Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
332 Cards in this Set
- Front
- Back
|
what two dietary components have the greatest effect on raising blood cholesterol levels?
|
saturated and trans fats
|
|
|
True or false: to maximize glycogen stores, athletes should eat CHO within 30 minutes after exhaustic endurance exercise.
|
True
|
|
|
True or false: to enhance muscle protein synthesis and muscle repair, athletes should include protein in their post-workout meal.
|
True
|
|
|
A food label that states 98% fat-free indicates that the food contains only 2% fat as a percentage of calories or weight?
|
weight
|
|
|
these are substances necessary for life that build and repair body cells, and maintain structural and functional integrity of the organism
|
nutrients
|
|
|
what are the four macronutrients in the body?
|
(1) CHO
(2) fat (3) protein (4) water |
|
|
what are the two micronutrients in the body?
|
vitamins and minerals
|
|
|
this is the sum of all the chemical and physical processes involved in producing energy, synthesizing and degrading structural and functional tissue components, and disposing of resultant waste products
|
metabolism
|
|
|
what are the three processes that make up metabolism?
|
(1) producing energy from exogenous and endogenous sources
(2) synthesizing and degrading structural and functional tissue components (3) disposing of resultant waste products |
|
|
this is the movement of glucose into cells
|
glucose transport
|
|
|
this is the breakdown of glucose
|
glycolysis
|
|
|
this is glycogen synthesis
|
glucogenesis
|
|
|
what enzyme catalyzes glycogen synthesis (glucogenesis)?
|
glycogen synthase
|
|
|
this is the breakdown of glycogen
|
glycogenolysis
|
|
|
this is the creation of new glucose (synthesis)
|
gluconeogenesis
|
|
|
How many kcals do you get from 1 gram of CHO?
|
4 kcal
|
|
|
how many kJ do you get from 1 gram of CHO?
|
17 kJ
|
|
|
this is a simple sugar that is made up of one carbohydrate
|
monosaccharide
|
|
|
what are three types of monosaccharides?
|
(1) glucose
(2) fructose (3) galactose |
|
|
these are simple sugars that are made up of two carbohydrates
|
disaccharides
|
|
|
these are complex sugars that are made up of many carbohydrates
|
polysaccharides
|
|
|
what are three types of disaccharides
|
(1) sucrose (glucose and fructose)
(2) lactose (glucose and galactose) (3) maltose (glucose and glucose) |
|
|
what are three types of polysaccharides?
|
(1) starch (plant)
(2) fiber (plant) (3) glycogen (animal) |
|
|
can disaccharides be absorbed by the digestive system?
|
no
|
|
|
what are some sources of soluble fiber in the diet?
|
oatmeal, beans, peas, carrots, and fruit
|
|
|
what are some sources of insoluble fiber in the diet?
|
whole grains
|
|
|
this type of fiber binds to LDL and decreases it
|
soluble fiber
|
|
|
this type of fiber promotes digestive health
|
insoluble fiber
|
|
|
what are six health benefits of eating fiber?
|
(1) decreased obesity
(2) decreased type 2 diabetes (3) decreased digestive disorders (4) decreased cholesterol (5) decreased heart disease (6) increased satiety |
|
|
what food is the highest in total fiber and insoluble fiber?
|
bran cereal
|
|
|
what two foods are the highest in soluble fiber?
|
apples and potatoes
|
|
|
CHO is stored as what substance in the muscle and liver?
|
glycogen
|
|
|
what is glucose in skeletal muscle cells called?
|
muscle glycogen
|
|
|
what is glucose in liver cells called?
|
liver glycogen
|
|
|
excess carbohydrate contributes to what stores in the body?
|
adipose tissue
|
|
|
how many kcals of energy are stored in the body as CHO
|
1500-2000 kcals
|
|
|
where is the most CHO stored in the body?
|
muscle
|
|
|
the body's stores of CHO are enough to power a __ mile run at high intensity
|
20 mile
|
|
|
what is the upper limit for glycogen storage in the body?
|
15 g/kg of body mass
|
|
|
what are the four roles of CHO in the body?
|
(1) energy source (excess-->adipose tissue)
(2) protein sparer (3) metabolic primer (enables fatty acid oxidation) (4) fuel for CNS (brain predominantly uses glucose) |
|
|
this substance is secreted when blood glucose is high, causing energy storage (anabolic process)
|
insulin
|
|
|
this substance is secreted when blood glucose is low, causing glycogenolysis, and gluconeogenesis (catabolic process)
|
glucagon
|
|
|
the secretion of glucagon in the body in response to low blood sugar triggers what two processes?
|
glycogenolysis
gluconeogenesis |
|
|
the mixture of fuel utilized during exercise depends on what four things?
|
(1) intensity of exercise (increased intensity-increased CHO)
(2) duration of exercise (3) fitness level (4) nutritional status |
|
|
does protein have an anabolic or catabolic role in the body?
|
anabolic (builds new tissue)
|
|
|
what is a macronutrient that is vital for life, growth, and structural support of body cells?
|
protein
|
|
|
about 65% of the body's total protein is located where?
|
skeletal muscle
|
|
|
protein in the body is comprised of what substances linked together?
|
amino acids
|
|
|
what four elements comprise amino acids?
|
(1) carbon
(2) hydrogen (3) oxygen (4) nitrogen |
|
|
how many different types of amino acids are there?
|
20
|
|
|
which type of fat has a double bond, which gives it fluidity?
|
unsaturated
|
|
|
this type of fat is solid at room temperature, has no double bonds, and increases LDL and cholesterol
|
saturated fat
|
|
|
what are animal sources of saturated fat?
|
buter, lard, and fatty meats
|
|
|
what are plant sources of saturated fat?
|
coconut, palm oil, and palm kernerl oil
|
|
|
this type of fat is liquid at room temperature and has either a favorable or neutral effect on plasma cholesterol
|
unsaturated
|
|
|
this type of unsaturated fat has 1 carbon-carbon double bond and can be found in olive oil, canola oil, nuts, olives, and avocado
|
monounsaturated fat
|
|
|
this type of unsaturated fat as two or more carbon-carbon double bonds and can be found in oils such as corn, soybean, sunflower, and canola, and fish
|
polyunsaturated fats
|
|
|
there is a high correlated between intake of trans fatty acids and what disease?
|
heart disease
|
|
|
what are some sources of omega-3 fatty acids?
|
fish, fish oil, flaxseed and flaxseed oil, canola oil, and walnuts
|
|
|
what are the three health benefits of omega-3 fatty acids?
|
decreased risk for heart disease, blood clots, and arrhythmias
|
|
|
this is a fat-like substance present in the body and in foods; it is a necessary component of the body needed for normal hormonal functioning, but is not necessary in the diet because our bodies can synthesize it
|
cholesterol
|
|
|
these two substances reduce cholsterol absorption in the gut and enhances cholsterol secretion (which can favorable impact blood cholesterol levels)
|
plant sterols and stanols
|
|
|
what are the natural sources of plant phytosterols?
|
wheat germ (whole grains)
|
|
|
how many kcals can you get from 1 g of lipids?
|
9 kcals
|
|
|
what is the average dietary intake of lipids?
|
25-160 g/day as triacylglycerols
|
|
|
what foods are highest in essential fatty acids?
|
vegetable oils
|
|
|
what are the four fat soluble vitamins?
|
A, D, E, and K
|
|
|
what are the four functions of dietary lipids?
|
(1) source of energy
(2) source of essential fatty acids (3) vitamin carrier for fat-soluble vitamins (4) hunger depressor (provides satiety and takes longer to metabolize) |
|
|
what are the five functions of fat storage?
|
(1) energy storage
(2) vitamin storage (3) protection of organs (4) insulation (5) hormonal functions |
|
|
this is the breakdown of lipids (triacylglycerol catabolism)
|
lipolysis
|
|
|
lipolysis is catalyzed by what enzyme?
|
hormone-sensitive lipase
|
|
|
what four conditions does lipolysis occur under?
|
(1) low to moderate intensity exercise
(2) prolonged exercise that depletes glycogen stores (3) calorie restriction/fasting (4) cold stress |
|
|
what is the ratio for RQ?
|
CO2 produced/O2 consumed
|
|
|
what is the RQ/RER when someone is burning pure CHO?
|
1.00
|
|
|
what is the RQ/RER when someone is burning predominantly fat?
|
.7
|
|
|
does free fatty acid mobilization increase or decrease with longer duration exercise?
|
increase
|
|
|
does respiratory quotient (RER) increase or decrease with longer duration exercise?
|
decrease (greater reliance on fat for fuel)
|
|
|
water makes up what percentage of body mass?
|
40-60%
|
|
|
water is associated predominantly with fat or lean body mass?
|
lean
|
|
|
what are the four functions of water in the body?
|
(1) carry food and oxygen
(2) carry wate products out of the body (3) give structure and form to the body (4) temperature and regulation |
|
|
rehydration after prolonged exercise in the heat with plain water may result in what condition?
|
hyponatremia
|
|
|
what are the conditions for hyponatremia in the body?
|
serum sodium less than 136 mEq/L
|
|
|
thirst is stimulated when body water decreases what percentage?
|
1.7-3.5%
|
|
|
performance is impaired in the body when fluid losses are greater than what percentage?
|
2%
|
|
|
a medical consultation is needed for someone in relation to water in what two conditions?
|
(1) weight loss of greater than 4% (dehydration)
(2) weight gain of any amount (too many fluids) |
|
|
what are the two water soluble vitamins?
|
B and C
|
|
|
what are the seven major minerals in the body?
|
(1) calcium
(2) phosphorus (3) potassium (4) sulfur (5) sodium (6) chlorine (7) magnesium |
|
|
what are the seven trace minerals in the body
|
(1) iron
(2) fluoride (3) zinc (4) copper (5) selenium (6) iodine (7) chromium |
|
|
what level determines if a mineral is trace or major in the body?
|
if greater than or less than 100 mg/day is required in the body)
|
|
|
this is the most abundant mineral in the body
|
calcium
|
|
|
with phosphorus, calcium represents about --% of the body's mineral content
|
75%
|
|
|
what provides a stimulus to maintain/increase bone mass during exercise?
|
mechanical loading of bone
|
|
|
what vitamin plays an important role in bone health?
|
vitamin D
|
|
|
a precompetition meal maximizes muscle and liver -- stores
|
glycogen
|
|
|
a precompetition meal should include how many grams of CHO? When should it take place before the event?
|
150-300 g CHO, 2-4 hours before event
|
|
|
to minimize GI distress before a competition, what two substances should be as little as possible in the precompetition meal?
|
fat and fiber
|
|
|
this is the quantity of heat needed to raise the temperature of 1 L of water by 1º C
|
calorie
|
|
|
this is the standard SI unit for food energy
|
Joule
|
|
|
1 kcal contians how many kJ?
|
4.184 kJ
|
|
|
this is a direct measurement of the energy value of foods; assessed by the heat liberated during complete oxidation of nutrients
|
bomb calorimetry
|
|
|
what is the percentage diet recommendation of total calories for CHO?
|
45-65% of total kcals
|
|
|
what is the percentage diet recommendation of total calories for fat?
|
20-35% of total kcals
|
|
|
what is the percentage diet recommendation of total calories for protein?
|
10-35% of total kcals
|
|
|
how many times per week at least should you eat fish, especially oily fish?
|
twice
|
|
|
you should limit your intake of saturated fat daily to less than -% of energy
|
7%
|
|
|
you should limit your intake of trans fat daily to less than -% of energy
|
1%
|
|
|
you should limit your intake of cholesterol daily to less than - mg per day
|
300 mg
|
|
|
what are four recommendations from the american cancer society to maintain a healthy lifestyle?
|
(1) maintain a health weight throughout life
(2) adopt a physically active lifestyle (3) eat a healthy diet, with emphasis on plant sources (4) if you drink alcohol, do so in moderation |
|
|
what are four ways to assess energy intake in the diet?
|
(1) food diaries
(2) 24 hour recall (3) food frequency questionnaires (4) doubly labeled water |
|
|
this is the universal energy currency for all endergonic and exergonic reactions in the body; principal immediate donor of free energy in biological systems
|
adenosine triphosphate (ATP)
|
|
|
when food energy is used to resynthesize ATP, how many kcals are used per mole of ATP hydrolyzed?
|
7.3 kcals/mole
|
|
|
when food energy is used to resynthesize creatine phosphate, how many kcals are used per mole of PCr hydrolyzed?
|
10.3 kcals/mole
|
|
|
there is a very limited quantity of ATP stored in the body, amounting to __ grams, which is only enough to power the body for 3-6 seconds
|
85
|
|
|
creatine phosphate (PCr) is stored where in the body?
|
sarcomere of skeletal muscle cells
|
|
|
creatine kinase is stored at what part of the skeletal muscle cell?
|
MLine of the sarcomere
|
|
|
the ATP-PCr system is enough to power the body in all-out exercise for how long?
|
30 seconds
|
|
|
what enzyme catalyzes the breakdown of creatine phosphate to creatine, inorganic phosphate, and energy?
|
creatine kinase
|
|
|
what are two possible side effects of creatine phosphate supplementation?
|
(1) weight gain (water weight)
(2) lots of nitrogen (not good for patients with kidney disease because they have to work harder to eliminate) |
|
|
what is the maximum rate of ATP synthesis in skeletal muscle from PCr?
|
150 mmol ATP/min/kg muscle
|
|
|
what is the maximum rate of ATP synthesis in skeletal muscle from glycolysis?
|
84 mmol of ATP/min/kg
|
|
|
what is the maximum rate of ATP synthesis in skeletal muscle from pyruvate oxidation?
|
36 mmol of ATP/min/kg
|
|
|
what is the maximum rate of ATP synthesis in skeletal muxcle from free fatty acid oxidation?
|
15 mmol of ATP/min/kg
|
|
|
what are three factors that influence the rate of energy transfer in the body?
|
(1) law of mass action (direct relationship between concentration of chemicals and frequency of chemical reactions)
(2) enzymes (3) coenzymes |
|
|
these are highly specific protein catalysts that act to accelerate the speed of a chemical reaction
|
enzymes
|
|
|
these are complex, non protein organic substances that facilitate enzyme actions by helping bind the substrate with its specific enzyme; less specific and aid many diverse reactions
|
coenzymes/cofactors
|
|
|
what are five mechanisms of regulating metabolic processes/pathways?
|
(1) rates of enzymatic synthesis/degradation/catalytic rates
(2) reversible allosteric control (inhibited or stimulated by ultimate product of pathway or reaction (3) covalent modification of enzyme altering chemical nature/structure (4) biosynthesis/degradative pathways (5) energy charge-status of cell, ATP need dictates pathways used |
|
|
what is a universal molecule that all macronutrients funnel down to?
|
Acetyl CoA
|
|
|
what is the role of oxygen in aerobic metabolism?
|
final electron acceptor in ETC
|
|
|
what is the only macronutrient in the body which can directly generate energy anaerobically without oxygen?
|
CHO
|
|
|
What are the two stages of glucose oxidation?
|
(1) anaerobic glycolysis
(2) aerobic glycolysis |
|
|
what are the two fates of glucose in the cell?
|
(1) use it
(2) store it |
|
|
too much ATP inhibits what enzyme during glycolysis?
|
phosphofructokinase (PFK)
|
|
|
what does ADP do to glycolysis and PFK enzyme?
|
upregulates it
|
|
|
this is the 10 step metabolic process for the rapid production of 2 ATPs
|
glycolysis
|
|
|
what enzyme during glycolysis splits ATP to ADP, making glucose 6 phosphate?
|
hexokinase
|
|
|
this anaerobic process is the oxidation of 1 glucose into 2 3 carbon molecules of pyruvate
|
glycolysis
|
|
|
how many pyruvate molecules are derived from one glucose molecule?
|
2
|
|
|
what is the rate limiting enzyme of anaerobic glycolysis?
|
phosphofructokinase (PFK)
|
|
|
what is the yield of hydrogen from glycolysis?
|
2 H (in the form of NADH)
|
|
|
in the cytosol, how many ATP are NADH worth?
|
2 ATP for each NADH molecule
|
|
|
formation of this molecule serves as temporary storage for excess hydrogens so NAD+ can accept more ydrogens to keep ATP resynthesis going
|
lactic acid (lactate)
|
|
|
what are three sports that are glycolytic activities?
|
(1) Hockey
(2) football (3) track (400 m) |
|
|
where is the highest concentration of lactate dehydrogenase seen?
|
skeletal muscles (especially fast twitch glycolytic muscles)
|
|
|
what enzyme catalyzes the conversion of pyruvate into lactic acid?
|
lactate dehydrogenase
|
|
|
what is the normal resting blood lactate level?
|
1 mmol
|
|
|
what is the general recovery time to get blood lactate back down to resting levels after vigorous exercise?
|
about 10 minutes
|
|
|
this threshold is reached when there is exceeded capacity for aerobic pathways, and the person is now realying on anaerobic pathways and making more of this substance
|
lactate threshold
|
|
|
what are four factors that are related to lactate threshold?
|
(1) low tissue oxygen
(2) reliance on glycolysis (3) activation of fast-twitch muscle fibers (4) reduced lactate removal |
|
|
what is a typical untrained person's lactate threshold?
|
4 mmol (50-55%)
|
|
|
this cycle shuttles lactate into the blood and takes it to the liver for gluconeogenesis (also used by kidneys, brain, and heart)
|
Cori Cycle
|
|
|
what organelle is known as the "powerhouse" of the cell?
|
mitochondria
|
|
|
what organelle is the major energy producing site and major site of aerobic metabolism in the cell?
|
mitochondria
|
|
|
what organelle in the cell contains many of the major enzymes of long-term energy system and aerobic metabolism?
|
mitochondria
|
|
|
what is the rate limiting enzyme of the Krebs cycle?
|
citrate synthase
|
|
|
what is a cofactor that contains pairs of electrons that comes out of the Krebs cycle?
|
FADH2
|
|
|
what is the second stage of oxidizing glucose?
|
aerobic glycolysis
|
|
|
this process generates the necessary pairs of electron for synthesizing ATP
|
aerobic glycolysis
|
|
|
how many ATP are given for each NADH in the mitochondria?
|
3 ATP
|
|
|
how many ATP are given for each FADH2 in the mitochondria?
|
2 ATP
|
|
|
what is the site of oxidative phosphorylation in the electron transport chain?
|
mitochondria
|
|
|
where in the mitochondria does the electron transport chain take place?
|
inner mitochondrial membrane
|
|
|
what is the rate limiting enzyme of the electron transport chain?
|
cytochrome oxidase
|
|
|
what enzyme in the electron transport chain transfers the electrons to molecular oxygen?
|
cytochrome oxidase
|
|
|
the complete aerobic oxidation of 1 glucose molecule results in how many ATP synthesized?
|
36
|
|
|
what are three requirements for continual re-synthesis of ATP?
|
(1) adequate supply of O2
(2) adequate supply of substrates (e.g. hydrogens in the form of NADH+, H+ and FADH2) (3) ETC enzymes (e.g. cytochrome oxidase) |
|
|
how do you measure the levels of cytochrome oxidase that someone has?
|
muscle biopsy
|
|
|
for each turn of the Krebs cycle, what are four products that are produced, and how many ATP does that produce?
|
(1) 3 NADH + H+
(2) 1 FADH2 (3) 1GTP (ATP) (4) 4 CO2 (8 hydrogens) This all yields 12 ATP |
|
|
the energy yield of the aerobic system is -- times the yield of anaerobic glycolysis
|
18
|
|
|
the longterm aerobic energy system takes how long to fully activate?
|
3-5 minutes
|
|
|
the energy yield from the longterm (aerobic) energy system is about --% of the glucose molecule
|
95%
|
|
|
where does the longterm (aerobic) energy system occur?
|
mitochondria
|
|
|
the ratios of what two substances in the cytoplasm in the mitochondria signal the demand for energy?
|
ATP/ADP and NADH/NAD+
|
|
|
what two substances in the mitochondria are enzyme inhibitors for aerobic metabolism?
|
ATP and NADH
|
|
|
what two substances in the mitochondria are enzyme activators for aerobic metabolism?
|
ADP and NAD+
|
|
|
what are the five steps in lipid metabolism and free fatty acid oxidation?
|
(1) lipid mobilization
(2) circulation (transport from adipose to skeletal muscle) (3) uptake of free fatty acids into skeletal muscle (4) activation (formation of Acetyl CoA) (5) translocation (long chain Acetyl CoA transported by a carrier) |
|
|
what is the normal range of percent body fat in a 25 year old male?
|
15-18%
|
|
|
what is the normal range of percent body fat in a 25 year old female?
|
22-25%
|
|
|
when free fatty acids ar e being transported from adipose tissue to skeletal muscle, what is a common plasma protein that is used to transport it?
|
albumin
|
|
|
how many ATP does it cost to form Acyl CoA during lipid metabolism?
|
1 ATP
|
|
|
where does the formation of Acyl CoA occur during lipid metabolism?
|
outer mitochondrial membrane
|
|
|
what is a carrier than transports long chain AcylCoA into the intermuscular membrane during lipid oxidation?
|
carnitine
|
|
|
this is the sequential breakdown of long-chain acyl-CoA's into acetyl CoA (2 carbon fragments) where NADH and FADH2 are generated
|
beta-oxidation
|
|
|
what are the 4 steps required during beta oxidation of acylCoA into acetylCoA?
|
(1) oxidation
(2) hydration (3) oxidation (4) thiolysis |
|
|
in mitochondrial oxidative phosphorylation, what enzyme drives the reaction of triglyceride breakdown into a glycerol and three fatty acids?
|
lipase
|
|
|
what are the four substances that can cause a mobilization of triglycerides?
|
(1) epinephrine
(2) norepinephrine (3) insulin (4) caffeine |
|
|
what substance inhibits lipolysis and promotes more lipid storage?
|
insulin
|
|
|
what substance stimulates lipolysis and promotes more lipid breakdown?
|
glucagon (and also exercise)
|
|
|
in order to metabolize fat, you must have an adequate supply of what substance?
|
oxygen
|
|
|
long chain fatty acids must be carired into the mitochondria by a carrier protein; what protein is most often used?
|
carnitine
|
|
|
how many ATP does it cost to "activate" the free fatty acid chain?
|
1 ATP
|
|
|
this is the oxidation of the beta-carbon fatty acid
|
beta oxidation
|
|
|
for each turn of the beta oxidation cycle, what are the things that are produced?
|
(1) 1 FADH2
(2) 1 NADH + H+ (3) 1 Acetyl CoA -3 NADH+ H+ -1 FADH2 -1 GTP (get these last three from the Krebs cycle) |
|
|
what are two criteria that need to be met in order for fat oxidation to proceed?
|
(1) O2 must be available to accept hydrogens
(2) a basal amount of CHO oxidation must be present to replace carbon skeletons of Krebs cycle intermediates |
|
|
incomplete lipid breakdown results in the accumulation of what by-products, which can lead to acidosis?
|
ketone bodies (acetoacetate, hydroxybutarate)
|
|
|
in what disease process is it important to check for ketones in the blood and urine?
|
diabetes
|
|
|
oxaloacetate is synthesized from pyruvate under the control of what enzyme?
|
pyruvate carboxylase
|
|
|
carbohydrates are often interconverted to what two macronutrients?
|
lipids or nonessential amino acids
|
|
|
lipids are often interconverted to what macronutrient?
|
nonessential amino acids
|
|
|
proteins are often interconverted to what two macronutrients?
|
carbohydrates or lipids
|
|
|
what substance in the body provides the stimulus to get amino acids into cells?
|
insulin
|
|
|
to use amino acids as a fuel for the body, what substance do you need to dispose of?
|
nitrogen
|
|
|
these are the amino acids that cannot be synthesized in the body
|
essential amino acids
|
|
|
these proteins contain all the essential amino acids
|
complete proteins
|
|
|
these proteins lack one or more of the essential amino acids
|
incomplete
|
|
|
what are the three major sources of body protein?
|
(1) blood plasma
(2) visceral tissue (3) muscle |
|
|
what are the major building blocks for synthesizing tissue (from protein)?
|
amino acids
|
|
|
the disposal of nitrogen from protein metabolism is reflected int he plasma production of what substance?
|
NH4+
|
|
|
what four substances do proteins contain?
|
(1) carbon
(2) hydrogen (3) oxygen (4) nitrogen |
|
|
what are the three components of an amino acid?
|
(1) amine group
(2) organic acid group (3) R group or side chain |
|
|
what are five sources of complete proteins?
|
(1) eggs
(2) milk (3) meat (4) fish (5) poultry |
|
|
what is the recommended dietary protein intake range for infants and growing children?
|
2.0-4.0 g/kg/day
|
|
|
amino acids that are not used in protein metabolism structurally undergo what process?
|
deamination
|
|
|
during deamination of amino acids not used in protein metabolism, what is the nitrogen removed to form?
|
urea
|
|
|
the remnant of amino acids that are not used in protein metabolism that have been deaminated can go on to do what three things?
|
(1) converted to a different amino acid
(2) converted to a carbohydrate or fat (3) catabolized for energy |
|
|
this occurs when nitrogen intake equals nitrogen excretion
|
nitrogen balance
|
|
|
what does a positive nitrogen value indicate?
|
new tissue being synthesized (anabolic state)
|
|
|
what does a negative nitrogen value indicate?
|
protein is being used for energy and possible encroachment on amino acids (catabolic state)
|
|
|
where does deamination of amino acids occur?
|
liver
|
|
|
what are the preferred oxidation fuel by muscle in protein metabolism?
|
branch chain amino acids
|
|
|
this type of amino acid in protein metabolism that enters at the level of acetyl CoA or the Krebs cycle
|
ketogenic
|
|
|
this type of amino acid in protein metabolism that enters tat the level of pyruvate and yields more energy
|
glucogenic
|
|
|
when there is an increase in ammonia production from protein metabolism, there is a subsequent increase in what cycle by the liver?
|
urea cycle
|
|
|
what is a good marker of protein oxidation in the body?
|
ammonia in urine
|
|
|
what is the major site of amino acid degradation?
|
liver
|
|
|
protein is oxidized more extensively in the body as what energy store becomes depleted?
|
carbohydrates
|
|
|
what are the three major gluconeogenic precursors?
|
(1) lactate
(2) glycerol (3) amino acids (especially alanine) |
|
|
what are the three components of total energy expenditure?
|
(1) physical activity
(2) thermic effect of food (3) resting metabolic rate |
|
|
this is the metabolic cost of living ; energy that is required for metabolic activities
|
basal metabolic rate
|
|
|
what are five metabolic activities that require energy at rest?
|
(1) cellular functions
(2) blood circulation (3) respiration (4) GI function (5) renal function |
|
|
what percentage range of total energy expenditure does the basal/resting metabolic rate make up?
|
60-75%
|
|
|
what are six conditions that need to be met in order to measure someone's true BASAL metabolic rate?
|
(1) awake, but motionless
(2) supine (3) no talking (4) fast 10-12 hours before (5) No exercise before test (usually required to be inpatient) (6) thermoneutral room |
|
|
what is the most variable component of total energy expenditure?
|
thermic affect of physical activity
|
|
|
what percentage range of total energy expenditure does the thermic effect of food make up?
|
15-30% (maybe up to 60% for athletes)
|
|
|
this is a measure of exercise intensity relative to resting metabolic rate
|
metabolic equivalent (MET)
|
|
|
how much is 1 MET equivalent to?
|
3.5 mL/kg/min
|
|
|
how do you compute someone's physical activity level (ratio of what to what)?
|
Total energy expenditure/resting metabolic rate
|
|
|
what are four possible ways to assess someone's energy expenditure?
|
(1) activity monitoring devices (pedometers, heart rate monitor)
(2) direct caloriemeters (heat) (3) indirect calorimeters (4) Doubly labeled water |
|
|
what is the most accurate way to assess "free living" energy expenditure of a person?
|
doubly labeled water
|
|
|
this type of indirect calorimetry is measured when someone rebreathes O2 from a spirometer, and CO2 is removed as expired air and is filtered over sode lime
|
closed-circuit spirometry
|
|
|
this type of indirect calorimetry is when someone is inhaline room air (more open air flow), allowing them to quantify volume and concentration of air
|
open-circuit spirometry
|
|
|
what are 10 factors that affect energy expenditure at rest?
|
(1) body mass
(2) lean body mass (muscle) (3) body surface area (4) age (5) sleep (6) recent physical activity (7) temperature (8) pregnancy (9) post-surgery (10) burn victims |
|
|
what are 6 factors that affect energy expenditure during exercise?
|
(1) body mass (esp. during WB exercise)
(2) intensity and duration (3) temperature (4) type of exercise (5) individual's fitness level (6) skill |
|
|
what are 7 influential factors that can affect estimating VO2 and energy expenditure from heart rate?
|
(1) environmental temperature
(2) emotions (3) previous food intake (4) body position (5) muscle groups involved (6) static vs. dynamic contractions (7) continuity of exercise |
|
|
below how many METS is the relationship between HR and estimated VO2 max not so great?
|
3 METS
|
|
|
what are the four possible factors to consider in the female athlete "tetrad"?
|
(1) disordered eating
(2) amenorrhea/other menstural irregularities (3) osteoporosis (4) cardiovascular risk? (based on decreased vasodilation endothelial function test-seen in patients with heart failure) |
|
|
this is the maximal attainable rate of oxygen consumption where O2 uptake rate plateaus and shows no further increase, despite further increases in workload
|
VO2 max
|
|
|
does VO2 max give information on anaerobic or aerobic energy systems?
|
aerobic
|
|
|
this is the best expression of an individual's physiological capacity to transport and utilize oxygen; best measure of cardiorespiratory fitness and long term energy system
|
VO2 max
|
|
|
which VO2 max measure is measured in relation to body weight?
|
relative
|
|
|
the majority of the adaptation to increase VO2 max is mostly in what system?
|
cardiovascular system
|
|
|
What is the Fick equation that allows you to compute VO2 max?
|
VO2 max=Q x a-vO2 difference
|
|
|
to increase the a-v O2 difference in the body, what should you increase density of?
|
mitochondria
|
|
|
what is the max a-v O2 difference that has been noted in world class athletes?
|
20 ml O2 per 100 ml of blood
|
|
|
tremendous increases in VO2 max can be accomplished by what three things?
|
(1) increase in cardiac output
(2) increase in stroke volume (3) increase in extraction of O2 in working skeletal muscle |
|
|
what are the five criteria for attaining a "true" VO2 max?
|
(1) plateau in O2 uptake rate despite increase in workload
(2) within +/- 10 beats of age-predicted maximal heart rate (3) RER greater than 1.10 (4) Blood lactate levels of 8 mmol/L or greater (5) Maximal rating of perceived exertion (RPE) score of 18-20 |
|
|
lactate peaks in blood within about how many minutes of intense exercise?
|
10
|
|
|
what does a level of 8 mmol or greater of lactic acid during a VO2 max test tell us?
|
we have exceeded aerobic capacity and are using anaerobic capacity
|
|
|
this is obtained when a VO2 max value is not able to be obtained, and represents the highest value of O2 uptake rate measured during the exercise test
|
VO2 peak
|
|
|
what is the normal resting heart rate?
|
70 bpm
|
|
|
does the heart rate max increase or decrease with age?
|
decreases
|
|
|
a decrease in HR has an associated __ in stroke volume/cardiac output to meet energy demands
|
increase
|
|
|
the more muscle mass that is activated during a test (increases/decreases) VO2 max
|
increases
|
|
|
what VO2 max values (absolute or relative) decrease for females due to a rapid weight gain?
|
relative
|
|
|
the lactate threshold is about --% in the untrained individual
|
50%
|
|
|
what are seven factors that affect VO2 max?
|
(1) mode of exercise
(2) heredity (3) state of physical training (4) body size (5) body composition (6) gender (7) age |
|
|
genotype determines between -- and --% of VO2 max
|
10 and 30%
|
|
|
women have -- to --% lower VO2 max values than men of similar age and body stature
|
15-30%
|
|
|
exercise training can increase VO2 max values -- to --% depending on the training and initial fitness level
|
5-50%
|
|
|
detraining occurs -- times as rapidly as training-induced adaptations (lose it faster than you gain it)
|
2 times
|
|
|
what are the two major factors for why men have better VO2 maxes than women?
|
(1) body composition ( women have more fat mass)
(2) Hemoglobin (men have a 10-14% higher content) |
|
|
there is a decline in VO2 max at a rate of about --% per year after age 25
|
1%
|
|
|
continuous endurance exercise training can attenuate the age-related decline of VO2 max so that it only declines at a rate of about --% per year
|
0.5 %
|
|
|
is it better to have VO2 max alone, or to know both the VO2 max and the lactate threshold?
|
know both, so you know when you switch to anaerobic systems
|
|
|
incremental workload stages during a VO2 max test usually last about -- to -- minutes
|
2-3 minutes
|
|
|
what type of relationship exists between VO2 and exercise intensity?
|
linear
|
|
|
what type of relationship exists between VO2 max and heart rate?
|
linear
|
|
|
what are four ways to obtain heart rate measures?
|
(1) ECG/EKG
(2) palpation of peripheral pulses (3) pulse rate monitor (4) Stethoscopes, doppler analyzers, etc. |
|
|
what are five things that affect heart rate?
|
(1) emotional stress/anxiety (hormones)
(2) over-training or prior physically activity (resting heart rate lower in those that are more trained) (3) inadequate sleep (4) medications/drugs (5) Day to day variation (usually about 5 bpm) |
|
|
this test to estimate VO2 max is when someone walks as steay and fast for 1 mile, measure time, record HR immediatley after
|
Rockport walk test
|
|
|
what is the target population for the Rockport walk test to estimate VO2 max?
|
males and females with low fitness level (suitable for all ages, very young to very old)
|
|
|
what are two disadvantages of using a heart rate monitor?
|
(1) prediction error may be large (greater than 10%)
(2) Submaximal exercise assumptions may not be met (cannot be used for anaerobic tasks) |
|
|
what are three disadvantages to the Rockport walk test?
|
(1) test is too easy for highly fit individuals
(2) must walk as fast as possible (3) Accuracy depends on your pacing ability and level of motivation |
|
|
this test that estimates VO2 max is based on the linear relationship between VO2 and running speed; the person runs/jogs as hard as they can within 12 minutes and you measure the exact time and distance covered-pace should be steady!!
|
cooper 12 minute run test
|
|
|
what is the most popular field test used to estimate VO2 max?
|
3 minute step test
|
|
|
how many inches high is the step used in the 3 minute step test?
|
16 inches
|
|
|
what is the step rate for women for the 3 minute step test?
|
22 steps per minute
|
|
|
what is the step rate for men for the 3 minute step test?
|
24 steps per minute
|
|
|
what are the typical units that energy is expressed in?
|
kilocalories or kilojoules
|
|
|
what are the typical units that work is expressed in?
|
kg*m or ft*lb
|
|
|
what are the typical units that power is expressed in?
|
watts or kg*m/min, ft*lb/min
|
|
|
a respiratory quotient (RER) of .90 implies that the individual is metabolizing what percentages of fat and carbohydrates?
|
33% fat and 67% carbs
|
|
|
what does a respiratory quotient (RER) of greater than 1.00 signify?
|
excess CO2 production relative to O2 consumption
|
|
|
this is the production of glucose from other nutrients, such as amino acids, lactate, and glycerol
|
gluconeogenesis
|
|
|
what is the largest source of stored energy in the body?
|
adipose tissue
|
|
|
what is the role of oxygen in metabolism?
|
act as the final electron acceptor in the electron transport chain
|
|
|
what is the only substrate that can be used to generate ATP anaerobically?
|
CHO
|
|
|
what is the rate-limiting enzyme in the anaerobic glycolytic pathway?
|
phosphofructokinase (PFK)
|
|
|
what are four things that can cause glycogen depletion in the body?
|
(1) diabetes
(2) consecutive days of heavy exercise training (3) a long exercise bout at moderate to high intensity (4) ketogenic diets (high fat, low carb) |
|
|
the anaerobic breakdown of 1 mole of glucose produces a net of how many pyruvate and how many ATP molecules?
|
2 pyruvate and 2 ATP
|
|
|
what does direct calorimetry measure?
|
heat production
|
|
|
what does indirect calorimetry measure?
|
oxygen consumption
|
|
|
what are the three factors that predict aerobic performance?
|
(1) VO2 max sets the upper limit of aerobic performance
(2) lactate threshold (3) running economy |
|
|
this is the least amount of energy expenditure at a given walking/running speed
|
running economy
|
|
|
untrained lactate thresholds are usually __-__% of VO2 max
|
50-60%
|
|
|
endurance trained lactate thresholds are usually __-__% of VO2 max
|
70-90%
|
|
|
lactate threshold can be enhanced by what type of training?
|
interval
|
|
|
at lactate threshold, what energy system is predominating?
|
anaerobic
|
|
|
at speeds of about __ km/hr or __ mph, it becomes more economical to jog/run than to walk briskly, and it becomes difficult to predict O2 uptake around this pace
|
8 km/hr or 5 mph
|
|
|
this is the lowest oxygen uptake at a given speed of movement while performing a task (e.g. walking or running), and is a trainable concept
|
economy of movement
|
|
|
this is the ratio of the amount of energy required to perform a particular task to the actual work accomplished (in a sense, the wasted energy of performing the same task)
|
gross mechanical efficiency (actual work accomplished/input of energyx100)
|
|
|
wha tis the largest factor in inefficiency of metabolism?
|
heat
|
|
|
the gross mechanical efficiency of human locomotion in walking, running, and cycling is usually __-__%
|
20-30%
|
|
|
this is the lack of oxygen utilization at the start of exercise; expressed in relative or absolute VO2 until steady rate is achieved; can also be considered the oxygen utilization that is required to get to steady state
|
oxygen deficit
|
|
|
this is the difference between the total oxygen actually consumed during exercise and the total oxygen that would have been consumed had an immediate steady state of aerobic metabolism been reached
|
oxygen deficit
|
|
|
for endurance trained athletes, steady state is achieved (slower, quicker), and therefore they have a (smaller, larger) oxygen deficit
|
quicker, smaller
|
|
|
the fact that endurance trained athletes achieve steady state quicker is largely a function of what adaptation?
|
cellular adaptations in skeletal muscles (e.g. mitochondrial enzymes, myoglobin, more and larger mitochondria, increase in hexokinase and PFK)
|
|
|
does creatine supplementation reduce the oxygen deficit and dramatically improve the transitions to steady rate aerobic metabolism and performance?
|
Yes, it can help enlarge the pool of ATP PCr
|
|
|
what is the important thing to be cautious of when someone is taking creatine supplementation?
|
be cautious of high N load (esp. for people with kidney disease)
|
|
|
this is the excess oxygen uptake above the resting energy expenditure which occurs after exercise has stopped
|
oxygen debt
|
|
|
what are the two portions of oxygen debt?
|
(1) fast component (50% decrease in O2 uptake every 30 sec until RMR achieved)
(2) slow component (mins to hours, depending on intensity and duration) |
|
|
both components of oxygen debt may be reduced with chronic exercise training of what type?
|
endurance
|
|
|
which is larger, oxygen deficit or debt?
|
debt (therefore, energy for recovery is greater than energy used at the beginning)
|
|
|
this is the total amount of oxygen consumed after exercise in all organs UNTIL returning to resting energy expenditure, and is not JUST based on the lactic acid level
|
excess post exercise consumption
|
|
|
what are six things that cause the excess post-exercise oxygen consumption?
|
(1) resynthesis of ATP and CP in skeletal muscles
(2) resynthesis of lactate to glycogen (cori cycle in liver) (3) oxidize lactate for energy in metabolism (4) thermogenic effects of elevated core body temperature (5) thermogenic effects of hormones (6) effects of elevated metabolism on organs |
|
|
the onset of blood lactate accumulation in the body indicates that what system is taking place?
|
glycolysis
|
|
|
what are resting levels of lactate in the blood?
|
< 1 mmoL/L
|
|
|
what other threshold during exercise corresponds closely to lactate threshold?
|
ventilatory threshold
|
|
|
recovery HR is __ proportional to VO2 max for untrained persons, but is faster for trained persons
|
inversely
|
|
|
at exercise intensities <__% VO2 max, there is usually little lactate and very quick recovery; passive recovery is sufficient
|
50%
|
|
|
at exercise intensities >/= to __%, active aerobic recovery is faster (helps to mobilize lactate back to the liver)
|
60%
|
|
|
between 30-45% of VO2 max, the optimum recovery is doing what activity?
|
cycling
|
|
|
between 50-60% of VO2 max, the optimum recovery is doing what activity?
|
running
|
