Fat metabolism Flashcards
What factors influence the rate of fat oxidation during exercise?
- training status
- lean body mass
- physical activity level
- sex
- nutrition
- type of exercise
When is the best time to maximize fat oxidation? And why?
Exercising in the fasted state (first thing before breakfast).
Fasted exercise can effect metabolism for the next 24 hours post.
Why are high GI foods avoided during weight loss?
High GI foods greatly increase blood glucose levels which increases insulin levels. This suppresses the body’s ability to metabolize fat.
Give an example of a high GI breakfast and a low GI breakfast
High GI - cornflakes and toast
Low GI - muesli and yoghurt
Why are low GI foods good to consume pre-exercise?
You utilize more fat oxidation compared to CHO oxidation for energy
Why might calcium be good for fat metabolism and weight loss?
- High calcium intake impairs dietary fat absorption through the formation of insoluble calcium soaps
- Calcium MAY influence appetite regulation
- Calcium suppresses parathyroid hormone which increases FFA availability for oxidation
What would you recommend to consume to increase calcium?
Yoghurts, dairy etc.
NOT supplements - proven to be ineffective on fat metabolism
What is the role of carnitine in the muscle?
- long chain fatty acid translocation into the mitochondria
- buffer for excess Acetyl-CoA production during HI exercise
Under what condition is muscle carnitine uptake possible?
high insulinaemia - carnitine infused with big dose of CHO
Why is carnitine not used for increasing fat metabolism?
Takes a huge amount of CHO and prolonged carnitine intake to have any effect (24 weeks)
What does fish oil supplements reduce? And why?
Postprandial lipaemia possibly due to an increase in muscle lipoprotein lipase activity
