Dietary Fat And Exercise Flashcards
How fats act in body (energy)
Glycogen sparing/training effect
Fatigue reduction
Energy dense (9kcal/g)
Low TEF (low energy cost for digestion/storage)
How fats act in body
Efficient storage (stored with little water)
Slow gastric emptying
Increased satiety
Food enjoyment
Fat soluble vitamins
Essential fatty acids (EFA)
What vitamins need fat to be absorbed
A,D,E,K
What are fats we need to eat that body doesn’t make
Essential fatty acids
What is fat primary fuel for
Light-mod exercise
How many total body calories in adipose tissue triglycerides
80,000
How many total body calories in muscle triglycerides
2,500
Lipids
Dietary fat, insoluble to water
- carbon, hydrogen, and oxygen
Triglycerides makeup
Glycerol backbone
3 fatty acids attached to each glycerol
What is broken down on triglycerides
Fatty acids broken down for energy
3 types of lipids
Triglycerides
Phospholipids
Cholesterol
Fat products
Animal products (fish very fatty), avocado, nut, seeds, whole grain, salad dressing, butter, mayo
ADMR for fat
19+: 20-35%
What is there none of for fat
RDA, AI, or UL, except for infants
What is there none of for fat
RDA, AI, or UL
What do dietary fats have
Different lengths and degrees of saturation
What is EAR for
Population (50 yr olds in America)
What is RDA for
One specific 50 yr old man
Where do we want most fats to come from
Unsaturated FAs
Breakdown for recommended intake
Saturated FAs 10%
- minimize trans fat
- max 7-10% from saturated and trans
Monounsaturated FAs 10%
Polyunsaturated FAs 10% (linoleic acid and a-linolenic acid)
Consuming <20% fat
Does not benefit performance
What is not recommended for performance based training sessions or competitions
High fat or low fat diets
Factors to consider for fat intake for athletes
- type of sport- training demands, energy systems used
- overall health
- performance
- body composition goals/ weight class
- time of competitive session/periodized nutrition
- training volume
Esterification (fat formation)
Formation of TG
- combination of an acid and alcohol (glycerol)= ester
When is the process of fat formation favoured
After eating a meal
- when body receives fatty acids and glucose
Fat lipolysis (TG lipolysis or hydrolysis)
Breakdown of TGs to yield energy (ATP) from FAs and glycerol
What happens to glycerol when broken down from TGs
To liver to make glucose
Breakdown (hydrolysis) favoured during
- exercise
- low calorie dieting/low energy availability
- fasting or starvation
- decreased insulin concentrations (CHO not present)
- increased growth hormone, cortisol and catecholamines (fight or flight)
- when body is cold
Lipolysis involves
3 hydrolysis reactions
What are the 3 hydrolysis reactions catalyze by
Hormone-sensitive lipase (HSL)
- Enzyme (breaking down)
2 major fates of fat after lipolysis
- re-esterification to TG (storage of fat)
- exit from fat cell (free FA, or attach to albumin)
Beta oxidation
Metabolism of fatty acids into acetyl CoA
How is acetyl CoA processed
Via Krebs cycle and electron transport system to produce ATP
At rest how much energy supplied by metabolism of fats
Nearly 60% (when consuming mixed diet)
At rest what is happening to FFAs?
Constantly being mobilized from adipose tissue to replenish plasma FFA
How many FFA released get re-esterfied back into TGs
70% and remainder delivered to body cells for energy
What are 2 major sources of ATP for exercise
CHO and fat
What kind of fat is metabolized during exercise
Free fatty acids - mainly long chain fatty acids (LCFA)