Energy expenditure

Question 1

RER

Answer 1

ratio between co2 produced and o2 consumption

Question 2

1 MET

Answer 2

energy required to cover resting metabolic rate

Question 3

1 MET =

Answer 3

3.5ml/kg/min

Question 4

EPOC

Answer 4

occurs to refuel cells

Question 5

calorie

Answer 5

amount of energy to raise 1g of water by 1 degree

Question 6

why measure energy expenditure

Answer 6

assess metabolic needs
fuel utilisation
thermic effects of food
assess economy

Question 7

direct calorimetry

Answer 7

measure heat given off during exercise

Question 8

pros of direct calorimetry

Answer 8

direct measure of heat
accurate for steady state measures

Question 9

cons of direct calorimetry

Answer 9

expensive
slow to generate results
few in operation

Question 10

RER for 1 molecule of glucose

Answer 10

1.0

Question 11

RER for 1 molecule of palmitic acid

Answer 11

0.70

Question 12

what does indirect calorimetry predict

Answer 12

substrate usage

Question 12

benefits of indirect calorimetry

Answer 12

can detect changes with breath by breath system
easy to administer
fairly accurate for aerobic
direct assessment of gas exchange

Question 13

Which fuel substrate costs the most oxygen per kilocalorie

Answer 13

fats

Question 14

assumptions of indirect calorimetry

Answer 14

body o2 is constant
co2 exchange in lungs is proportion to release from cells
little contribution from protein

Question 15

limitations of indirect calorimetry

Answer 15

values >1 won’t provide valid estimation
inaccurate approaching 1
gluconeogenesis from fat and AA <0.7
not appropriate outside range of 0.70-1

Question 16

BMR over time

Answer 16

2-3% decrease over 10 years
decrease fat free mass
depression of metabolic activity of lean tissue
altered by change in body composition and physical activity

Question 17

MET

Answer 17

multiples of RMR

Question 18

VO2

Answer 18

200ml/min for average woman
250 men

Question 19

2 met activity is

Answer 19

7ml/kg/min

Question 20

Fat max

Answer 20

exercise intensity at which max fat oxidation is observed

Question 21

why does fat max occurs

Answer 21

lower availability of plasma FFA
reduced entry of fatty acids into mitochondria

Question 22

level of runners and VO2 max

Answer 22

slower recreational = 60-65% RER 0.9 CHO 68%
faster = 70-75% RER 0.95 CHO 84%
elite = 80-90% RER 2.02-2.10

Question 23

mechanical efficiency

Answer 23

external work accomplished / energy expenditure

Question 24

EPOC

Answer 24

delay in post exercise oxygen consumption

Question 25

EPOC fast component

Answer 25

rapid decline in oxygen uptake during first 2-3mins after

Question 26

EPOC slow component

Answer 26

after 2mins and persists for up to an hour

Question 27

EPOC extra slow component

Answer 27

several hours before basal level returns

Question 28

reasons for EPOC fast component

Answer 28

resynthesis of ATP and PCr o2 levels restored to myoglobin and haemoglobin thermogenic effects of hormones

Question 29

reasons for slow EPOC component

Answer 29

re synthesis lactate to glycogen thermogenic effects of elevated core temp HR and VE remain elevated for several mins after