Exam 1 - Study Guide Flashcards
What Is Exercise Physiology and Why Study It?
Exercise physiology describes and explains responses to exercise and chronic adaptations
What does F.I.T.T. stand for
Frequency, Intensity, Time and Type
how does FIIT influence acute responses and exercise adaptations?
Acute – an adaptation that occurs for one bout vs chronic = over time to exercise bouts
Frequency – Do you exercise enough to adapt? Is it too much that your body wont adapt?
Intensity – maximal or submaximal (quality of overload)
Type – is it continuous, rhythmical/resistance, or strength?
Time – depending on how long the workout bout is for, it can improve aerobic or anaerobic metabolism
List the basic training principles
- Specificity:
- Overload:
- Rest/Recovery/Adaptation:
- Progression:
- Retrogression/plateau/reversibility:
- Maintenance:
- Individualization:
- Warm-Up/Cooldown:
What is specificity
what you do is what you get
What is overload
demand placed on body greater than what it is accustomed/increase the amount of activity required for continued adaptation
What is Rest/Recovery/Adaptation
change in physiological function that occurs in response of training that occurs during periods of rest
What is progression
Change in overload due to a response in adaptation; steploading
What is retrogressoin/plateau/reversibility
retrogression is decrease in performance, plateau = something needs to change (exercise less/more, add variety, add more rest), reversibility = when training stops
What is maintenance
sustaining an achieved adaptation w/most efficient use of time and effort
What is individualization
not a one size fits all – personalized training program
What is warm-up/cool down
prepare body & gradual return to temp
What is stress
Stress is “the state manifested by a specific syndrome that consists of all the nonspecifically induced changes within a biological system”.
List and describe the three stages of Seyle’s theory of stress
Alarm-reaction stage– shock/initial elevation in function: resp, circ, E prod (single bout of ex)
The stage of resistance– the stage of adaptation
The stage of exhaustion – when stress is chronic or adaptation is lost (single bout of ex)
What is the energy value of a 1g of lipid vs. carbohydrate vs. protein
Carbo: 4 kCals E/gram of carbo
Lipid: 9.5 kCals E/gram of fat
protein: 4 kCals E/gram of protein
Know about energy transfer.
- E is transferred to an ATP molecule; can be generated in three ways
- ATP + PCr, Anaerobic (glycolysis), Aerobic (krebs, ETS/OP)
What is a kcal and what does it measure how does this differ from a Joule?
A kcal is the amount of heat required to raise the T of water by 1 degree C. 1 kcal = 4.184 J
What are the first and second laws of thermodynamics?
- Law of conservation of E: E cannot be created or destroyed
- All E goes toward entropy/ disorder
What are entropy, enthalpy and free energy? Delta H = delta G +T(deltaS)
- Entropy (delta S)
- Enthalpy: E available to do work (delta H)
- Free energy (delta G)
What does a calorimeter measure
- Measures the heat liberated or absorbed in metabolic process
What are the differences between a bomb, direct and indirect calorimeter?
Bomb calorimeter: quickly combust to see how much water T increase
Direct: measures actual heat production
Indirect: Spirometry – estimates heat prod by measuring and analyzing expired air for amount O2 consumed and CO2 produced
What is the difference between indirect and direct calorimetry? What is measured by each?
For indirect: O2 expired is directly proportional to aerobic prod of ATP and in calories that is equal to heat produced by the body
Direct: measure heat produced directly in a special chamber
What are the pros and cons of using direct vs. indirect calorimetry?
Direct:
Pro- most accurate measure, Con- Very expensive
Indirect (open-circuit indirect better than closed):
Pro – not expensive
Con – cost of E may be underestimated
How many kCals are released per liter of oxygen consumption for carbohydrates?
(RQ of 1.0): 5.047 kCal/ LO2
How many kCals are released per liter of oxygen consumption for fats?
4.606 kCal/LO2
How many kCals are released per liter of oxygen consumption for proteins?
Between 4.606 and 5.04 kCal/ LO2
What is the reaction that occurs in the phosphagen system? Where does it occur? Does it require O2?
ADP + PCr –> ATP + Cr
It occurs in the cytoplasm in the absence of O2
What is the main enzyme of the phosphagen system?
Creatine kinase
What regulates the rate of ATP synthesis in the phosphagen system?
The amount of PCr available
Define glycolysis
The E pathway responsible for the catabolism of glucose that begins with glucose or glycogen and ends with the product of pyruvate (aerobic) or lactate (anaerobic)
Define glycogenesis
The formation of glucose from sugar
Define glycogenolysis
the process by which stored glycogen is broken down (hydrolyzed) to produce glucose
Define gluconeogenesis
the creation of glucose in the LIVER from noncarbohydrate sources, particularly glycerol, lactate or pyruvate, and alanine
What are the main enzymes of glycolysis and how are they regulated
Hexokinase (glucose –> glycose 6 phosphate): large, irreversible EXERGONIC rxn
PFK (phosphofructokinase) (glucose 6 phosphate –> fructose 1,6 bisphosphate): EXERGONIC RXN that drives thru other endergonic rxns in the process
Pyruvate kinase: forms pyruvate
When is ATP used and generated in glycolysis?
Used steps 1&2
Generated steps 5&8
What are the end products of glycolysis
Pyruvate (lactate if Krebs cycle is slow) and 2 ATP and 2NADH
What is the importance of lactate and the lactate shuttle
lactate is important because it allows the E to leave the cell and move to where it is needed.
What are the potential fates of absorbed glucose in the diet?
Stored as glycogen if there is in excess (through glycogenesis)
Converted to and stored as fat
Into glycolysis to anaerobically yield ATP
Why is maintenance of blood glucose important
Because it is the primary energy source for the brain
How much energy (kcals) is stored as glycogen compared to lipids?
Glycogen stores are relatively small in comparison to fat stores (2 hours heavy exercise glyc vs weeks w/ moderate activity fat)
Normally how much of ATP production in the body comes from amino acids?
Normally there is not much ATP production from amino acids, but it can be done if other stores are low
What is the Felig cycle?
the creation of glucose in the liver from alanine to help regulate and maintain normal blood glucose levels so that the brain, nerves, kidneys, and muscles can draw from the supply
How would you determine how much protein from the diet is being synthesized?
Measure level consumed vs amount lost ie measure nitrogen loss (urine, feces, dead skin cells, etc)
What is the more important fuel at higher intensity exercise? Low intensity?
Higher intensity is carbohydrates and lower is fat
What is the more important fuel at longer duration exercise? Short duration?
longer duration is fat and shorter duration is carbohydrates
What system is relied on for short duration high intensity exercise?
Short duration high intensity relies predominantly on ATP-PC and glycogen stored in muscles
What increases the conversion of pyruvate to acetyl CoA?
increased Ca++ increased [pyruvate] increased insulin low ATP low NADH
What decreases the conversion of pyruvate to acetyl CoA
Decresed Ca++ decreased [pyruvate] decreased insulin High ATP High NADH
What are the potential fates of acetyl CoA?
Enter the Krebs cycle
Be converted into a FA
What is the rate limiting enzyme of Krebs cycle?
Isocitrate dehydrogenase (ICD)
What is Isocitrate dehydrogenase stimulated by
Low Energy state - high ADP, low ATP, low [NADH]
List the regulatory enzymes of the TCA
Isocitrate dehydrogenase
Citrate synthase
Alpha-ketoglutarate dehydrogenase
What is the ATP yield of the complete oxidation of glucose?
36 ATP
How does [citrate] influence TCA cycle?
if high [citrate], less acetyl-CoA will enter and whole cycle will slow down
What is the chemiosmotic theory?
E is produced by ions following their gradient across the membrane allowing for the proton carriers to transfer H+ across the mem
What happens to the ETC without O2?
No ATP can be produced bc O2 is the final electron receptor
What drives ATP synthase?
Motive force of movement of H+ and e- across the mitochondrial membrane
Fate of lipids?
TAG can be cleaved by hormone sensitive lipase (HSL)
Lipolysis and beta-ox L breakdown of lipids to FA and glycogen
Fate of proteins?
aa to… Acetyl CoA to go into Krebs cycle and reversed or pyruvic acid and reversed
Fate of carbohydrates?
go into glycolysis to produce ATP
Potential to become lipid
What relationship exists between intensity and the energy system being utilized?
Short duration high intensity relies predominantly on ATP-PC and glycogen stored in muscles
What system would predominate for maximal effort lasting 5 seconds, 2 minutes, 30 minutes?
5 SEC: ATP-PCr-
2 min: anaerobic metabolism ie ATP-PC and LA
30 min: O2/aerobic system
What is the lactate threshold
break in linear rate of blood lactate that produces a large increase
Process of lactate accumulation at high exercise intensities
Fast-twitch glycolytic muscle fibers recruited which produce lactic acid when they contract no matter if there is sufficient O2 or not.
LDH isoenzyme 4 & 5 facilitate this conversion of pyruvate to lactate
What is VO2
VO2 is the volume of oxygen consumed during a bout of exercise
What happens to VO2 at a constant workload?
< 70% VO2 max, remain constant (steady state)
>70% VO2 max, start to increase (O2 drift)
What is EPOC? What occurs during EPOC?
Excess post-exercise O2 consumption: the amount of extra O2 consumed following a bout of exercise
This is the time in which body T lowers, PCr stores replenished, HR lowers back to normal, and some clearance of lactate
If oxygen consumption does not initially meet demands, then how is a workload maintained during the initial stages of exercise?
Anaerobic ATP PCr system is used initially
What is the half life of lactate following exercise
It is 15-20 minutes post exercise
What are the causes of EPOC?
Restoration of ATP-PC stores
Restoration of O2 stores
Elevated cardiovascular – respiratory function (more breaths and higher HR)
Elevated hormonal levels (epine and nore)
Elevated body T (most important of EPOC – Increase T = Increase in metaboic rate)
Lactate removal – accum of lactate must be removed
E substrate shift (from carbo to fat during this recovery)
What is the Hill-Meyerhoff theory
States that during recovery, a fair amount lactate is oxidized and we still have lactate consumption as long as O2 is present – a portion getting resyn as glycogen as well
What is RQ?
the ratio of CO2 produced/CO2 consumed at the cellular level
What is the difference between RQ and RER?
RQ is cellular whereas RER is the whole body resp and is usually below 0.7 (dip in CO2 following exercise bout) or above 1.0 (excess CO2)
What is the normal RQ for fat? For Carbohydrates?
Fat: 0.7
Carbohydrate: 1.0
Can RQ go above 1.0 or below 0.7?
It goes above 1.0 when there is a high deposition of fat from carbohydrates
What happens to VO2 in short, light/moderate intensity exercise?
It increases and then levels off
What happens to VO2 in long, moderate/heavy intensity exercise?
Increases, levels off, then increase again due to cardiac drift
What happens to VO2 in incremental exercise to max intensity exercise?
It will keep increasing until you reach VO2 max (theoretical) or VO2 peak (actual)
What is the equation for work?
W = force (load) x distance (rev/min *d)
Equation to calculate the caloric cost of an activity
Caloric cost of an activity (kcal/min) = O2 consumed (L/min) * caloric equivalent (kcal/LO2)
Equation for Efficiency
Efficiency = work output/E expended *100
How many kg work = 1 kcal
426.8 kg
What are the factors that influence economy of movement
Sex – if O2 cost is equal at a speed, females will be working at a higher VO2 max than males
Age - children/adolescents are less economical than adults; older adults – economy is higher than child but lower than adult
Training – the more trained, the better the economy
Can someone’s Vo2 be different at the same external workload?
Yes - it depends on the efficiency of the movement
