFFECTING MAX AEROBIC POWER

how should athletes be tested in mode of exercise?

Answer 4

mode of exercise of their sport

Question 5

how can you determine highest V02 max in most subjects

Answer 5

uphill treadmill running

Question 6

what are the two main types of bicycle ergometers?

Answer 6

1) mechanical: monarch ergometeres

2) electrically braked bicycle ergometer: resistance provided by moving conductor through a magnetic field

Question 7

why are the advantages of bicycle ergometers as compared to treadmills for exercise testing? 5

Answer 7

1) less expensive
2) portable
3) dont require electricity
4) patient stable, body weight supported = easier to collect physiological data during exercise
5) easier to quantify work rate

Question 8

disadvantages of bicycle ergometers? 2

Answer 8

1) cannot obtain as high of v02 max as treadmill

2) cycling not common movement, walking is more

Question 9

how is heredity a factor affecting max aerobic power?

Answer 9

vo2 max max is 40 - 50% genetically determined

Question 10

how is age and sex a factor affecting max aerobic power?

Answer 10

vo2 max increases with age, peak is 18-25 yrs old

vo2 max declines 1 % a year

Question 11

what are the reasons for decrease of vo2 max after 25?

Answer 11

1) decrease in max HR and negative changes in oxygen transport system
2) older, less active

Question 12

sedentary vs active people

Answer 12

nearly two fold faster rate of decline in vo2 max

Question 13

what is diff between boys and girls of v02 max after puberty?

Answer 13

male has 20-25 % higher than avg female

Question 14

what are reasons for the sex diff?

Answer 14

1) males has move muscle less fat - muscle metabolically more active tissue
2) avg male 10-14 higher hemoglobin concentration

Question 15

What are some tests used to predict VO2 max?

Answer 15

predictive test

heart rate exercises

Question 16

why use predictive test?

Answer 16

1) less $$, special equipment needed
2) tests can be submaximal - safety
3) some tests for large groups
4) less motivation is required from subject

Question 17

what are predictions based on heart rate based on?

Answer 17

1) linear relation b/t HR and oxygen uptake
2) similar max HR for all subjects
3) work rate: fixed mechanical efficiency is assumed
4) day to day variation in heart rate

Question 18

what is efficiency of muscular work?

Answer 18

% of chemical energy converted to mechanical nrgy w the remainder lost as heat

Question 19

what is the calculation of mechanical efficiency?

Answer 19

%EFF= (work performed kcal/ energy expended kcal) x 100

Question 20

what is efficiency of large muscle - activities walking, running cycling?

Answer 20

20-25 percent