glucose - blood sugar; comes from digestion in liver(mono)

fructose - sugar in fruits; converted to glucose in the liver(mono)

galactose - combined with glucose to make milk sugar in mammary gland(mono)

sucrose - glucose+fructose; 25% of caloric intake for average american; table sugar (di)

lactose - glucose+galactose; milk sugar only; lactose intolerant= lack "lactase" enzyme (di)

maltose - glucose+glucose; smallest part of diet -- cereal, beer (di)

2 forms of polysaccharides - starch and fiber

starch - storage of CHO in plants; complex carbs; 50% of carb intake; grains, potatoes, corn; amylose+amylopectin

fiber - mostly make up structural components in plans; can't digest!

exercise intensity on muscle fuel source - - high intensity = more carb

- low intensity = more fat

Carbohydrate fuel - 1. blood glucose from liver

2. muscle glycogen

Fat Fuel - 1. plasma free fatty acids (adipose tissue)

2. intramuscular triacylglycerols (IMTG)

Muscle fuel - 1. Muscle glycogen

2. intramuscular triacylglycerols

Blood-borne fuel - 1. plasma free fatty acids (adipose tissue)

2. blood glucose

low intensity vs. high intensity specific fuel sources - -low intensity: lacks muscle glycogen as fuel source so PLASMA FATTY ACIDS

-high intensity: MUSCLE GLYCOGEN!

Can muscle glycogen be transported? - NO! cannot be transported from one muscle to another

Glycogen - - storage of CHO in animals

- long link of glucose molecules

- stored in liver and muscle

- liver glycogen -> blood glucose

- muscle glycogen-> local store of fuel for contraction

glycogen breakdown - 1.glycogenolysis - glycogen -> glucose for fuel

2. glycogen is major source for high intensity

3. hit the wall when run out

muscle glycogen is key for performance - endurance!

CHO DISTRIBUTION: - 1. plasma glucose (16 kcal)

2. liver glycogen (400 kcal)

3. muscle glycogen (1600 kcal)

what is the norm blood glucose level before exercise? - 5 mM -- continues to decrease with exercise

order of energy source during exercise: - 1. muscle glycogen

2. IMTG

3. blood glucose

4. plasma fatty acids

gluconeogensis occurs more than glycogenolysis during exercise. (T or F) - FALSE! break down of glycogen in liver happens way more than generation of glucose from other sources

higher intensities of exercise lead to more glycogenolysis - true

gluconeogenesis - - happens in liver

- lactate can leave muscle and go to liver to be converted to glucose

liver produces 2 times as much glucose in intense exercise vs. rest (T OR F) - TRUE!

does glucose uptake increase or decrease with increase exercise intensity - increase!

ROLE OF CHO IN BODY - - brain uses almost only glucose for fuel

- primary fuel for muscles during exercise

- difficult to maintain intensity with depleted sugar levels

LIPIDS - - 3 kinds: simple, complex, and derived

- dietary fat = triglycerides

- same elements as carbs but linked differently

lipolysis - -triglyceride broken down to release fatty acids for energy

lipase - enzyme needed to break down triglycerides by adding H20

Fatty acids - -chain of C with H attached

- # of C and H determines properties

- saturated and unsaturated

Saturated fatty acids - -NO double bonds: H attached to every possible binding site

- mostly in animal fat,dairy, eggs,

-SOLID @ room temp

Unsaturated fatty acids - -1 or more double bonds

-MONOunsat: 1 double bond: olive, peanut oils

-POLYunsat: more than 1 double: sunflower, corn, safflower oils

-hydrogenation: ADD H!(remove double bonds) makes spreads -- more unhealthy

-LIQUID @room temp

compound lipids - lipids + other molecules

- phospholipids (lipid and phosphate)--> essential component of cell membrane

- glycolipids (lipid and carbo) --> antibody identification

-lipoproteins (lipid and protein)--> makes lipid water soluble; major form of lipid transport in blood

lipoprotein types - -chylomicrons : packaged triglycerides from diet

-high density lipoproteins (HDL) : good cholesterol

-low density lipoproteins (LDL):bad cholesterol

-very low density lipoproteins (VLDL): mostly triglyceride inside; food goes to liver and cholesterol and tricylglycerol combine to make VLDL (makes more cholesterol if too low)

- NORMAL CHOLESTEROL =200 mg/dl

ADIPOCYTES AND LIPIDS/FA ARE NOT THE SAME THING!!! - true

DISTRIBUTION OF FAT STORAGE - 1. adipose tissue = 108,000 kcal

2. intramuscular tricylglycerols = 2,700 kcal

3. plasma tricylglycerols = 36 kcal

4. plasma FFA =3.6 kcal

is there more lipid or carb storage in muscles? - more kcal of LIPID bc only 2,000 total kcal of glycogen

lipid use during exercise - 1. fat is PRIMARY FUEL at REST/ LOW INTENSITY

2. proportion of energy from fat decreases as exercise intensity increases -- but either way fat use is still very high!!!

contribution of plasma fatty acids and IMTG - - increase intensity = half and half

- decreased intensity = mostly plasma fatty acids

PROTEINS - - examples are hormones, enzymes, transporters, hemoglobin

- metabolism -> protein is constantly "turning over"

---- tissue building= anabolism

---- tissue breakdown=catabolism

what is different between amino acids? - R group!

what is the r group for alanine? - CH3! can also be converted to glucose (pyruvate first) and used in gluconeogensis

what is deamination - nitrogen removed from amino acids; occurs in liver and forms urea

what is transamination - when N2 is removed from one amino acid and passed to another to pass energy

Nitrogen Balance - N intake = N excretion; negative balance = malnourished; positive balance = growth, children, pregnant women

what is the recommended protein intake - 0.8 g/kg of body weight (50-100 g of protein per day)

what kind of issues can excess protein lead to? - kidney and liver problems

Lipid soluble vitamins - ADEK!

- stored, slow turn over (daily ingestion not necessary)

- low fat diet may lead to deficiency

- toxic if have too much

water soluble vitamins - B and C's

- not stored (fast turn over)

- lots are lost in urine

-potency:8-14 hours

-need more frequently

Minerals - -can join with compounds to make proteins (iron in hemoglobin -- need it bc binding site)

Major minerals contribution!

Calcium

sodium

Mg - Ca- muscle contraction, bone formation

Na- nerve function, water and acid/base balance

Mg- protein synthesis

(when in doubt- acid base balance)

Water!

-% of body mass?

-% of muscle mass?

% of Fat mass? - -BM: 40-70%

-MM: 65-75%

-FM: 10%

functions of body water - - lubricates tissues

- transport medium

- cushions and protects

-temperature regulation

transient hypoglycemia - - eating breakfast leads to increased blood glucose, so increased insulin, so increased glucose uptake; so with workout--> more glucose uptake which may lead to crash, but probably not

glycemic index -- high vs. low - value that represents how high a given meal increases blood glucose concentration

- high GI--> immediately released into blood stream --> increased insulin response

- decrease in glucose does not cause fatigue, often unnoticed

relationship of lipolysis and insulin - lipolysis is very SENSITIVE to insulin -- insulin enhances glucose into fat cells

Glycemic index and lipolysis -- - -lipolysis is REDUCED MORE after high glycemic meals than low glycemic meals

PRE-EXERCISE MEAL SUMMARY: - - meals more than 4 hours before exercise leads to INCREASED GLYCOGEN

- meals less than an hour before exercise leads to DECREASED glucose in early exercise for short time and decreased lipolysis after CHO meal

CHO INGESTION DURING EXERCISE -- why does it delay fatigue? - - prevents hypoglycemia

- increase CHO oxidation late in exercise bc can't rely only on fat stores

- DOES NOT spare muscle glycogen to save for later use

recommendations for CHO ingestion during exercise - 30-60 g CHO/hr

Gastric emptying -- what increases or decreases rate? - -increases rate:

-- increased volume

-decreases rate:

-- increase in caloric content

-- increase in solute concentration (osmolality)

-- exercise intensity >75% VO2 max

-- deviations from 7 pH

-- dehydration

fluid absorption -- what affects it - ALL INCREASE INTESTINAL FLUID ABSORPTION:

-low to mod level of glucose and sodium

- hypotonic to isotonic fluids with NaCl and glucose

adequate fluid replacement -- how much CHO needed in drink? - 4%

CHO after exercise - GOAL -- increase muscle glycogen

-highest rate of glycogen synthesis occurs after exercise -- so eat high cho after working out

recommendations for CHO after workout - 500-600 g CHO

what is hyponatremia and who is more likely to get it? - - low sodium in blood; people who are above and below optimal BMI are more likely to have this

components of daily energy expenditure and percentages - - RMR (60-75%)

-DIT (10%)

- physical activity (15-30%)

BMR what is it and how to find it - - sit for 30 min before measuring

-estimates number of calories needed to function

-RMR is less strictly measured than BMR

how much can rigorous exercise increase energy expenditure compared to resting? - 10 times!

physical activity ratio (PAR) - - light work = 3x resting (EE)

- heavy work=6-8x resting

-maximal = >9x resting

metabolic equivalents (MET) - multiple of RMR

- 1 met=3.6 ml/kg/min

-2 mets= 2 rmr

- way to measure energy expenditure not at rest

calorie - quantity of heat necessary to raise the temp of 1 ml of water by 1degree c

-300 calories on food wrapper is really 300 kcal and 300,000 calories

bioenergetics - -converting food to energy

-all forms of energy are interchangeable

-energy transfer occurs by releasing energy trapped in chemical bonds

energy need for bodily work (types of work and examples) - mechanical work - muscle contraction

chemical work-protein synthesis

cell transport work - pump ion across membranes

Who would benefit from a drug that increase ATPase? - -high endurance athletes! may be detrimental bc rigor mortis bc ATPase breaks down the ATP

ATP breakdown reaction - ATP --> ADP + P + energy

what are the cells 2 major energy transforming activities? - 1. take potential energy in food and store in bonds of ATP

2. break down ATP to use energy for biological work

ATP supply - -small quantity so need to continually resynthesizes

- extreme exercise conditions lead to levels in skeletal muscle to decrease

-stores only 80-100 g of ATP while resting

Phosphocreatine (PcR) - energy for ATP resynthesis from anaerobic splitting of phosphate from PCR

-CELLS STORE ABOUT 4-6 TIMES MORE PCR THAN ATP!!!

glycolysis energy investment and generation - investment : 2 ATP

generation: produces ATP, NADH, pyruvate and/or lactate

energy release from macronutrients - Stage 1: digests/absorbs macronutrients

Stage 2: degrades all into acetyl-CoA

Stage 3: acetyl CoA degrades into H20 and CO2 to make ATP

energy release from CHO - -complete oxidation of glucose molecule yields 30-32 ATP

-LOTS of energy from breaking down glucose dissipates as heat

glycolysis: two forms of CHO breakdown - -aerobic: pyruvate is end product-- SLOW process

-anaerobic: lactate formation -- RAPID process

lactic acid stays in same muscle(T orF) - FALSE! lactic acid spreads to all muscles and can be measured anywhere

when does pyruvate convert to lactate? - 2 molecules of pyruvate from anaerobic breakdown of glycolysis. lactate forms when NADH oxidation doesn't keep pace with formation in glycolysis

-- aka during exercise, not enough O2 so pyruvate takes H+ from NADH and forms lactate and NAD+ to allow glycolysis to continue

energy metabolism regulation (enzyme inhibitors and activators) - INHIBITORS: ATP and NADH

ACTIVATORS: ADP and NAD+

what has the greatest effect on rate limiting enzymes that control macronutrient energy metabolism? - cellular ADP concentration!

lipogenesis - formation of FAT when glucose and protein aren't used for energy

fats require intermediates generated in carb breakdown for their continual catabolism for energy - true

what breakdown provides more power? (fat or carb) - carb breakdown!! so depleting muscle glycogen decreases a muscles max aerobic power output

Acetyl CoA - -common point where rules meet at start of ATP production

-glucose>pyruvate>acetyl coA

-fatty acid>fatty acetyl coA>acetyl coA

-protein>AA> acetyl CoA

what are products of krebs cycle and what is it for? - completes oxidation of substrates for oxidative phosphorylation; produces 3 NADH and 1 FADH

cellular oxidation - mitochondria remove electrons from hydrogen and eventually pass them to O2

electron transport chain - - final pathway where electrons from Hydrogen are passed to O2

-mitochondrial O2 is driving source of change bc final acceptor to combine with hydrogen to form water

-provides 95% of all cellular energy

oxidative phosphorylation - synthesizes ATP by transferring electrons from NADH and FADH2 to O2

-more than 90% of ATP synthesis takes place in respiratory chain

-reducing agents (NADH AND FADH) donate electrons to form gradient

- 2.5 ATP for every NADH and 1.5 ATP for every FADH

hypothesis for ATP formation - electron transport chain results in pumping H+ions through inner membrane space to inter membrane space--> creates gradient so that H+ diffuses back to cytosol where ADP and P can then combine to form ATP(through ATP synthase)

efficiency of oxidative phosphorylation (GREAT EFFICIENCY! - yields 32 ATP from 1 mol of glucose

-34% efficiency of aerobic respiration --66% energy released as heat!!!! -- more over weight people would benefit from reduced efficiency

ATP at rest and during exercise - 500:1 ATP:ADP ration -- with exercise.. ratio gets much smaller but overall ATP DOES NOT CHANGE MUCH!

can all forms of energy transfer occur at once during exercise? - YES!!! just may not play a big role

ATP-PC immediate energy - limited storage of high energy phosphates

ratio of PCR to ATP at rest: 5:1

nuclear resonance imaging(NMR) - used to measure number of high energy phosphates

glycolysis for short term energy - -forms ATP rapidly, but exhausts quicker

- 2 ATP/mol of glucose

Lactate threshold - - low tissue O2 --> reliance on glycolysis --> activation of fast twitch muscle fibers--> reduced lactate removal

blood lactate potential uses - - lactate shuttle -- converted to pyruvate and oxidized as energy in diff cell

-gluconeogenesis -- converted back to glucose in liver in cori cycle

cori cycle - conversions of glucose to lactate from muscle to liver

O2 consumption with exercise - O2in-O2out =O2 consumption

-O2 MEASURED at lung not tissues but O2 USED in tissues NOT LUNG

steady state - when O2 demand is met by O2 delivery

- no lactate accumulation

VO2 and exercise intensity - -as VO2 increases, EE increases

- VO2 max - point where VO2 no longer increases with increasing intensity

oxygen deficit - - transition from rest to exercise -- takes time for O2 to reach steady state

- difference between total O2 consumed during exercise and total O2 that would have been consumed if VO2 reached steady state immediately

oxygen debt - -measured O2 in recovery - theo resting O2 concentration

- pay back for metabolic alterations to get body back to pre-exercise condition

-larger recovery with increased intensity

-most lactate is oxidized for energy **

EPOC (excess postexercise O2 consumption) - may be due to ventilation, hormones, circulation, temp, reloading blood with O2

direct vs indirect calorimetry - -direct: subject enclose din container and measures heat production

-indirect: uses measurements of VO2 to asses energy expenditure -- Vexpired LESS THAN Vinspired l VO2= o2 inspired-o2 expired

Respiratory quotient (same as respiratory exchange ration -RER) - -shows substrate utilization

- RQ range =.7-1.0

-CARB: 1.00 ; all fat = 0.70

-combination of use =.85

RER > 1 ..how? - happens at HIGH INTENSITY

-- happens bc excess of CO2 to compensate for lactic acid accumulation--> SO CO2 is not from substrate but is from acid base balance

doubley labeled water technique - - goal is to calculate O2 consumption over time to estimate energy expenditure (days)

- can calculate from CO2 production

DIT! - 1)obligatory thermogenesis : energy needed to digest food

2) facultative thermogenesis : related to increased activation of sympathetic nervous system which can lead to an increase in energy metabolism

NON-exercise activity thermogenesis (NEAT) - -spontaneous activity (fidget, twitch, pacing)

-lean individuals are usually more fidgety

-increased neat--> decreased fat gain

what climates increase BMR - cold and hot! cold more

THE BIGGEST LOSER! -- what was it measuring? and how? - - wanted to see if this program helped preserve fat free mass and maintain resting metabolic rate

-RMR went down but fat loss was mostly not lean mass

-measured TDEE and measured RMR by indirect calorimetry

lipolysis and glucose relationship - increased glucose in blood --> increased insulin --> lipolysis DECREASES because doesn't want to break back down after just bringing it from the blood