fat

Question 1

what is energy equivalent of oxygen

Answer 1

20 kj/L

Question 2

ATP yield from anaerobic glycolysis

Answer 2

4 atp in total net gain of 2 atp, 3 from glycogen

Question 3

ATP from aerobic metabolism

Answer 3

34 atp from aerobic metabolism so net gain of 36 or 37 atp

Question 4

ATP yield glucose vs fat

Answer 4

depends on chain length of fatty acid
palmitate is 16 chain fatty acid
beta oxidation generates acetyl coA which generates 1 NADH (3ATP) and 1 FADH (2ATP)
7 cycles gain of 5 so 35ATP in goal
TCA cycles generates 3NADH and 1 FADH so we get 11 ATP x 8 cycles 96 ATP
Total of 131 ATP from fat

Question 5

why might we want to enhance fat oxidation during exercise

Answer 5

save glycogen stores, limited store
more energy from oxidising fat, more atp
greater fat stores than carb stores
enhance exercise capacity/performance during endurance sport

Question 6

where does peak oxidation of fat occur

Answer 6

65%VO2Max

Question 7

What are Fat oxidation rates

Answer 7

typically between 0.5-0.6g per minute

Question 8

which fibres are fat stored in

Answer 8

type 1 muscle fibres stores more fat
decrease in fat stores following exercise in type 1 but type 2 remains stable in terms of fat stores

Question 9

Limitations to fat oxidation

Answer 9

complex to oxidise fats
breakdown triglyceride to release free fatty acids, they aren’t water soluble so has to be carried in the blood by a carrier protein albumin, takes it to the muscle cell, where fatty acids can be oxidised or be stored as intramuscular triglyceride
they have to be transported across multiple cell membranes to be able to be oxidise or stored

Question 10

what is albumin

Answer 10

protein in the blood responsible for carrying free fatty acids

Question 11

effect of endurance training on fat oxidation

Answer 11

greater fat oxidation at the same absolute exercise intensity

Question 12

what adaptations occur that allow us to become better fat burners

Answer 12

increased maximal oxygen uptake
increased mitochondria (oxidative enzymes)
increased capillaries (enhanced oxygen delivery and extraction)
increased fatty acids transporters

Question 13

how does training increase intramuscular triglyceride utilisation

Answer 13

increase in oxidation from non plasma fa, increase utilisation of intramuscular triglyceride stores

Question 14

how does pre exercise carbohydrate intake influence ffa availability and fat oxidation

Answer 14

reduces and limits oxidation

Question 15

what does lipid heparin do

Answer 15

increase ffa availability

Question 16

what does heparin activate

Answer 16

lipoprotein lipase

Question 17

what does lipoprotein lipase do

Answer 17

breaks down triglycerides into ffa

Question 18

how does intralipid infusion effect glycogen breakdown

Answer 18

reduce glycogen breakdown
studies show by 40%, sparing glycogen

Question 19

how does a short term high fat diet effect performance

Answer 19

impair performance due to reduce carb availability
not long enough to allow favourable adaptations to occur

Question 20

what follow up work has been done ok high fat diets

Answer 20

long periods of training with increased fat intake/reduced carb intake
re fed carbs to replenish glycogen stores (fat adaptations, carb restoration model)

Question 21

downside of a high fat adapted diet

Answer 21

decrease pdh activity, decreased maximal oxidative glucose performance
decrease power output, unable to maintain power output
reduced utilisation of glycogen, impairs high intensity

Question 22

training with increased fat intake/reduce carb intake leads to what adaptations

Answer 22

increased fat oxidation
increase fatty acids transporters and enzymes if beta oxidation
reduced pdh activity