Fat Intake and Supplementation Flashcards
What is the process called where 3 fatty acids react with a glycerol molecules to produce a triglyceride
Esterification
What does esterification form?
triglyceride
water
Are short chain FFAs more liquid or solid
Liquid
Are long chain FFAs more liquid or solid
Solid
Saturated FAs have what type of carbon bonds
Single carbon bonds
Unsaturated FAs have what type of carbon bonds
Double carbon bonds
Which type of FA stimulates liver to form cholesterol
Saturated
Which type of FA can be mono or poly
Unsaturated
What does Trans FAs occur as a result of
Processing- e.g. heat and light
Define essential FA
must be obtained from the diet
Give an example of an essential FA
Omega 3,6 or 9
Define non-essential FA
can be synthesised endogenously
Give an example of a non-essential FA
Any fat that isn’t an omega one.. i.e. palmitate
By what process does fat travel through the phospholipid bilayer?
Facilitated diffusion
If there is higher levels of n-3 PUFA, how does this effect the production of intracellular mediators
Less inflammatory mediators
Define adipose tissue
A store of fat for energy in the fasted state
What type of cytokines are produced by adipose tissue
Pro-inflammatory cytokines
Give 3 examples of hormones secreted by adipose tissue
Leptin Adiponectin ADMA Angiotensin 1/II Oestrogen
How are lipoproteins transported in the blood
in chylomicrons
Describe the transport of fat
Lipid in GI tract –> chylomicron –> lipoprotein lipase –> HDL (extrahepatic) or LDL (liver) –> cholesterol
Describe simply glycolysis (with fat) steps
Glucose –> pyruvate (–> lactate) –> PDC –> acetyl-CoA –> acetyl carnitine –> B-oxidation
Describe simply long-chain fat oxidation steps
LCFA –> Acyl CoA –> CPT1 + CACT + CPT2 –> acyl-CoA –> B-oxidation
What are the most immediately available form of lipid
Intramuscular triglycerides
What is the athlete’s paradox (fats)
large lipid droplets, close to the mitochondria are beneficial to performance.
There is a U Shape where both an athlete and T2D have high IMCL, but athletes have a high oxidative capacity and insulin sensitivity
What is the approximate maximum oxidation % for fats to be effective at
65-70%
what is the process called where TG’s are changed to FAs, and what hormone is used
lipolysis + Hormone sensitive lipase
Give a hormone which increase the activity of HSL
Adrenaline/Noradrenaline
Give a hormone which decreases the activity of HSL
Insulin
Do type 1 or 2 fibres have a higher density of fatty acid transporters
Type 1
Why do type 1 fibres have a higher density of fatty acid transporters
Type 1 fibres are the predominant site of fat oxidation. They can oxidise the FA, transport it to tissues, and to the cells
Give an example of a key fat transporter
CD36 or CPT1
Where is the greatest site of FA oxidation limitation A) Extracellular B) Intracellular C) Mitochondria D) Serum
B) Intracellular
Give 2 factors which regulate fat oxidation
- Fat availability
- Transport into cell
- Oxidative capacity
Why would a trained athlete use fat preferentially
Spare endogenous glycogen stores
What is the drug co-infused with fat to aid digestion and absorption
Heparin
Which hormone does heparin target
Lipoprotein Lipase release
Costill et al., found that pre-exercise fat feeding increased fat oxidation, and decreased CHO (with heparin). What happened when this was repeated without heparin?
Fat oxidation wasn’t stimulated. Ingested long chain fats were inefficiently oxidised, long/medium didn’t impact plasma FFAs- so can’t increase ffa availability.
True or false: Medium chain triglycerides are Independent of the carnitine shuttle
True
What was the difference between a 3 and 7 day high fat diet results
A 3 day high fat diet showed favourable changes -an adaptive response: CHO oxidation decreased, and fat oxidation increased at a moderate-high intensity.
A 7-day high fat (low CHO) diet showed this impaired glycogen and IM fat stores, which has performance implications. Further negative effects on metabolism and performance due to reduced glycogen storage
If fat intake is too low, there is progressive depletion of what
IMTG stores
Higher fat content generally leads to lower what
muscle glycogen storeage
High fat and high CHO diet increased levels of what
Ketones
What are ketones
byproducts of the body breaking down fat for energy that occurs when carbohydrate intake is low
Why are ketones bad
Increase RPE and can cause ketosis at elevated levels
Why does high habitual fat intake reduce glycolysis
habitual enzymes are shifted from CHO to fat
