Lab Exam 1

Question 1

define energy

Answer 1

the capacity to do work

Question 2

what is the independent variable in a graded exercise test

Answer 2

work rate

Question 3

what is the independent variable in a constant work rate exercise?

Answer 3

time

Question 4

examples of absolute measurements

Answer 4

0.25 L/min or 1000 W

Question 5

examples of relative measurements

Answer 5

3.5 mL/kg/min or 12 W/kg

Question 6

how is relative aerobic power expressed

Answer 6

%VO2 max

Question 7

rate of heat production is proportional to what?

Answer 7

metabolic rate

Question 8

when is indirect calorimetry valid?

Answer 8

only when energy comes from oxidative pathways

Question 9

VO2 is proportional to what?

Answer 9

energy expenditure during aerobic tasks

Question 10

equation for gross efficiency

Answer 10

mechanical power / metabolic power

Question 11

why is gross efficiency never 100%?

Answer 11

human machine is not efficient because some energy is lost as heat

Question 12

what factors influence gross efficiency

Answer 12

work rate, cadence, fiber type, contraction type

Question 13

what is the dynamic energy balance equation

Answer 13

rate of change of energy stores = rate of change of energy intake - rate of change of energy expenditure

Question 14

factors that affect basal metabolic rate

Answer 14

fat-free mass, age, sex, body fatness, genetics, caloric restriction/starvation, exercise

Question 15

what is resting basal metabolic rate

Answer 15

3.5 mL/ kg*min = 1 MET

Question 16

what factors determine fuel selection?

Answer 16

1) intensity
2) duration
3) training status = increase oxidative capacity
4) diet - CHO supplementation (timing is important)

Question 17

how does training status affect fuel selection?

Answer 17

“crossover” point shifts RIGHT (happens at a greater VO2 max) so you increase fat utilization, increased mitochondrial and capillary density, increased FFA transport and oxidation, and glycogen sparing

Question 18

how does consuming CHO before or during exercise affect fuel selection?

Answer 18

increases CHO utilization and decreases fat utilization

Question 19

how does consuming a high CHO diet in general or a high fat diet in general affect fuel selection?

Answer 19

increases CHO utilization during submaximal exercise, whereas consuming a high fat diet increases fat utilization

Question 20

what is the Fick equation

Answer 20

VO2 = Q x (a-v)O2 difference

Question 21

how do we use the Fick equation to determine VO2 max?

Answer 21

VO2 max = maximal cardiac output x (maximal a-v O2 difference)

Question 22

how does an increase in max stroke volume affect VO2 max?

Answer 22

increases VO2 max

Question 23

how does an increase in (a-v) O2 difference max affect VO2 max?

Answer 23

increases VO2 max

Question 24

how does an increase in max HR affect VO2 max?

Answer 24

because an increase in heart rate is accompanied by less filling time and therefore decreased stroke volume, VO2 max does not really change

Question 25

why is VO2 max lower in women?

Answer 25

women have a decreased cardiac output, decreased hemoglobin, and decreased muscle mass compared to men

Question 26

what kind of training increases VO2 max?

Answer 26

moderate to high intensity training

Question 27

why does the percent change in VO2 max with training differ among individuals?

Answer 27

dependent on individual’s pre-training fitness level

Question 28

what are “anaerobic” energy sources? what is the better term?

Answer 28

ATP/PC and non-oxidative glycolysis; better termed “immediate” energy stores

Question 29

what enzyme performs this reaction: ATP + H2O —> ADP + Pi

Answer 29

ATPase

Question 30

what enzyme performs this reaction: CP + ADP —> ATP + C

Answer 30

creatine kinase

Question 31

what enzyme performs this reaction: ADP + ADP —> ATP + AMP

Answer 31

adenylate kinase

Question 32

potential factors that may limit anaerobic performance

Answer 32

1) energy depletion (Pcr) 2) metabolite accumulation (H+ ions, inorganic phosphate) 3) central and peripheral fatigue

Question 33

how does training improve anaerobic performance?

Answer 33

increasing type 2 skeletal muscle fibers, improving the ATP-PCr system, and improving glycolysis system

Question 34

does aerobic training improve anaerobic performance?

Answer 34

yes, because all 3 energy systems are active

Question 35

T/F: increase in cardiac output with endurance training is due to the ability to get higher max heart rates

Answer 35

FALSE

Question 36

what 2 conditions does O2 consumption represent total energy expenditure?

Answer 36

submaximal, steady state

Question 37

T/F: the wingate test can accurately and reliably measure anaerobic energy production

Answer 37

false

Question 38

T/F: all constant work rate exercise is at steady state

Answer 38

false

Question 39

if an individual were trying to lose weight, would it be more advantageous to have a higher or lower gross efficiency?

Answer 39

gross efficiency = mechanic power/ metabolic power to burn more calories, we want to increase metabolic power, because metabolic power is inversely proportional to gross efficiency, gross efficiency would be lower

Question 40

what is the dominant energy system at 5 seconds of anaerobic exercise?

Answer 40

immediate (ATP-PC)

Question 41

what is the dominant energy system at 20 seconds of anaerobic exercise?

Answer 41

nonoxidative glycolytic

Question 42

by what mechanism might skeletal muscle hypertrophy increase the maximal power generated by a muscle?

Answer 42

by increasing surface area of muscle, you can increase the maximal amount of cross bridge formation

Question 43

how might the effects of skeletal muscle hypertrophy on power be limited if metabolic enzymes didn’t also increase?

Answer 43

even if we have more muscle mass, if we don’t have an accompanying increase in metabolic enzymes, we cannot increase energy production via either glycolytic systems or the ATP-PC system

Question 44

how does an increase in cardiovascular and muscular fitness due to aerobic training affect an individual’s performance on the Wingate test?

Answer 44

this would improve an individuals Wingate performance because they could use more oxidative energy sources and spare immediate energy stores for peak power output

Question 45

when is it true that you burn more total calories of fat at a lower intensity compared to a higher intensity?

Answer 45

when the change in total energy expenditure is small in comparison to the decrease in % relative contribution of fats

Question 46

when is it true that you burn less calories from fat at a lower intensity as compared to a higher intensity?

Answer 46

when the change in total energy expenditure is large in comparison to the decrease in relative % contribution from fats

Question 47

how much air do you lose when analyzing gas using PARVO?

Answer 47

.35 L / min