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Fats as Fuels during exercise
Chapter 4
Where are lipids found?
Butter, margarine, gravy, saucesmeats, poultry,eggs, bacon,ham,&sausage
fried fishdaily products including milk, cheeseprocessed foods including potato chips.
French fries, crackers, bakery products like cookies, cakes, muffins,
pies, bars, breakfast rolls
Fats sources continued
Nuts such as peanuts and peanut butter, cashews, walnuts
seeds like sunflower seedsolives and avocadoscandies with chocolate and nuts
Are their foods without fat?
Fruits, fruit juicesvegetables, including potatoesbreads, breakfast cereals, sugar, salt, spices herbsskim milkrice, macaroni, pasta
Does preparation methods effect fat content?
Baking, broiling, boiling, poaching, do not add fat
frying doesbaked potato vs. french fried potatobaked fish vs. deep fried fishpoached egg vs. fried egg
Does margarine have less fat than butter?
NObutter and margarine both have 5 grams of
fat per teaspoondiet margarine has less fat because water is
added
Does all meat have equal amount of fat?
NO you can lower the fat content by removing all
visible fat BEFORE cookingpurchase cuts with the word LOIN in them
such as sirloin, tenderloinstay away from PRIME cutsstay away from processed meats such as cold
cuts and hot dogs
Is poultry low fat?
Yes, if the skin is removed before cookingpoultry generally has 3 grams of fat per
ounce as compared to other meats with 5 to 8 grams of fat per ounce.
Stay away from broasted chicken or deep fried
How about salad dressings?
Most salad dressing are high in fat mayo is also high in fatfat-free dressings are a good choiceif using regular salad dressing do not pour
on salad, dip the fork in the dressing and than take a bite of salad. Gives the taste with less fat
Meal extras are high in fat
Bacon has 5 grams of fat per strippeanuts are app. 1 gram per peanutpeanut butter has 100 calories and 10 -18
grams of fat in a 2 tbsp serving.Cheddar cheese, swiss cheese, american
cheese have 8 grams of fat per ounce
Should all fat be eliminated from the diet?
Nothe body needs fat for many functions1. Energy2. Insulation3. Protection of vital organs4. Carrier of fat soluble vitamins5. Cholesterol for hormones & cell structure
The key is moderation in the amount eaten daily
Average intake is 40% of calories coming from fat
healthier to have only 30% coming from fat
Calculate the number of grams of fat needed daily
1. Determine the number of total kcalories needed
2. Multiply the total kcalories time 30% (.30)
3. Divide the answer from step 2 by 9kcalories/gm to determine the number of grams needed daily
Example of the calculation
Total kcalories = 1500kcals1500kcals X .30 = 450Kcals450kcals divided by 9kcals/gm = 50 grams50 grams is app 10 tsp daily from all
sources
Are all fats equal in causing risk?
In heart disease the most dangerous fat is saturated fat
in obesity all fats have 9kcals per grams so total fat is the problem
cancer all fats seem to be a problem
Types of Dietary Fat
1. Triglyceride - 95% of dietary fat is in this form
2. Phospholipids - 2.5%3. Sterols - 2.5%
Triglycerides
Found in most fatty foods like meats, oil, butter, eggs, pastries etc.
consists of 4 parts glycerol fatty acid fatty acid fatty acid
Kinds of Fatty acids
Saturated fatty acids - stearic or palmiticgenerally solid at room temperaturegenerally found in animal foods including1. Beef2. Pork3. Lamb4. Milk, cheese, butter, cream
Other sources of saturated fatty acids
Non-animal sources1. Chocolate2. Coconut oil3. Palm oil4. Hydrogenated shortening5. Hydrogenated peanut butter
Monounsaturated Fatty Acid
Generally found in plant foods like1. Olive oil2. Canola oil3. Peanut oil4. Sesame oil
Monounsaturated Fatty Acids
Non-plant sources - chicken without the skin
usually liquid at room temperaturestructure has one-double bondoleic is an example of a monounsaturated
fatty acid
Polyunsaturated Fatty acids
Generally of plant origin 1. Corn oil2. Safflower oil3. Sunflower oil4. Soybean oilnon-plant sourcefish
Polyunsaturated fatty acids
Usually liquid at room temperaturehave more than one double bondexamples of fatty acids are1. Linolenic2. Linoleic
Triglycerides
Storage form for metabolizable fatty acids & glycerol
stored in fat cells and muscle cellsmuscle triglyceride available for immediate
workfat cell triglyceride must be moved to where
needed to be metabolized
Triglycerides continued
Hydrolysis breaks down triglycerides into free fatty acids- Krebs cycle
training increases the muscle ability to use fats- highly trained athlete at 70%VO2 Max for 1 hour can derive up to 75% of total energy from fat
The degree to which lipids are used as a fuel during exercise is:
Exercise intensityexercise durationdietendurance training historyaltered metabolic state
Exercise & fat continued
Exercise less that 50% VO2 Max uses Type I muscle - these burn fatty acids
increased intensity relies on type IIA & B which use more glucose
training increases number of mitochondria in cell and enzymes involved in fatty-acid oxidation- more burning of fat as energy source
Carnitine
Transports long-chain fatty acids across the mitochondrial membrane
made from amino acids lysine and methionepresent also in foodsclaim is that increases the burning of fat in
the mitochondria. Only would be true if deficient which is not likely
Medium Chain Triglycerides
Water solubledelivered directly to livermarketed as CaprTri. Studies show does not improve
performance and may cause GI distressfat loading does not enhance performance
Fat loading & glycerol
Fat loading does not improve fatty acid content of the blood or the muscle and that loading does not improve performance
glycerol does breakdown into glucose but does not prevent hypoglycemia or spare muscle glycogen
glycerol may have a role in water stores
Families of Polyunsaturated Fatty Acids
Omega 6 - first bond occurs at carbon number 6 found in large amounts in vegetable oil
omega 3 - first double bond occurs at carbon number 3 found in fish
Eicosanoids
Hormone-like compounds formed from 20 carbon fatty acids
two major types of eicosaniods1. Made from omega 62. Made from omega 33. Theories that might improve
performance but not proven in research
Omega 6 eicosanoids
Made from the 18 carbon fatty acid linoleic under goes chain lengthening to become the
20 carbon fatty acid archidonicarchidonic( 20 carbon) can then be used to
make the eicosanoidthis eicosanoid is used by the body to
increase blood clotting and increase blood pressure
Omega 3 ecosanoid
Made from 18 C linolenicundergoes chain lengthening to become 20C f
s atty acid Eicopentenoic acid (EPA)EPA is than used by the body to make the
omega 3 eicosanoidthe omega 3 eicosanoid decrease blood clotting
and increase blood pressurefish is rich in EPA
EPA sources
Herringwhite albacore tunasalmonlake troutfish needs to be an oily fishfish oil DOES NOT work
Summary
Classes of Lipids1. Triglyceride - 3 fatty acids + glycerolKinds of fatty acids
saturated monounsaturated polyunsaturated
summary
Kinds of polyunsaturated1. Omega 32. Omega 6
Second class of lipids - phospholipids
Consist of glycerol plus 2 fatty acids and a third group containing phosphorus
most common - lecithin - found in chocolate and salad dressings - emulsifier
theory that choline and lecithin improve performance - not supported by research
Third class of lipids - sterols
Ring sturcturemost common cholesterolsources of cholesterol1. Egg yolk2. Organ meats - liver brains3. Red meats, shellfish
Wheat Germ Oil
Extracted from embryo of wheathigh in Vitamin E (tochoperol)linoleic fatty acidoctacosanol solid white alcoholresearch show does not improve
performance
Caffeine
Found in coffee, tea cola, chocolatetherapeutic dose 100-300 mgamount in 1 cup of coffee 100-150 mgamount in pop 35-50highest amount in soft drinks such as
Mountain dew
Caffeine
Stimulates CNSincreases alertness stimulates heart, circulation and release of
adrenalineincrease muscle glycogen breakdown,
release of FFA from fat and muscle use of fat
Caffeine
Large does cause nervousness, and anxiousness
caffeine does exert a glycogen sparing effect in research studies
limits are set - max is 560-700 mg which is equal to 4-6 cups of coffee.
Digestion of the triglyceride
Begins in the stomachmost occurs in the small intestine- hormone
cholecyctokinin (cck) produced in the intestine by fat - stimulates the gall bladder to release bile - bile emulsifies the fat- than acted upon by lipase from the pancrease - break down 3 fatty acids + glycerol
Fatty acids leave blood
Transported in the blood in a Lipoprotein called CHYLOMICRON - contains mostly trigylceride from the diet -
as chylomicron goes by cell - release lipoprotein lipase and the cell can than take the triglyceride which can be used for energy or stored as body fat.
Lipoproteins made by the liver
Very low density (VLDL) - made by the liver from excess CHO, alcohol - most triglyceride-
low density lipoprotein (LDL) - contains cholesterol made by the liver from saturated fatty acids BAD CHOLESTEROL
High density lipoprotein - GOOD CHOLESTEROL - return cholesterol to liver
To prevent artherosclerosis decrease LDL & increase HDL
HDL1. Exercise - 45 min 4 times / week 2. Don’t smoke3. Use monounsaturated fatty acids4. Low fat5. Weight loss around the middle6. Moderate alcohol-10 oz wine,24oz beer
maximum
Decrease LDL
Reduce fatreduce saturated fat 7-10%low cholesterol - 300 mgweight lossincrease soluble fiber (oat bran,
fruits,vegetables)
Risk Factors
Total cholesterol over 200mgLDL over 130mg - (100 is ideal)HDL under 35mg - (60 or greater greater)age over 45 in men and 55 in womenfamily history - smokinginadequate intakes of folic acid, B-6high blood pressure - diabetes
continued
Composition of lipoproteins & origin disease linked to fat intakekcalories in fat and in body fatamount of recommended lipids in the dietcalculate amount of fat in the diet and the per
cent of dietary fat. Remember that all fats regardless of saturation have 9 kcals/gm