Lecture 2 - Lipids Part 2

Question 1

what lipids are transported directly into the blood

Answer 1

• glycerol
• short chain fatty acids
• medium chain fatty acids

Question 2

what lipids are transported through lymph system, then blood

Answer 2

triglycerides

cholesterol

phospholipids

Question 3

what is the theory about high fat diets and trained peoples fat useage

Answer 3

trained people will use more fat than an untrained person at a given time

Question 4

what are some metabolic adaptations to exercise the lead to increased use of fat as a fuel

Answer 4

• increased capillarisation of muscle
• increased intramuscular triglycerides
• increased in number and size of skeletal muscle mitochondria

Question 5

metabolic adaptations to endurance exercise allow a trained individual to use proportionally ….

Answer 5

more fat and less CHO at a given workload

Question 6

is it possible to combine high fat diets with endurance training and cumulatively enhance …..

Answer 6

fat metabolism and physical endurance

Question 7

increasing the proportion of fat used in exercise will decrease the rate of …. utilisation and spare….

Answer 7

decrease rate of CHO utilisation and spare muscle glycogen

Question 8

fat as a fuel can not be used ….

Answer 8

can not be used anaerobically

Question 9

what is the short term adaptation to high fat diets (3) (1-3 days)

Answer 9

• decreased resting muscle and liver glycogen stores
• decreased CHO oxidation during subsequent exercise
• impairment of endurance capacity and performance of prolonged exercise

Question 10

what are the short term adaptations to high fat diets due to a combination of (1-3 days)

Answer 10

• decrease muscle glycogen stores
• absence of any worthwhile increase in fat utilisation capacity
• reductions in wellbeing

Question 11

what is the short term adaptation to high fat diets (3) (5-10 days)

Answer 11

high fat diets > metabolic adaptations > increased fat oxidation during exercise

compensate for decreased CHO availability

Question 12

studies have shown what about training capacity when been 3 weeks ketogenic, but what is this very variable between

Answer 12

studies have shown that training capacity can be restored within 2-3 weeks, but very variable between athletes

Question 13

many studies show that performance on the ketogenic diet is …. or

Answer 13

not different or worse off

Question 14

what are the long term endurance performance adaptations to a high fat diet (non ketogenic) - what do studies show

Answer 14

majority of studies show no difference in endurance performance when comparing adaptation to high fat and high CHO diets

Question 15

what are the factors to consider when designing diets for endurance athletes

Answer 15

• individual preference
• total energy expenditure
• time for recovery
• nature of the sporting event

Question 16

what years did CHO popularity grow due to muscle biopsy technique

Answer 16

CHO popularity grew with work using muscle biopsy technique = 1960s

Question 17

when were very low CHO diets (ketogenic diets) were developed for weight loss. Are individuals able to perform endurance exercise on these very low CHO diets?

Answer 17

1970s

Question 18

factors affecting fat oxidation during exercise

Answer 18

• Exercise intensity
• Exercise duration
• Preceding diet
• Training status
• Plasma FFA (fatty free acids) concentration
• Endogenous and exogenous CHO availability

Question 19

at rest what % of energy expenditure is due to fat oxidation

Answer 19

~50%

Question 20

at 25% of VO2 max what % of energy expenditure is due to fat oxidation

Answer 20

~80%

Question 21

at 65% of VO2 max what % of energy expenditure is due to fat oxidation and what is increased

Answer 21

~50%
increased intramuscular triglyceride use

Question 22

at 85% VO2 max what % of energy expenditure is due to fat oxidation and what is decreased

Answer 22

~ 25%
decreased plasma free fatty acids and intramuscular triglyceride use