Lecture 5 Flashcards
What are the 3 classes of fats
- triglycerides
- phospholipids
- cholesterol and other sterols
Functions of triglycerides
- energy source
- physical and thermal insulator
- carrier of fat soluble vitamins
Functions of phospholipids
- cell membrane structure
- emulsifier (fat digestion and fat transport in blood)
Functions of cholesterol
- cell membrane structure
- pre-curser for: bile acids, steroid hormones, vitamin D
- sources: animals fats only, made in the liver from SFA
Poly-unsaturated fats
- lowers LDL cholesterol
- may slightly lower HDL cholesterol
- dietary sources: veggie oils, fish oils
What are the 2 essential fatty acids
- omega 6 (linoleic acid)
- omega 3 (linolenic acid)
Saturated fats
- can increase the risk of heart disease
- ex. butter, cakes, pastries, chocolate bars, coconut
Saturated Fatty Acids
- raise blood cholesterol
- solid at room temperature
- high in animal fats (coconut, palm, cocoa)
Monounsaturated fats
- considered “good” fats because they help decrease the risk of heart disease
- lower blood cholesterol (lower LDL but no effect on HDL)
- ex. olive oil, canola oil, margarine made with canola, peanuts, nuts
Trans fats
- made from hydrogenation
- acts like saturated fats in the body
- most found in commercially prepared foods
Natural occurring trans fats
-found in dairy and meat
What are the 2 types of naturally occurring trans fats?
- conjugated linoleic acid
- trans vaccenic acid
What does conjugated linoleic acid do?
-may reduce risk of cancer and heart disease
What does trans vaccenic acid do?
- may reduce risk of heart disease
- converted to conjugated linoleic acid in the body
What are the health concerns of trans fatty acids?
- risk of CHD
- increase LDL-C by decreasing LDL receptor activity
What are the 4 mechanisms through which fat metabolism could be manipulated to spare glycogen?
- training methods
- MCT feedings
- high fat training diets/fat loading
- supplements (L-carnitine and caffeine)
How many fatty acids do MCT’s contain?
6-10
Side effects of MCT Feedings
diarrhea, vomiting, irritability, nausea, stomach discomfort, intestinal gas
Theory behind L-carnitine supplements
because l-carnitine is involved in the transfer of LCFA across the mictochondrial membrane, supplement with L-carnitine could enhance FA oxidation in athletes
How does caffeine enhance
- alters the athletes perception of effort as a result of its impact on the CNS
- alters levels of key enzymes in skeletal muscle to down regulate carb breakdown
- enhance fat oxidation and decreasing carb utilization
What is hydroxycut?
-popular weight loss supplement that claims to burn fat through the action of caffeine
Consequences of Inadequate Fat Intakes in athletes
- can present risks to sport performance and health
- might not have enough fat to fuel sport performance
- might not be able to support fat soluble vitamins
- inadequate in total energy and over emphasize other macronutrients
- may promote nutrients deficiencies
- may alter reproductive hormone levels and disrupt reproductive functioning in both men and women
