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302 Cards in this Set
- Front
- Back
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Nutrients |
Substance in food that performs one or more functions in the body |
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Macronutrients |
Carbohydrates, fat, protein, water |
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Micronutrients |
Vitamins, minerals, trace elements |
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What are nutrients for? |
Growth and development Energy Metabolism |
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What do Macronutrients do? |
Provide energy, maintain structure, and provide functional integrity |
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Carbon |
Component of all nutrients, except for water and minerals. Binds with hydrogen, oxygen, and nitrogen to form CHO, FAT, and PRO. Vitamins are also carbon based |
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What are the different types of carbohydrates? |
- Simple (Monosaccharides & Disaccharides) - Complex (Polysaccharides - ie chains of sugar molecules, such as glucose) |
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What are the different types of monosaccharides? |
-Glucose (C6H12O6) -Fructose (C6H12O6) -Galactose (C6H12O6) -Each has a unique atomic arrangement giving them different biochemical properties. -Can also be broken down into trioses or pentoses to combine with other nutrients to create glycoproteins (which act as receptors in cell membranes) or glycolipids. |
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Glucose |
Also Called dextrose or blood sugar. A monosaccharide Used directly for the cell for energy. Stored as glycogen in muscles and liver for later use. Converted to fat and stored for energy |
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Fructose |
A monosaccharide Also known as levulose or fruit sugar. Liver converts this to glucose. |
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Galactose |
A monosaccharide Forms milk sugar called lactose Body converts this to glucose for energy metabolism |
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Disaccharides |
The combination of 2 monosaccharide molecules. Each molecule includes glucose as a principle component. ie Sucrose = glucose + fructose Lactose = glucose + galactose Maltose = glucose + glucose |
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glucose + glucose = |
Maltose |
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glucose + galactose = |
Lactose |
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glucose + fructose = |
Sucrose |
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Oligosaccharides |
3 to 9 monosaccharides linked together Uncommon in the diet. Usually found in dried beans and low-calorie foods. Difficult to digest, but are broken down by bacteria in the intestines |
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Polysaccharides |
Can be divided into 2 main groups: Digestible and indigestible |
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Digestible polysaccharides |
Include starch and animal glycogen. Starch: common term is "complex carbohydrate". ie seeds, rice, corn, grains, potato. Have amylose or amylopectin (straight or branched chains. |
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Starch |
A digestible Polysaccharide Common term is "complex carbohydrate". ie seeds, rice, corn, grains, potato. Have amylose or amylopectin (straight or branched chains. |
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Fiber |
An indigestible polysaccharide These materials resist hydrolysis by human digestive enzymes due to their beta - 1,4 linkages. Can differ wildly in physical and chemical characteristics. ie water soluble gums and pectin vs water insoluble cellulose, hemicellulose, and lignin |
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What are the roles of soluble fiber? |
Reduces gastric emptying and slows glucose absorption in the small intestines, leading to satiety and more controlled blood glucose levels Retains water and gives "bulk" to the food residues in the intestines. Binds or dilutes harmful chemicals, such as carcinogens May reduce cholesterol and risk of high blood glucose Fermented by bacteria in the large intestine to produce short chain fatty acids, which have been shown to reduce cholesterol, coronary artery disease, and "bad" intestinal bacteria |
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What are the roles of insoluble fiber? |
Acts as a scrubber that scrapes the cells of the gut walls Also provides bulk and stimulates peristalsis in the intestine Shortens transit time for food residues (and carcinogenic materials) to pass through the digestive tract. |
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What is the recommended fiber intake for men and women? |
Women: 25g/day Men: 38g/day |
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What is the recommended carbohydrates intake per day? |
At lease 130g/day, but ideally closer to 50-60% of total energy intake. This depends on activity level and type of activity. |
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How are polysaccharides stored in mammalian muscle and liver tissue? |
As glycogen. |
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How is glycogen synthesized from glucose? |
Via glucogenesis |
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Glycogenolysis |
The break down of glycogen to glucose for rapid extramuscular glucose supply. Takes place in muscle or liver |
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Glycogen |
A polymer of glucose Multiple branches allows the glucose molecules to be cleaved in several area at once, causing a rapid release of energy to occur. |
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Gluconeogenesis |
Creation of glucose, using the carbon skeletons from glycerol (from triglycerides) or amino acids |
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What hormones regulate blood sugar |
Insulin and glucagon |
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Insulin |
Helps regulate blood sugar Enables peripheral tissues to take up glucose (reduces blood sugar) |
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Glucagon |
Hormone for regulating blood sugar Stimulates liver glycogenolysis and gluconeogenesis Raises blood sugar |
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What are the functions of carbohydrates? |
1) Energy Source: Primary fuel for the body, especially during high-intensity exercise 2) Adequate intake preserves tissue proteins: low glycogen levels cause protein (from muscles) and fat to be broken down to provide energy for the body. 3) Metabolic primer/prevents ketosis: Low glycogen levels cause increased incomplete fat breakdown producing ketone bodies. Ketosis can begin after just 24 hrs of starvation 4) Fuel for the CNS and red blood cells: CNS relies of CHO for energy, but can also use ketones when necessary (however this can cause brain damage!). Brain uses ~120g CHO/day |
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Glycemic Index |
A classification method based on the effect of food on blood glucose levels Used for diabetes counseling Can be useful for athletes to use in choosing CHO sources for different purposes Generally, higher fiber foods have a lower GI index. |
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Lipid |
General term for a heterogenous group of compounds (oils, fats, waxes, and related compounds). These molecules contain the same structural elements as CHO, but are lower in oxygen molecules. |
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What are the three main groups of lipids? |
1) Simple lipids: neutral fats, primarily triaglycerols. Major storage form of fat in adipose cells. 2) Compound Lipids: Consist of a triacylglycerol molecule combined with other chemicals. 3) Derived Lipids: Formed from simple and compound lipids. Contain hydrocarbon rings (ie cholesterol) |
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Simple lipids |
Neutral fats, primarily triaglycerols. Major storage form of fat in adipose cells. |
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Compound Lipids |
Consist of a triacylglycerol molecule combined with other chemicals. |
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Derived Lipids |
Formed from simple and compound lipids. Contain hydrocarbon rings (ie cholesterol) |
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Triglycerides |
Glycerol - a 3-carbon alcohol molecule Three clusters of carbon-chained atoms, fatty acids, attach to the glycerol molecule to form a triglyceride Most dietary and storage fat is in this form |
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Saturated fatty acids |
Contain only single covalent bonds between carbon atoms. The remaining bonds attach to hydrogen atoms. |
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Trans fatty acids |
Contain trans double bonds which are structurally similar to single covalent bonds. These trans bonds are created when unsaturated fatty acids are hydrogenated and their double bonds change from cis to trans. |
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Unsaturated fatty acids |
Contain one or more double bonds (cis) along the main carbon chain Monounsaturated fatty acids contain one double bond Polyunsaturated fatty acid contains two or more double bonds |
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Short-chain fatty acids |
C6 chain length or less |
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Medium chain fatty acids |
C8-C10 chain length |
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Long-chain fatty acids |
C12 or more (these are the most abundant) |
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Oils |
Exist as liquids and contain unsaturated fatty acids Hydrogenation changes these to semisolid compounds Omega-3 family of fatty acids: These oils are characterized by the presence of a double bond 3 carbons from the 'n' end of the molecule |
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Omega-3 family of fatty acids |
These oils are characterized by the presence of a double bond 3 carbons from the 'n' end of the molecule |
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Omega-6 family of fatty acids |
These oils are characterized by the presence of a double bond 6 carbons from the 'n' end of the molecule |
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Essential Fatty acids |
Fatty Acids that the body cannot sythesize ex. Linoleic Acid, Alpha-linolenic acid(for EPA and DHA) |
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"Good Cholesterol" |
High Density Lipoprotein (HDL) |
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High Density Lipoprotein (HDL) |
Contains more protein and less lipid and cholesterol than the other lipoproteins. Removes "bad cholesterols" (LDL) from arterial walls. |
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"Bad Cholesterol" |
Low density lipoprotein (LDL) or Very low density lipoprotein (VLDL) |
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Low density lipoprotein (LDL) |
Carries the most cholesterol and has the greatest affinity for cells of the arterial wall. |
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Very low density lipoprotein (VLDL) |
Contains the greatest percentage of lipid, primarily triglycerol. |
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What are the roles of lipids? |
1. Provide energy: fats are the main source of energy at rest 2. Protect vital organs 3. Provide insulation 4. Transport the fat-soluble vitamins A, D, E, K 5. Cell membrane structure 6. Hormones |
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What are the forms of lipids that are used as fuel? |
Fatty acids, intramuscular triacylglycerols, and plasma triacylglycerols |
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What is the main form of transportation of triacylglycerols from the liver to adipose and muscle cells? |
VLDLs |
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What is the main transport of cholesterol from the peripheral tissues to the liver? |
HDL |
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What is protein formed from? |
Amino acids. |
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Amino acids |
Each have an amino group (NH2) and an acid group (COOH). The remainder of the molecule is known as the side chain. Peptide bonds link these to make diverse forms and chemical combinations. |
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Side Chain |
The remainder of an amino acid after excluding the amino group and the acid group. The unique structure of this dictates the characteristics |
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Deamination |
Breakdown of amino acids. Byproduct of NH2 - converted to ammonia in the liver and then into urea. Eliminated through the urine. |
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Deamination leaves what compound? |
Alpha-ketoacid |
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Alpha-ketoacid |
Created through deamination. Can be used for: energy, reconstitution of other amino acids, or used in metabolic pathway to be turned into glucose or fat. |
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How many amino acids does the body require? |
20 different total amino acids. 8 amino acids are essential and cannot be synthesized in the body. All other amino acids can be synthesized in the body using the essential amino acids. |
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Essential amino acids |
Cannot be synthesized in the body. Must be taken in through diet. 8 in total: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine |
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Dipeptides |
two amino acids connected via peptide bonds |
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Tripeptides |
3 amino acids connected via peptide bonds |
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polypeptides |
50-100 amino acids connected via peptide bonds |
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Protein |
> 100 amino acids connected via peptide bonds |
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Complete Proteins |
High-quality protein Contain all essential amino acids in the quantity and correct ratio to maintain nitrogen balance and allow for tissue growth and repair. Come from animal sources mainly. Plant sources are soy beans and quinoa. |
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Incomplete protein |
"Low-quality protein" Lacks one or more essential amino acids Plant sources These typically have a 'limiting amino acid' which is the amino acid in limited supply. Can be combined in diet to become equivalent to complete proteins. |
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What are the roles of protein? |
1. Hormone and neurotransmitter function: Proteins in nervous and connective tissue generally do not participate in energy metabolism. 2. Energy function: The amino acid alanine plays a key role in providing carbohydrate fuel via gluconeogenesis during prolonged exercise. The alanine-glucose cycle accounts for up to 40-50% of liver's glucose release during long-duration strenuous exercise. 3. Structural Function: In all cells, such as contractile muscle proteins. 4. Transport Function: Transports substances in the blood, such as lipoproteins. 5. Enzyme Function: Forms enzymes to assist in metabolic processes 6. Immune Function: Forms antibodies 7. Fluid balance function: Creates osmotic pressure in the body 8. Movement Function: Structural muscle proteins contract. |
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Kwashiorkor |
Deficiency in protein only. Large belly, often with edema |
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Marasmus |
Protein-energy deficiency (muscle wasting) |
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Does protein excess cause kidney damage? |
No, unless pre-existing kidney conditions exist |
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When does protein catabolism accelerate? |
During exercise as carb reserves deplete. Important for athletes who train vigorously to maintain optimal levels of muscle and liver glycogen to minimize lean tissue loss and deterioration in performance. |
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What are the protein requirements? |
Generally - 0.8-1.2 g/kg body weight Varies with age, activity level, disease states, pregnancy Can be up to 2.2-2.3g/kg body weight max |
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What percentage of the body is water? |
40-70% of total body mass |
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How much water does muscle contain? |
72% |
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How much water does fat contain? |
50% |
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How much water is intracellular? |
62% |
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How much water is extracellular? |
38% between the plasma, lymph, and other fluids |
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Does exercise training lead to increases in water intracellularly or extracellularly? |
Intracellularly due to increased muscle mass |
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How does acute exercise shift fluids? |
Shifts fluid from plasma to intersticial and intracellular spaces die to increased fluid pressure in the circulatory system. |
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Where does the average daily water intake come from? |
Liquids: ~1.2 L Food: ~ 1.0 L Metabolic Water: ~0.3 L |
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Where does the daily water loss come from? |
Urine: ~1-1.5 L Insensible Perspiration: ~ .5 - .7 L Water vapor in expired air: ~ 0.25 - 0.3 L Feces: ~0.1 L |
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EUHYDRATION |
Normal daily water variation |
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Hyperhydration |
Condition of the body retaining excess fluids |
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Hypohydration |
Condition of decreased water content and a low body water level |
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Dehydration |
Loss of body water |
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Rehydration |
Process of gaining water |
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What happens when weight is decreased by 3% due to dehydration? |
Reduced exercise performance |
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What happens when weight is decreased by 5% due to dehydration? |
Confusion, disorientation |
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What happens when weight is decreased by > 10% due to dehydration? |
Life threatening |
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What are the roles of water? |
1. Provides Structure: Essential building material for cell protoplasm 2. Protects spinal cord and brain due to resistance to compression 3. Regulates Body Temperature: Sweat is mostly water. Via evaporation on the skin, the body's heat dissipates 4. Provides a medium for substances to interact chemically 5. Transports oxygen, nutrients, hormones, and other essential compounds to cells. Also carries waste products away from cells for excretion. 6. Controls osmotic pressure: Balances electrolytes 7. Can reduce risk of certain cancers (bladder, colon) and can probably flush carcinogens. |
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Vitamins |
Organic substances needed by the body in small amounts. Manufactured by plants during photosynthesis Have no particular chemical structure in common Often considered accessory nutrients |
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Fat-soluble vitamins |
A, D, E, & K |
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Water-soluble vitamins |
Vitamins C and B-complex Thiamine (B1), riboflavin (B2), pyridoxine (B6), niacin (nicotinic acid), pantothenic acid, biotin, folic acid, and cobalamin (B12) |
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What are the roles of vitamins? |
Serve as essential links and regulators in numerous metabolic reactions that release energy from food. Regulate metabolism Control process of tissue synthesis (bone formation, cell repair) Protect cell's plasma membrane |
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Free Radical |
Highly chemically reactive molecule that contains at least one unpaired electron in its outer valence shell Accumulation increases the potential for cell damage (oxidative stress) increasing the likelihood of cellular deterioration associated with aging, cancer, diabetes, CAD, and a general decline in CNS and immune functions |
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What vitamins particularly serve important functions as antioxidants? |
Vitamins A, C, E, and beta-carotene. Appropriate levels of these can reduce the potential for free radical damage, and may protect against heart disease and cancer. |
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Lycopene |
Main antioxidant in the body. Potent substance in carotene rich foods. Has been linked to reduced heart disease and reduced risk of developing several deadly forms of cancer. |
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Homocysteine |
All people produce this. Normally converts to other non-damaging amino acids. 3 B-vitamins - folate, B6, & B12 - facilitate the conversion If conversion slows due to vitamin deficiency, homocysteine levels increase and promote cholesterol's damaging effects on arterial lumen |
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What do fat-soluble vitamins do? |
Dissolve in fat and store in the body's fatty tissues. Can become toxic if consumed in excess Should not be consumed in excess without medical supervision. Deficiencies are rare. |
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Vitamin A |
Retinol is a pre-formed vitamin A and is a carotenoid. Some carotenoids cannot become vitamin A. Fat soluble vitamin Can be formed in the body using beta-carotene Food sources: Liver, butter, margarine, egg yolks, dark leafy vegetables, yellow-orange veggies, some yellow fruits Functions: Maintain epithelial cells, vision, optimal immune system function, antioxidant Deficiency: Night vision loss, increased infections, and skin lesions, blindness, reduced muscle synthesis, gluconeogenesis |
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Vitamin D |
In the body of animals it is known as "cholecalciferol" or D3. Plant sources are known as "ergocalciferol" or D2. Fat soluble vitamin Sources: Created when UV rays convert a compound in the skin to cholecalciferol. Diet sources includes eggs, fish, fish liver oils, and fortified foods such as milk, margarine, and cereals. Functions: Helps to absorb calcium from the GI tract and kidneys for normal serum calcium levels and bone metabolism, hormone function (parahormone in parathyroid gland), and phosphorous metabolism. Deficiency: Due to a lack of sunlight. Can cause osteomalacia (softening bones), muscle weakness, increased risk of some cancers, rickets Toxicity: Vomiting, diarrhea, weight loss, decreased muscle tone, calcium deposits Supplementation: Those lacking through diet or sun exposure are usually recommended to take 400 - 1000 IU |
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Functions of Vitamin A? |
Maintain epithelial cells, vision, optimal immune system function, antioxidant |
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Symptoms of deficiency of vitamin A? |
Night vision loss, increased infections, and skin lesions, blindness, reduced muscle synthesis, gluconeogenesis |
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Functions of vitamin D? |
Helps to absorb calcium from the GI tract and kidneys for normal serum calcium levels and bone metabolism, hormone function (parahormone in parathyroid gland), and phosphorous metabolism. |
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Symptoms of vitamin D deficiency? |
Due to a lack of sunlight. Can cause osteomalacia (softening bones), muscle weakness, increased risk of some cancers, rickets |
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What are the supplementation recommendations for vitamin D? |
Those lacking through diet or sun exposure are usually recommended to take 400 - 1000 IU |
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Vitamin E |
Most typical form is alpha-tocopherol Fat soluble vitamin Food Sources: Vegetable oils, margarine, fortified foods, dark leafy greens Functions: Antioxidant in cell membranes. Prevents oxidation of unsaturated fatty acids in phospholipids. Prevents chronic disease. Deficiency: Rare. Can cause anemia because reduced red blood cell integrity. Can also occur in heart disease. |
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Vitamin K |
Plays a role in coagulation. Fat soluble vitamin Food Source: soybean oil, olive oil, green leafy veggies, meats, milk. Also produced by bacteria in the large intestine Functions: Major factor in blood clotting. Enhances osteoclacin (improving bone strength.) |
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Functions and properties of water soluble vitamins? |
Act as coenzymes in metabolic processes. Are dispersed readily in body fluids Excess intake is excreted in urine Marginal deficiencies can develop in ~4weeks of inadequate intake |
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Thiamin |
Vitamin B1. Water-soluble vitamin Sources: Whole grains, beans, pork. Cooking easily destroys this. Functions: Central role in glucose metabolism as it is part of the coenzyme required to convert pyruvate to acetyl CoA for the Krebs cycle. Nervous system function Deficiency: Reduced appetite, confusion, muscle weakness, muscle pain, berberi (severe damage to heart and nervous system). High CHO diets and exercise increase requirements. |
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Functions of Thiamin? |
Central role in glucose metabolism as it is part of the coenzyme required to convert pyruvate to acetyl CoA for the Krebs cycle. Nervous system function |
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Symptoms of deficiency of thiamin? |
Reduced appetite, confusion, muscle weakness, muscle pain, berberi (severe damage to heart and nervous system). High CHO diets and exercise increase requirements. |
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Riboflavin |
Vitamin B2. Water-soluble vitamin. Sources: Dairy, liver, eggs, dark leafy greens, whole grains, enriched cereals Functions: Formation of oxidative enzymes involved in energy production from carbs and fats in cells. Protein metabolism, healthy skin. Deficiency: Can occur in alcoholics. Glossitis (inflammation of the tongue), cracks in corners of mouth, scaly skin around the nose. Supplementation: Requirements may increase in untrained athletes |
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Functions of riboflavin |
Formation of oxidative enzymes involved in energy production from carbs and fats in cells. Protein metabolism, healthy skin. |
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Symptoms of riboflavin deficiency |
Can occur in alcoholics. Glossitis (inflammation of the tongue), cracks in corners of mouth, scaly skin around the nose. |
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Niacin |
Vitamin B3, nicotinic acid, nicotinamide. Water-soluble vitamin Sources: Can be formed in the body using excess tryptophan. Meats, organ meat, fish, poultry, whole grains, cereals, legumes. These are bound to proteins and are hard to be bioavailable unless they are treated. Functions: Components of 2 coenzymes required for energy processes in the cell (one for glycolysis, the other for fat-metabolism) Deficiency: Loss of appetite, skin rashes, confusion, decreased energy, muscle weakness. Can lead to pellagra (dermatitis, diarrhea, dementia) Supplementation: Can cause hepatitis or niacin flush. |
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Functions of niacin |
Components of 2 coenzymes required for energy processes in the cell (one for glycolysis, the other for fat-metabolism) |
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Symptoms of niacin deficiency |
Loss of appetite, skin rashes, confusion, decreased energy, muscle weakness. Can lead to pellagra (dermatitis, diarrhea, dementia) |
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Vitamin B6 |
Also known as pyridoxine. Water-soluble vitamin. Source: Meat, fish, poultry, whole grains, eggs, brown rice. Functions: Coenzyme form is largely involved in protein metabolism (amino acid conversion) and also CHO and fat metabolism. Formation of neurotransmitters, incorporates amino acids into hemoglobin, myoglobin, and oxidative enzymes. Deficiency: Rare. Can be caused by diuretic or oral contraceptive use. Deficiency can cause nausea, decreased immunity, skin disorders, mouth sores, weakness, depression, anemia, seizures. Supplementation: increases with protein intake. No supportive evidence for supplementing in athletes. May reduce PMS symptoms Toxicity: Peripheral nerve damage |
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Functions of vitamin B6 |
Coenzyme form is largely involved in protein metabolism (amino acid conversion) and also CHO and fat metabolism. Formation of neurotransmitters, incorporates amino acids into hemoglobin, myoglobin, and oxidative enzymes. |
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Symptoms of vitamin B6 deficiency |
Rare. Can be caused by diuretic or oral contraceptive use. Deficiency can cause nausea, decreased immunity, skin disorders, mouth sores, weakness, depression, anemia, seizures. |
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Vitamin B12 |
Also known as cobalamin. Water-soluble vitamin Source: Meat, fish, poultry, cheese, eggs, milk. Functions: Part of coenzymes in all cells, required in DNA synthesis in myelin sheaths of nerve fibers, development of red blood cells, metabolism of homocysteine. Deficiency: Common in elderly. Can occur in vegetarians. Caused by a lack of intrinsic factor in GI tract required for absorption. Can lead to pernicious anemia, nerve damage, leading to paralysis. Supplementation: Important for pregnant women, deficient elderly, and vegans. |
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Functions of vitamin B12 |
Part of coenzymes in all cells, required in DNA synthesis in myelin sheaths of nerve fibers, development of red blood cells, metabolism of homocysteine. |
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Symptoms of vitamin B12 deficiency |
Common in elderly. Can occur in vegetarians. Caused by a lack of intrinsic factor in GI tract required for absorption. Can lead to pernicious anemia, nerve damage, leading to paralysis. |
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Folic Acid |
Folate. Water soluble vitamin. Requirements: 400 mcg/day, 600mcg/day in pregnancy Sources: Green leafy vegetables, organ meats, dry beans, whole grains, oranges, bananas, fortified grain products Functions: Part of coenzyme for metabolism of methionine (an essential amino acid). Critical for DNA formation, red blood cell production, and early stages of fetal development Deficiency: Can occur with the use of oral contraceptives or increased alcohol. Can cause anemia, high homocysteine levels (causing neural and vascular issues), increased risk of cancer, and increased risk of neural tube defects. Supplementation: Required in pregnant women. Megadoses can mask vitamin B12 deficiency. Not recommended in athletes unless clinically deficient. |
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Functions of folic acid |
Part of coenzyme for metabolism of methionine (an essential amino acid). Critical for DNA formation, red blood cell production, and early stages of fetal development |
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Symptoms of deficiency of folic acid |
Can occur with the use of oral contraceptives or increased alcohol. Can cause anemia, high homocysteine levels (causing neural and vascular issues), increased risk of cancer, and increased risk of neural tube defects. |
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Pantothenic Acid |
Water soluble. Sources: In most foods, best sources are organ meats, eggs, legumes, and whole grains. Functions: Essential component in coenzyme A (CoA) used in energy metabolism, gluconeogenesis, fatty acid break down, protein modification, and acetylcholine synthesis (for muscle contraction) Deficiency: Fatigue, muscle cramping, impaired motor function |
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Functions of pantothenic acid |
Essential component in coenzyme A (CoA) used in energy metabolism, gluconeogenesis, fatty acid break down, protein modification, and acetylcholine synthesis (for muscle contraction) |
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Symptoms of deficiency of pantothenic acid |
Fatigue, muscle cramping, impaired motor function |
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Biotin |
Vitamin B7. Water soluble vitamin. Sources: Organ meats, egg yolk, legumes, dark leafy veggies. Also produced by bacteria in intestines Function: Coenzyme for amino acid metabolism, synthesis of fatty acids and glucose (gluconeogenesis) Deficiency: A diet high in raw egg whites can cause because they bind to biotin. |
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Functions of biotin |
Coenzyme for amino acid metabolism, synthesis of fatty acids and glucose (gluconeogenesis) |
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Cause of biotin deficiency |
A diet high in raw egg whites can cause because they bind to biotin. |
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Vitamin C |
Also known as ascorbic acid. Water soluble vitamin. Sources: Citrus fruits and green leafy veggies, peppers, potatoes, strawberries, tomatoes. Functions: Modifies mineral ions in enzymes to activate. Important in collagen synthesis (connective tissue), epinephrine formation, iron absorption, RBC synthesis. Regulates folic acid, cholesterol, and amino acid metabolism. Also important in wound healing. Deficiency: Can be caused by smoking, aspirin use, oral contraceptive use, stress. Can lead to scurvy (when skin, tissues, gums, tendons, and cartilage disintegrate causing anemia, impaired wound healing, and muscle cramps) Toxicity: Diarrhea, reduced vitamin B12, decreased copper bioavailability, and gout |
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Functions of Vitamin C |
Modifies mineral ions in enzymes to activate. Important in collagen synthesis (connective tissue), epinephrine formation, iron absorption, RBC synthesis. Regulates folic acid, cholesterol, and amino acid metabolism. Also important in wound healing. |
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Cause and symptoms of vitamin C deficiency |
Can be caused by smoking, aspirin use, oral contraceptive use, stress. Can lead to scurvy (when skin, tissues, gums, tendons, and cartilage disintegrate causing anemia, impaired wound healing, and muscle cramps) |
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Minerals |
Consist of 22 metallic elements. Essential to life. Are not energy producing 7 major minerals (requires amounts >100mg/day) 14 minor minerals/trace minerals (required in amounts <100mg/day) |
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Major Minerals |
7 of them: Calcium, phosphorus, magnesium, potassium, sodium, chloride, and sulfer Required in >100mg/day |
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Trace minerals |
Required in less than 100mg/day Iron, copper, zinc, chromium, selenium |
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Roles of minerals |
Serve as constituents of enzymes, hormones, and vitamins Provide structure information of bones and teeth Synthesize the biologic macronutrients glycogen, fat, and protein. |
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What are the factors that affect mineral bioavailability? |
Type of food Mineral-mineral interaction Vitamin-mineral interaction Fiber-mineral interaction Soil food is grown in Land the food is raised on |
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Calcium |
A macromineral Sources: Milk, cheese, yogurt, ice cream, fish with small bones, dark leafy vegetables, tofu, legumes, nuts Recommended intake: 1000mg/day Milk is the most easiest absorbed in the body because of the vitamin D and lactose content Phytates in legumes and oxalates in spinach can decrease absorption of calcium High protein intake can also lead to calcium excretion Functions: Bone formation, enzyme activation, nerve impulse transmission, muscle contraction, cell membranes Deficiency: Osteoporosis, rickets, impaired muscle movements, cramps Toxicity: Constipation, reduced trace mineral absorption, heart arrhythmia, kidney stones, soft tissue calcification |
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Functions of Calcium |
Bone formation, enzyme activation, nerve impulse transmission, muscle contraction, cell membranes |
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Symptoms of Calcium deficiency |
Osteoporosis, rickets, impaired muscle movements, cramps |
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Symptoms of Calcium toxicity |
Constipation, reduced trace mineral absorption, heart arrhythmia, kidney stones, soft tissue calcification |
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Calcium and osteoporosis |
osteoporosis is bone loss, with bone density more than 2.5 standard deviations below normal age and gender Osteopenia is a midway condition where bones weaken with increased fracture risk Adequate Ca intake and regular weight bearing exercise or resistance training help prevent bone loss at any age |
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Osteopenia |
A midway condition where bones weaken with increased fracture risk |
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Phosphorus |
A macromineral Source: All proteins Function: Bone formation, acid-base balance, cell membrane structure, B-vitamin activation, part of ATP and PCr used in muscle contraction Deficiency: Similar to Ca deficiency, muscle weakness Toxicity: Rare. Impaired Ca metabolism, GI issues, stimulation to release parathyroid hormone. Supplementation: Can interfere with iron and zinc absorption. A 1:1 ratio of Ca to phosphorus is recommended |
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Function of phosphorus |
Bone formation, acid-base balance, cell membrane structure, B-vitamin activation, part of ATP and PCr used in muscle contraction |
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Symptoms of phosphorus deficiency |
Similar to Ca deficiency, muscle weakness |
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Symptoms of phosphorus toxicity |
Rare. Impaired Ca metabolism, GI issues, stimulation to release parathyroid hormone. |
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Magnesium |
A macromineral Sources: Milk, yogurt, dried beans, nuts, whole grains, fruits, veggies, especially green leafy veggies Functions: Protein synthesis, glucose metabolism, smooth muscle contraction, component of bone Deficiency: Muscle weakness, apathy, twitches, muscle cramps, arrhythmia Toxicity: Nausea and vomiting |
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Functions of magnesium |
Protein synthesis, glucose metabolism, smooth muscle contraction, component of bone |
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Symptoms of magnesium deficiency |
Muscle weakness, apathy, twitches, muscle cramps, arrhythmia |
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Symptoms of magnesium toxicity |
Nausea and vomiting |
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Iron |
A trace mineral Sources: Organ meats, meat, fish, poultry, shellfish, oysters, dried beans, whole grains, green leafy veggies, dried fruits, cast iron pans Functions: Hemoglobin and myoglobin formation, electron transfer, oxidation Deficiency: Fatigue, anemia, poor temp regulation, reduced immunity Toxicity: Hemochromatosis, liver damage |
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Iron functions |
Hemoglobin and myoglobin formation, electron transfer, oxidation |
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Symptoms of iron deficiency |
Fatigue, anemia, poor temp regulation, reduced immunity |
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symptoms of iron toxicity |
Hemochromatosis, liver damage |
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Iron and exercise |
Iron is a structural component of myoglobin and the cytochrome Some iron does not combine in functionally active compounds and exists as hemosiderin and ferritin stored in the liver, spleen, and bone marrow. |
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Iron-deficiency anemia |
This condition negatively affects aerobic exercise performance and the ability to perform heavy training |
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Vegetarian diets and anemia |
Non-heme iron (from plant sources) has low bioavailability vegetarian type diets increases risk of deficiency Vitamin C and physical activity increase intestinal absorption of non-heme iron |
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Copper |
A trace mineral Source: Organ meats, meat, nuts, eggs, bran cereals, avocado, broccoli, bananas Function: Proper use of iron and hemoglobin in the body, connective tissue formation, oxidation Deficiency: Anemia Toxicity: nausea, vomiting |
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Functions of copper |
Proper use of iron and hemoglobin in the body, connective tissue formation, oxidation |
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symptoms of copper deficiency |
Anemia |
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symptoms of copper toxicity |
nausea, vomiting |
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Zinc |
A trace mineral Sources: organ meat, meat, dairy, nuts, whole grains, veggies, asparagus, spinach Functions: Cofactor is energy metabolism, protein synthesis, immunity, sexual maturation, taste, and smell Deficiency: Poor immunity, impaired wound healing, reduced appetite, reduced growth, skin inflammation Toxicity: Increased LDL, decreased HDL, reduced immunity, nausea, vomiting, impaired copper absorption |
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What are the functions of zinc? |
Cofactor is energy metabolism, protein synthesis, immunity, sexual maturation, taste, and smell |
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Symptoms of zinc deficiency |
Poor immunity, impaired wound healing, reduced appetite, reduced growth, skin inflammation |
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Symptoms of zinc toxicity |
Increased LDL, decreased HDL, reduced immunity, nausea, vomiting, impaired copper absorption |
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Chromium |
A trace mineral Sources: Organ meats, meats, oysters, cheese, wholegrains, asparagus, beer. Function: Increases insulin fxn as glucose tolerancefactor. Deficiency: Glucose intolerance, impaired lipidmetabolism Toxicity: Rare |
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Functions of Chromium |
Increases insulin fxn as glucose tolerance factor. |
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Symptoms of chromium deficiency |
Glucose intolerance, impaired lipid metabolism |
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Symptoms of chromium toxicity |
Extremely rare. No symptoms to note |
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Selenium |
A trace mineral Sources: Meat, fish, poultry, organ meats, seafood,whole grains, nuts Function: Cofactor for antioxidant enzyme. Deficiency: Cardiac muscle damage Toxicity: Nausea, vomiting, abdominal pain, hair loss. |
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Functions of selenium |
Cofactor for antioxidant enzymes. |
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Symptoms of selenium deficiency |
Cardiac muscle damage |
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Symptoms of selenium toxicity |
Nausea, vomiting, abdominal pain, hair loss. |
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Electrolytes |
Electrically charged particles dissolved in body fluids Ex. Sodium, potassium, chlorine Functions: Establish the proper electrical gradient across cellmembranes. Modulate fluid exchange within the body's fluidcompartments. Regulate the acid and base qualities of body fluids. |
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What are the daily requirements for sodium? |
Recommended is 2400mg. But new research recommends a max of 1500mg. |
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How much sodium is in the average american diet? |
4-4.8 g/day! |
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What are the functions of sodium? |
Main electrolyte in extracellular fluids, maintainsnormal fluid balance (blood volume) and osmotic pressure(blood pressure) |
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Symptoms of sodium deficiency |
Rare, but sodium loss can be caused through prolonged sweating |
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What part of the brain regulates sodium and water balance? |
hypothalamus |
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Aldosterone |
A hormone secreted by the adrenal gland to stimulate the kidneys to retain sodium. |
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Antidiuretic Hormone |
ADH Retains water in the body when necessary. Particularly during exercise |
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What diet can reduce sodium-induced hypertension to the same extent as pharmacological therapies? |
The DASH diet. (Dietary Approaches to Stop Hypertension) |
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Chloride |
A trace mineral Sources: Table salt, most foods. Function: The major negative ion in extracellularfluids, works with sodium to create electrical potentialacross cell membranes, HCl in the stomach. Deficiency: Rare, but can also occur with prolongedsweating. Can affect physical performance. |
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Function of chloride |
The major negative ion in extracellular fluids, works with sodium to create electrical potential across cell membranes, HCl in the stomach. |
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Symptoms of chloride deficiency |
Rare, but can also occur with prolonged sweating. Can affect physical performance. |
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Potassium |
A trace mineral Sources: Most foods, especially bananas, tomatosauces, citrus fruits, vegetables, milk, meat, fish,potatoes Function: A positive ion that works with sodium and chloride to maintain body fluid balance and generate electrical impulses in nerves and muscle, transport of glucose to muscle cells, glycogen storage. Deficiency: Rare, but can occur with fasting, diarrhea,diuretic use. Hypokalemia can lead to muscularweakness and cardiac arrest. Excess: Caused if overdose on potassium supplements. Regulation: aldosterone release from the adrenalcortex causes an increased excretion of potassium fromthe kidneys into the urine. |
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Function of potassium |
A positive ion that works with sodium and chloride to maintain body fluid balance and generate electrical impulses in nerves and muscle, transport of glucose to muscle cells, glycogen storage |
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Symptoms of potassium deficiency |
Rare, but can occur with fasting, diarrhea, diuretic use. Hypokalemia can lead to muscular weakness and cardiac arrest. |
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Regulation of potassium |
Aldosterone release from the adrenal cortex causes an increased excretion of potassium from the kidneys into the urine. |
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Dietary reference intake |
DRI A new and more comprehensive approach to nutritional recommendations for individuals Umbrella term: Encompasses the recommended daily allowance, estimated average requirement, adequate intake, and tolerable upper intake level. |
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Recommended dietary allowance |
RDA The average daily nutrient intake level sufficient to meet the requirement of nearly 97-98% of healthy individuals in a particular life-stage and gender group |
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Estimated Average Requirement |
EAR Averagelevel of daily nutrient intake to meet therequirement of one-half of the healthy individualsin a particular life stage and gender group. |
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Adequate intake |
AI Provides an assumedadequate nutritional goal when no RDA or DRI exists. |
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Tolerable upper intake level |
UL The highest average intake level likely to pose no risk of adverse health effects to almost all individuals in a specified gender and life-stage group. |
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Why do we do nutrition assessments? |
To assess adequacy of macro- and micronutrients in diet To connect diet to health issues To understand how diet can be manipulated to achieve bodycomposition alterations Education/research purposes |
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What is a 3-day food record? |
It is simple and accurate, especially for macronutrients 2 weekdays and 1 weekend day Uses household food measurements (cups, tbsp,...) Includes all foods and beverages Clients need direction on how to properly complete the food record. Disadvantages: Under or over-estimating amounts of food taken in.Typically not detailed enough |
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What is the disadvantages of a 3-day food record? |
Under or over-estimating amounts of food taken in Typically not detailed enough |
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7-day food record |
May be more accurate than a 3-day food record for micronutrients and macronutrients Disadvantage: Poor compliance among participants |
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Duplicate food collections |
Highly accurate nutritional analysis Exact duplicate of portions of participants foods are saved for chemical analysis in the lab. Rarely done because it is expensive Disadvantage: Difficult for the client because they have to make double of their food and store until analysis. |
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Photo food record |
Nutritional assessment where clients take pictures of all food and beverages consumed over a period of time. Can be done in conjunction with food records for verification Lets people become aware of what they are eating |
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24 hour recall |
Common type of nutritional assessment Interviewer must be trained Includes information about timing, preparation of food, the environment Pros: Easy, time-efficient, cost-effective Cons: Underreporting, inaccurate portion recall |
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Food Frequency Questionnaire |
FFQ Nutritional assessment of general intake. Consists of a series of questions. Questions may not include foods regularly in a person's diet. Qualitative Used in research |
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Diet history |
Nutritional assessment that is a mix of the 24-hour recall and the FFQ. Establishes general diet habits and patterns. Provides a better view of overall diet. Requires a skilled interviewer |
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What are the steps for analyzing a diet? |
1) Determine requirements, specific for that athlete 2) Compare food intake to food group recommendations 3) Compare intake to fluid recommendations 4) Compare intake to macronutrients 5) Compare intake to micronutrients 6) Compare diet to recommendations specific to that athlete 7) Big-picture assessment: Are there any patterns you see in the diet? |
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Myofibrils |
The component of muscle that is defined as z-line to z-line that are the boundaries of one sarcomere Has interactions of myosin thick filament and actin thin filament that generates tension in fibre during contraction |
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Myosin Thick filaments |
Myosin is the primary protein. Has a head and a tail. Myosin heads form cross-bridges with actin during contraction Myosin heads have a pocket for the binding and hydrolysis of ATP |
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Actin Thin Filaments |
Primary protein: Actin Attached to a z-disc Each actin molecule has a binding site for myosin heads to initiate contraction. |
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Power stroke |
1) ATP binds to the myosin head 2) Calcium binds to troponin, pulling tropomyosin away from the active sites on actin so myosin heads can bind to actin. 3) ATP is hydrolyzed into ADP + Energy 4) Energy is used in the myosin molecule 5) Myosin binds to actin and releases a phosphate, initiating the power stroke |
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Bioenergetics |
The body's capacity to extract energy from food and transfer it to the contractile elements in skeletal muscle , determining it's capacity to exercise at high intensities |
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Aerobic Reactions |
Require oxygen |
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Anaerobic Reactions |
Don't require oxygen. Typically generate energy rapidly for short durations |
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What is the energy from nutrients utilized for? |
Many things including: - Digestion, absorption, and assimilation of food nutrients - Glandular function that secretes hormones - Maintenance of electrochemical gradients across cell membranes - Synthesis of new chemical compounds and tissues |
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What is the potential energy from food converted into? |
ATP (conserved within the bonds of ATP) By breaking the bonds of 1 ATP molecule, that is freeing 7.3 kcals of energy. |
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What are the different sources of ATP? |
Phosphocreatine Glycolysis Lipolysis Beta-oxidation Oxidative Phosphorylation |
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Phosphocreatine |
Only a small amount of ATP is stored in cells and needs to be resynthesized continually. PCr releases energy when the phosphate is split. Once PCr's are used up, energy must come from stored macronutrients Energy from ATP and PCr only lasts 5-8 seconds |
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How much energy does 1 mole of glucose have? |
689 kcal. Of this ATP bonds conserve ~263kcal and the rest is liberated as heat. |
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Provide a general breakdown of how glucose becomes energy in the body |
1) Glycolysis: Produces a net of 2ATP during anaerobic substrate-level phosphorylation 2) Pyruvate from glycolysis converts to acetyl CoA within the mitochondria 3) Acetyl CoA enters the citric acid cycle/krebs cycle 4) Any hydrogen atoms that have been released this far are oxidized via the electron transport chain |
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How much ATP synthesis takes place at the ETC? |
~90%. |
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How much ATP does the complete oxidation of a glucose molecule in skeletal muscle theoretically yield? |
36 ATP molecules |
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What are the 3 conditions that are necessary for oxidative phosphorylation to continue? |
1) Availability of the reducing agents in the tissues 2) Presence of oxygen in the tissues 3) Sufficient concentration of enzymes and mitochondria in the tissues |
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Formation of lactate |
During intense exercise, when hydrogen oxidation can not keep up with the production (in the ETC), lactate form as pyruvate temporarily binds with hydrogen. Also forms at rest because red blood cells only use anaerobic glycolysis |
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What is the body's most plentiful source of energy? |
Stored fat |
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How many molecules of ATP does the complete breakdown of on triacylglycerol molecule produce? |
~460 molecules of ATP |
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Can fatty acids be synthesized to glucose? |
No, but glycerol can. |
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Fatty acid catabolism requires a lot of...? |
Oxygen. That is why as exercise intensity increases, the more we rely on CHO. |
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What are the sources for fat catabolism? |
- Triglycerides stored in the muscle fibers - Circulating triglycerides in lipoprotein complexes (chylomicrons) - Circulating free fatty acids and glycerol from adipose tissues |
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How many ATP molecules does the breakdown of one glycerol molecule produce? |
19 ATP molecules |
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What does glycerol provide for glucose synthesis? |
Carbon skeletons |
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What process converts a free fatty acid to multiple acetyl-CoA molecules? |
Beta-oxidation |
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Lipogenesis |
The formation of fat, mostly in the cytoplasm of liver cells Excess glucose of protein converts into stored triglycerides (VLDL) Process requires ATP energy and the B-vitamins biotin, niacin, and pantothenic acid |
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How can protein be used as an energy substrate? |
1) Nitrogen is removed from the amino acid molecule via deamination 2) The remaining carbon skeletons enter the metabolic pathways to produce ATP - Some amino acids are ketogenic and some are glucogenic |
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Why is there increased water loss with protein catabolism? |
The amine group and other solutes from protein breakdown must be eliminated. This requires excretion of obligatory water as the waste products of protein catabolism leave the body dissolved in fluid (urine). |
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What catalyze hydrogen's release from nutrient substrates? What accept the electrons from the hydrogen? |
Dehydrogenase coenzymes Nicotinamide adenine dinucleotide (NAD+) and Flavin adenine dinucleotide (FAD) accept pairs of electrons |
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Electron Transport Chain |
Accepts hydrogen molecules released during glycolysis, beta-oxidation, and the krebs cycle. The final common pathway in aerobic metabolism, where oxygen accepts hydrogen and forms water. |
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How are metabolic pathways controlled? |
- Compounds that either inhibit or activate enzymes at keycontrol points in the oxidative pathways modulate control ofglycolysis and the citric acid cycle. - Cellular ADP concentration exerts the greatest effect on therate-limiting enzymes that control energy metabolism.Functions as a cellular feedback mechanism to maintainhomeostasis. - Other metabolic rate-limiting molecules include cellularphosphate levels, cyclic AMP, calcium, NAD+, citrate, andpH. |
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What is energy required for? |
Basic cell and organ function such as: - Ion transport - Protein expression, hormone/peptide secretion - Muscle contraction - Tissue building |
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Anabolism |
Creation. Tissue growth. |
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Catabolism |
Breakdown. Prominent in tissue wasting. |
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How much energy is lost to heat from nutrition conversion to ATP? |
~80% |
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Where is the energy stored in food? |
Its chemical bonds |
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What are the methods to measure energy in food? |
Direct Calorimetry Combustion/Oxidization - Heat produced from these = energy content |
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Power |
Energy expended per unit time |
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How many kilojoules is 1 kcal? |
4.186 kJ |
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1 Joule of energy is required too... |
increase velocity of a mass of 1 g by 1 m/s |
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1 calorie of energy is required too... |
raise the temperature of 1 g of water by 1 degree celcius |
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How much energy (kcal) is contained in 1 molecule of glucose? |
3.75 kcal |
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How much energy (kcal) is contained in 1 molecule of glycogen? |
4.2 kcal |
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How much energy (kcal) is contained in 1 molecule of medium-chain triglycerides? |
8.6 kcal |
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How much energy (kcal) is contained in 1 molecule of long-chain triglycerides? |
9.6 kcal |
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How much energy (kcal) is contained in 1 molecule of protein? |
5.65 kcal |
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How much energy is available in 1 g of CHO? |
4 kcal (Atwater factor) |
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How much energy is available in 1 g of Fat? |
9 kcal (Atwater factor) |
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How much energy is available in 1 g of PRO? |
4 kcal (Atwater factor) |
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How much energy is available in 1 g of alcohol? |
7 kcal (atwater factor) |
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Metabolic Rate |
The measure of how rapidly the body is using energy soucres |
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Total daily energy expenditure |
TDEE Determined by: - Resting energy expenditure - Food intake - Physical activity (not just exercise, but any daily activity, including post-exercise metabolic increase) |
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Methods for estimating energy expenditure |
- Direct Calorimetry - Indirect Calorimetry (respiration chamber, douglas bag...) - Doubly labelled water (expensive and old school) - Heart rate monitoring - Accelerometry |
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Indirect Calorimetry |
Measuring oxygen uptake and carbon dioxide production. Amount of oxygen required to combust food is directly related to energy content (ie. RER) Types: Closed circuit, open-circuit (ie metabolic cart) |
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Resting metabolic rate |
Basal metabolic rate + a small increment due to previous physical activity (about 10% greater) RMR is ~65-70% of TDEE ~1kcal/kg/hr |
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What does metabolic rate depend on? |
Muscle mass (age, gender, fitness, weight loss, low energy diets [hormones], caffeine, smoking, environmental temperature) |
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Dietary induced thermogenesis |
Thermic effect of feeding (TEF) increased temperature due to digestion/absorption of energy following food intake Increase oxygen consumption by 8-10% 1-4 hrs following a meal Magnitude depends on type of food (CHO and PRO >>>Fat) Accounts for ~ 5-10% of TDEE |
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Thermic effect of exercise |
Can vary substantially Typically 15-30% of TDEE (<10% in sedentary or >50% in high performance athletes) Measured as: litres of oxygen (VO2), METS, estimated from heart rate, ventilation, onset of blood lactose accumulation (OBLA), or perceived exertion |
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Low intensity exercise |
Can last for hours Uses both CHO and fat for fuel (RER: 0.82-0.95) Fatigue determined by glycogen depletion, hypoglycemia, and dehydration (loss of minerals) |
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Moderate to heavy intensity |
30-90 min continuous or 5-15 min intermittent More reliance on CHO for fuel (RER: 0.90 - >1.0) Fatigue is due to glycogen depletion (limited body glycogen stores), hypoglycemia, dehydration possible but less likely |
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High/Max intensity |
Lasts a few minutes exclusively CHO Fatigue long before CHO depletion due to acidic environmentin muscle (low pH) Repeated bouts may deplete CHO |
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Supramaximal Intensity |
Lasts for a few seconds fatigue due to PCr depletion (inability to regenerate quicklyenough) and/or muscle acidity |
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What happens when Energy Intake chronically exceeds Energy Expenditure? |
Cause and increase in body mass. Diet composition, exercise regime, and hormonal status affect how increased body mass is manifested (ie muscle vs fat) |
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What happens when Energy Expenditure chronically exceeds Energy Intake? |
Leads to decreased body mass if held consistently for long term (months) In combination with exercise and adequate diet composition, loss of muscle mass is minimized/avoided Not desirable during the competitive season |
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What macronutrients are not easily converted to fat? |
CHO, PRO, and alcohol. Leads to an increase in oxidation of these molecules. |
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Does excess fat intake lead to higher fat oxidation? |
No. It is likely to be stored in adipose tissue. |
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Why do we measure body composition? |
1) Identify physique characteristics of elite performers 2) Monitor effectiveness of training or diet 3) Estimate optimal competition weight/body composition in weight-category sports 4) Screen and monitor athlete's growth, health status to prevent extreme lows in body fat |
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BMI |
Body mass index Compares weight to height May not be accurate for athletes due to muscle mass. Good for general population |
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Waist:Hip Ratio |
When ratio is higher, than there is a higher risk for chronic disease. 20-30yr/olds recommendations: Women: ~0.75 Men: ~0.85 |
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What are the 3 levels of body composition assessment? |
Level 1: Direct (Cadaver analysis) Level 2: Indirect (2 compartment models, FM and FFM) Level 3: Doubly indirect (Regression equations with TOBEC, BIA, Anthropometry, Skinfolds) |
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2 Compartment Body Composition model |
FM & FFM FFM includes bone and water Can be determined with skin folds, hydrodensitometry, air displacement plethsmography, DXA, CT, or MRI |
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3 Compartment Body Composition model |
Total body water, FF dry Mass (FFDM), and FM 2 compartment model AND Deuterium Dilution are used together to determine this. |
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4 Compartment Body Composition model |
Total body water, bone mineral, fat mass, and residual Done by hydrodensitometry (or air displacement), deuterium dilution, and DXA) |
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Is visceral or subcutaneous fat worse? |
Visceral (if in excess). It is closer to the internal organs and can overtake them if in excess. |
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Lipoprotein Lipase |
LPL. Similar to hormone sensitive lipase (HSL) in adipocytes (is sensitive to activation via growth hormone, and epinephrine, which are exercise-stimulated hormones) Positively regulated in response to insulin and CHO in adipose tissue Negatively regulated by insulin in skeletal muscle Catalyzes breakdown of TG to FFA allowing FA into local tissues. Is expressed by endothelial cells of the capillaries. |
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Appetite |
Controlled by the hypothalamus. Hormone that stimulates appetite: Ghrelin Hormones that stimulates satiety: CCK, GLP-1, PYY, Leptin Main hormones: Ghrelin and Leptin All hormones are intertwined with insulin and glucagon secretion |
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Hormone that stimulate appetite |
Ghrelin |
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Hormones that stimulates satiety |
CCK, GLP-1, PYY, Leptin |
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What are the main hormones in appetite control? |
Ghrelin and Leptin |
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Satiety |
The inhibition of eating following a meal,measured by time between meals and amountconsumed at next meal Protein provides higher satiety than CHO and fat (PRO > FAT > CHO) Alcohol reduces inhibition |
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Appetite and Exercise |
High-intensity exercise can reduce appetite initially but notover 2 days Hunger suppressed when: long enough (>60 min), intenseenough (>70% VO2 max) Short- to medium-term exercise resulting in negativeenergy balance does not have effect on intake Long-term: intake will increase to compensate for ~30%of exercise calories |
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What happens when you eat an energy deficient breakfast? |
Increased perceived higher and intake later in the day |
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What factors are important in weight maintenance? |
1. Energy Balance 2. Diet Composition 3. Blood insulin 4. Metabolic Rate |
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Based on *shitty...* research, what is the best diet composition for weight loss? |
High PRO/ low CHO with exercise |
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What are the benefits of eating a high protein diet and exercising? |
Lower insulin -> increasing fat mobilization -> decrease storage Protein sparing effect on lean mass Resistance training maintains or increases lean mass - Lean mass has a high RMR especially during exercise programs - Lean mass increases also helps to increase exercise expenditure of aerobic exercise Increased thermic effect of dietary protein Increased satiety of dietary protein (decreased energy intake) Increased TDEE combined with lower energy intake and greater fat mobilization |
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Why do high CHO diets decrease the activity of skeletal muscle lipoprotein lipase (LPL)? |
Because LPL in skeletal muscle is decreased by the presence of insulin. So your body does not need to burn as much fat for fuel since CHO already exists |
