Lecture Slides - Lipids II Flashcards
Where is the most abundant availability of substrate energy CHO in the body? Lipids?
CHO are most available in muscle glycogen and lipids are most abundant n the adipose tissue.
What are the 6 potential limits of fat oxidation?
- Lipolysis
- Removal of FA from the fat cell
- Transport of fat in the blood
- Transport of FA into the muscle fibers
- Transport of FA into mitochondria
- Oxidation of FA in the beta-oxidation pathway and TCA cycle
“breakdown of TG into FA and glycerol”
lipolysis
At approximately what intensity is fat oxidation highest at during exercise? When does it start to drastically drop?
60-65% ; approx 75%`
At 25% VO2 max, where is most of the substrate utilization from?
Plasma Fatty Acids
At 86% VO2 max, where is most of the substrate utilization from?
muscle glycogen
Ketogenic diets are characterized by low ____ and high _____ intake
low CHO and high fat
since the 1960’s, ketogenic diets have been used as an adjunctive therapy for _______
epilepsy
“Classical” model for a ketogenic diet:
- ___% fat
- ___% CHO
- ___% protein
90
7
3
“Modern” model for a ketogenic diet:
- ___% fat
- ___% CHO
- ___% protein
60-70
20-25
15-20
Ketogenic diets tend to lack both _____ and _____
vitamins (C, A, ect.) and minerals (electrolytes, ect.)
What are 5 well established effects of ketogenic diets?
- hyperlipidemia
- coronary artery disease
- growth failure
- GI disorders
- nephrolithiasis
negative performance effects may occur in high fat (ketogenic) diets of > __ wks and 1 week of ___ ____ is not enough to reverse it
4 ; high CHO
Why might training be compromised while on a high fat (ketogenic) diet?
due to low glycogen stores
T/F: A ketogenic diet can be psychologically stressful
true
What effects did the Burke et al. 2017 article find about the low CHO high fat (LCHF) diet on performance?
The LCHF diet increased oxidation, but also increased the O2 cost of exercise - the change in exercise economy negated any performance improvement
Beta-hydroxybutyrate is the primary human ketone. It is synthesized in the ____ from _____.
liver from acetoacetate
When is Beta-hydroxybutyrate used as an energy store?
by the brain when blood glucose is low
When you test a patients urine or blood for ketones, what are you looking for?
to see if they are in ketoacidosis
In what state is Beta-hydroxybutyrate produced in greatest concentration?
alcoholic ketoacidosis
When does alcoholic ketoacidosis occur?
occurs if oxaloacetate in the liver cells is depleted
Under which three circumstances can oxaloacetate in the liver cells become depleted?
- reduced CHO intake (though diet or starvation)
- prolonged, excessive alcohol consumption
- insulin deficiency
In epilepsy patients on the ketogenic diet, blood _____ levels correlate best with degree of seizure control
Beta-hydroxybutyrate
