KINE 321 - exam 2
During intense aerobic exercise, how can the digestive organs, liver and kidney tolerate
Lesser amount of blood, you can still recieve the same amount of O2 from a lesser amount of blood
What are the Respiratory Zones?
(17-23) comprimised of bronchiolws, alveolar ducts and alveoli (site of gas exchange) - surfactant production (in the alveolar endothelium) - molecule activation and inactivation (in capillary endothelium) - blood clotting regulation - endocrine function
Define - angina pectoris - thrombus - myocardial infarction
- angina pectoris: chest pain - thrombus: blockage - myocardial infartion: heart attack (heart muscel death)
What are elastic arteries? What function do they serve?
- any large artery that can strech and recoil - maintain blood pressure while heart is in rest
What are the major differences in structure between an artery, vein, and capillary? How do these structures help carry out their specific fuctions?
- artery have thick walls and are more structured - veins are thinner and more flexible - capillaries are super thin and small
What hormones are particularly helpful to an asthmatic if released during exercise? What type of exercise helps release this hormone?
- catecholamines - swimming
List four important factors that influence person's TDEE. Which has the most profound effect?
- physical activity* - diet-induced thermogenesis - calorigenic effect of food on exercise metabolism - climate - pregnancy
What are the three physiological mechanisms outlined in your text by which SV increases during exercise?
- the first, intrinsic to the myocardium, involves enhanced cardiac filling in diastole followed by a more forceful systolic contraction - Neurohormonal influence governs the second mechanism that involves normal ventricular filling with a subsequent forcefl injection and emptying during systole - Training adaptations that expand blood volume and reduce resistance n blood flow in peripheral tissues provides the third mechanism
What physically detemines air pressure? What is normal atmopheric pressure and what does this value (and unit of measurement) mean?
- the ressure that air molecules raise the level of mercury in a barometer - at sea level it is a 760 mmHg or 1 torr
What is the Frank-Starling law of the heart? What is the physical mechanism by which it works? How does body posistion affect the mechanism?
- theory on the relationship between conractile force and the resting length of heart muscle fibers - "within physiological limits, the force of contractionis directly proportional to the inital length of the muscle fiber" - upright to recumbent position (horisontal gives stronger values) *more you fill = more you stretch= more optimal length of muscle stretch = more power for next beat *drops when you lay down because heart fills with more blood
What is orthoptopic transplantation? What is the physiological reason for the complications with exercise response in pateints folllowing the transplantation?
- transplantation of the heart - empphasizes the importance of extrinsic neural control of exercise in the heart - removing and replacing protions of the heart
What would cardiac out be for an untrained college -aged males while exercising at maximal oxygen consumption? How would these values change for a world class endurance athlete?
- untrained: 22,000 mL/min - trained:35,000 mL/min
What are venules? What are the larges veins?
- venules are small veins - largest vein is the infereior vena cava
What factors contribute to total drag force?
- wave drag - skin friction drag - viscous pressure drag
WHat three common methods assess cardiac output in humans?
-Direct Fick - Indicator dilution - CO2 rebreathing
What two reasons listed in the text account for a lower cardiac output at the same level of VO2 with a trained indvidual?
1. more effective distribution 2. enhanced ability of that muscle to generate ATP from O2 (better at using it)
At what age does the difference in VO2 max appear between genders?
12-16 yrs
At about what % of total vital capacity does alveolar ventilation begin to increase with breathing frequency?
60%
According to one specific study by Morgan and Craig (1992), what % of total variation in 10 km running performance among athletes can be explained by the variations in running economy?
64%
According to the text, what 4 variables influence lung volumes? Which variable exhibits the greatest influence on lung volumes?
??
For the average male, a VO2 of 750 mL O2/min is egual to how many METS?
??
How would you respond to a question from a friend related to the best way to modify breathing to increase VO2 max and performance in a 10K?
??
If a person runs 5 miles in one hour and another person of the same mass runs 5 miles in 30 mins, who burns more calories?
??
Provide three secondary criteria which objectify VO2 peak
??
What is autorhythmicity? WHat is the pacemaker? How does it work?
??
When is physiologic dead space considered to be substantial?
??
What one factor can make a cycling test difficult for a non-cyclist?
?? - dont have the ability to perform for a full test
What is the most common indicator of activation of the short-term energy system?
?? - size of the intramuscluar ATP-PCr pool - depletion rates of ATP and PCr in all-out, short term activity
What two assumptions are used for feild tests of anaerobic power?
?? 1) all ATP at maximal power output regenerates via ATP-PCr hydrolysis 2) Adequate ATP and PCr exist to support maximal effort for about 6 sec duration
What is maximal voluntary ventilation? How can it be determined> Is it higher or lower than minute ventialtion during max exercise? What implications does this have?
?? Evaluates ventilatory capacity with rapid and deep breathing for 15 sec
WHich is more effective for lowering blood pressure: aerobic training or weight lifting?
?? aerobic training
How does the mode of exercise effect glycogen depeletion?
?? affects how quickly it is used
describe general myocardial metabolism (i.e. aerobic vs anaerobic) during rest, moderat exercisem and heavy exercise. Describe which fuels are used during each.
?? relies on energy released during metabolism, more energy required for more effort
Why does blood pressure increase so much during a bout od resistance training?
?? shuttling of blood
What is te quantiative relationship between cardiac output and VO2 max
A low maximal oxygen consumption corresponds closely with a low maximum cardiac output
Does max cardiac output or max a-vO2 difference increase more with strenuous aerobic exercise training over time?
Aerobic exercise makes Cardiac Output increase more than max VO2
Give the reation for CO2 transport as bicarbonate in the blood. What % is transported this way?
CO2 + H2O --> (Carbonic anhydrase)--> H2CO3 --> H+ + HCO3- - 60-80%
What three reasons listed in the text explain why the direct Fick method of measuring cardiac output is not very practical?
Complex methodlogy usually performed in hospitals - measuring oxygen consumption involves open-circuit spirometry - measuring a-vO2 difference requires a sample of arterial blood (any artery) and venous blood (from ventricle or pulm artery) - requires cardiac catherization
What muscles and structures are used to aid in aspiration?
Diaphragm, rib cage and abdominal muscles
If a person were to start an anaerobic power test with high intramuscluar glycogen levels, what effect would you predict this would have on the final level of lactate accumulation?
If you start high, you will burn through it fast and increase total amount of lactate accumulated
Do cardiac patients generally increase their capacity more from increased cardiac output or a-vO2 difference with training and rehabilitation?
Improve a-VO2 difference, dont want patients to push their cardiac output max during rehabilitation. but can help rebuild their muscles
Name the two major extrinsic control mechanisms of the heart?
Like we mentally prepare to be active so our hearts get ready - ventrolateral medulla: cardiac control center in brain - sympathetic and parasympathetic nervous systems also have an effect *nerves and chemicals
Ingeneral, do athletes increase their lung volumes with exerice training? What is the relationship between lung volume and VO2 max?
NO, there is no relationship
Give the equation for net energy expenditure
Net energy expenditure = groos energy expenditure - resting metabolism for the equivalent time
What concern is there when using heart rate to esitmate VO2 and energy expenditure?
Offers only limited practical benefits to predict oxygen consumption and caloric expenditure for most physical activities *each person has different realtionship b/w VO2 and HR, can vary from day to day *dehydration, stress, can change * also change with mode of exercise
What advantage is there for an older individual who engages in heavy resistance training and endurance training regarding RMR?
Offsets the decrease in resting metabolic rate that usually accompanies age
What are the partial pressures of oxygen and carbon dioxide in the alveoli?
Oxygen 103 mmHg Carbon dioxide 39 mmHg
What are the partial pressures of Oxygen, Nitrogen, and carbon dioxide in ambient air?
Oxygen 159 mmHg Carbon Dioxide 0.2 mmHg Nitrogen 600 mmHg
What are the abient air percentages for oxygen, nitrogen and carbon dioxide?
Oxygen 20.93% Carbon dioxide 0.03% Nitrogen 79.04%
What is TDEE?
Total Daily Energy Expenditure: dietary energy requirements of nongrowing individuals
According to Figure 11.2, how long does it take for the aerobic energy system to reach close to its maximal capacity? Can this change with training?
Varies depending on the energy system - immediate reaches maximal instantly - short term is maximal at 30 sec to 2 mins - long term would take over 10 mins *figures show it takes about 10 mins, you can increase that speed with training
What is the Windkessel Effect?
Windkessel effect is a term used in medicine to account for the shape of the arterial blood pressure waveform in terms of the interaction between te stoke volume and the compliance of the aorta and large elastic arteries (WIndkessel vessels) and the resistance of the smaller arteries and arterioles *stretching and recoiling of aorta
WHould it be more costly to carry additional weight on torso or on the ankles?
around the ankle has greater effect
What is the major controlling point for pressure and blood flow in the cardiovascular system?
arterioles
In the time course form the begining of exercise to maximal steady state exercise, when does the greatest increase in SV occur?
at the very begining of the exercise durration *almost immediately
Two lifters begin the same training program. One lifter increases strength quickly and the other does not increase strength at all. Is this most likely determined by genetics or by diet and recovery?
can be combo - if they work for a long time and no change that is not genetic (probably diet)
What is the exercise pressor reflex?
chemical stimulation of type IV afferent within active muscles
Why does upper body exercise at the same relative % of VO2 max result in higher blood pressures?
closer to heart, greater resitive blood flow in arms but less cardiac strain
Can 2,3 diphosphoglycerate be increased wih exercise training?
exercise decreases it
Describe the realtive and absolute blood flow to the kidneys during exercise with respect to at rest
goes from getting 20% of cardiac output during rest to 1% during exercise (going from 1100 mL the 250 mL)
What is the function and location of myoglobin? Does its concentration change with training?
in skeletal and cardiac muscle fibers, provides intramuscular oxygen storage
As a general rule, is running speed increased more by stride length or stride frequency
length
What types of soles reduce the energy cost of running?
lighter and softer soles shoes
What is the rate pressure roduct? How do we know it is directly related to myocardial work?
looks at peak systolic blood pressure and heart rate and is a good representation of cardac work
WHy is it more costly to run a given distance than to walk a given distance?
more cost to your body - less economical, no flight phase - in walking our body doesn;t move as much, while running our center of gravity changes as ge go
Approx. how much blood is contained in the fine network of blood vessels within the lung tissue at any one second of meximal exercise?
no more than one pint of blood flows within the delicate mesh network of lumg tissue blood vessels
What is the major difference between treadmill and track running
no wind resistance on a treadmill
Is the economy of walking linear with all walking speeds
no, exponential
Does deep breathing or increased breathing rate provide more effective alveolar ventilation?
no?
What is FEV1.0 / FVC ratio? What does it indicate?
reflects pulmonary expiratory power and overall resisitance to air movement upstream n lungs
At the same absolute level of submaximal exercise, what is the heart rate response for trained individual with respect to an untrained individual?
same absolute level, trained will have lower HR response
What is a varicose vein?
small one way veins that fail to stay one way, blood backs up
What two diferent ndices have been used to estimate RMR prior to the finding that RMR can be well estimated with lean body mass?
surface area and body mass
What is the Haldane Effect?
the interaction between oxygen lading and carbon dioxide releasing, faciliatates carbon dioxide removal in lung
What is alveolar ventilation? Why does alveolar ventilation not match minute ventilation?
the portion of inspored air reaching the alveoli and participating in gas exchange - prevents drastic changes in alveolar air composition to ensure consistency in arterial blood gases throughout the breathing cycles *what portion of air actually gets to the alveoli 350/500 mL, dead space takes up some
Describe coronary circulation in detail
through small arteries that feed heart muscles
Where is the CV control center?
ventrolateral medulla
What anatomical adaptation allows for an increase in cardiac output for a trained endurance athlete?
volume size of heart, size of ventricles (longer within chamber)
When does yoglobin facilitate O2 to the mitochondria?
yes, can change with training, but hard to proven, but has been proven in other animals so we assume
What is drafting? Does it really make much of a difference with running an event such as a marathon?
yes, plays a role - running behind competitor so they take on the wind resistance *can help save a lot of kcals per unit of time
What is generally the cause of post-exercise coughing?
Irritation that happens with respiratory water loss on the mucosa or epithelium in lungs
How is expiration achieved during rest and during heavy exercise?
It is a natural process that doesn;t require energy, during increase physical activity it can become more rapid with aid of muscles
What is dietary-induced thermogenesis? What are its two components?
It is an increase of energy metabolism while eating - Two components -- obligatory thermogenesis (specific dynamic actio/SDA) results from the energy required to digest, absorb, and assimilatte food nutrients -- facultative thermogenesis: relates to activation of the sympathetic nervous system and its stimulating influence on metabolic rate
When air enters the trachea, what is the main factor that changes?
It is completely saturated with water vapor, humidifes the air
What does low correlation between power test indicate?
It is hard to compare different test between different individuals, like energy expenditure is very task specific and person specific
What is ventilation-perfusion ratio? Give average numbers for during rest and during heavy exercise
It is the ratio of alveolar ventilation to pulmonary flow ??
What is the benefit to breathing 100% O2 when you are tired following strenuous exercise at sea level?
No benefit, blood is alreay at 98-99% O2 percentage, so breathing in pure O2 wouldnt help much *execption could be in humid weather breathing in dry O2 coud hep replace what the moisture in the air is filling
What is Henry's Law?
The mass of a gas that dissolves in a fluid at a given temp varies with the pressure of the gas over the liquid (provided no chemical reaction takes place between the gas and the liquid)
approx. how many kcals does a person expend per kg/km when running? What would this value be in kcal/lb/mile?
1 kcal/kg/km .75/kcal/lbs/mile
What is the purpose of hoving such an enormous surface volume in lungs (50-100 sq. meters or half a tennis court)?
To maximize absorption
Describe the pathway of blood from the systemic circulation, back to the heart, all the way through the aorta. Tell when it is oxygenated and when it is deoxygenated
*deoxygenated* right atrium -> right ventricle -> pulmonary arteries -> lungs *oxygenated* -> pulmonary veins -> left atrium -> left ventricle -> arota -> arteries -> capillaries *deoxygenated* -> veins -> superior/inferior vena cava -> right atrium
Give values for - cardiac output at rest - # mL O2/ liter of blood at rest - # liters of O2 delivered to the entire body at rest - # mL of O2 actually used by tissues each minute at rest - # mL of O2 reserved at rest (& released immediately upon demand)
- - - - - 750 mL
describe the waves of an ECG. What section of a normal ECG tracing correspond to each of these waves?
- *P wave: the forst ECG deflection, represents depolarization of both atria - P-R interval: the electrical transmission from atria to ventricles inclluldes the P wave and P-R segment - *QRS: Ventricular depolarization -- R wave indicated the initalpositive deflection -- Q wave is the negative deflection before the R wave -- S wave is the negative deflection folloeing the R wave - S-T segment: ventricular repolarization, extends from the end of the QRS to the strat of the T wave. The J (junction) point represents where S-T segment joins the begining of the T wave - T wave*: ventricular repolarization, S-T segment and T wave provide sensitive indicators of the ventricular myocardium's oxygen demand-oxygen supply status - Q-T interval: vertical repolarization and depolarization, basically the whole thing
How much O2 is carried per gram of hemoglobin? Based on this value, and the values from the previous, how many mL of O2 are in 100 mL of arterial blood for men vs women?
- 1.34 mL/gram men = 20.1 mL women = 18.76 mL
Describe the solubility of carbon dioxide with respect to oxygen
- Carbon dioxide dissolves most readily with a solubility coefficient of 57.03 mL of carbon dioxide per dL of fluid at 760 mmHg and 98.6 F (37 C) - Oxygen with a solubility coeffiecent of 2,26 mL, remains relatively insoluble
Define cardiac ouput. Explain the relationship between stroke volume and cardiac output.
- Cardiac output expresses the amount of blood pumped by the heart in 1min period - output dependson the rate of pumping (heart rate) and the quantity of blood ejected with each stroe (stroke volume)
What is 2,3 diphosphoglycerate? Where is it found? Is it higher in males or females?
- compund that binds loosely with the subunits of hemoglobin and reduces its affinity for binding with oxygen - in red blood cells - females have higher levels
Can a trained cyclists achieve max VO2 levels as high on a bike as they can on a treadmil?Can trained collegiate swimmers achieve max VO2 levels as high in a pool as they can on a tramil? What about elite swimmers?
- cyclists = yes or extremely close - swimmers cant acheive same in pool, b/c pool supports body weight so postural muscles dont have to work
Describe the indicator dilution method of measuring cardiac output? What dye is often used?
- Indocyanine green dye - inject known amount of dye into vein and follow it throughout the body using light, b/c it binds with plasma proteins and/or red blood cells
What two restrictions are given to a person before testing BMR?
- Must be in postabsorptive state (fasting) without food consumed for the 12 to 18 previos hours to avoid increase in metabolism from digestion, absorption, and assimilation of ingested nutrients - no physical activity for a minimum for 2 hours to the assessment
Give pressure gradients for oxygen and carbon dioxide at the lung.
- Oxygen going from 100 mmHg inside to 40 mmHg outside - CO2 is 40 mmHg inside and 100 mmHg outside
What two classification systems mentioned in class are used to quantify the difficulty of an exercise bout?
- Physical Activity Ratio, broad categories of work (PAR) - MET, more scientific, looks at oxygen consumption
What are the terms for speeding of heart rate and slowing of heart rate respectively? What is the primary controlling mechanis for slowing the heart?
- Tachycardia = fast heart beat - bradycardia = slow = controled by vagus nerve
Define partial pressure. Give the equation for determining partial pressure.
- The molecules of each specific gas in a mixture of gases exert their individual partial pressure, the mixture's total pressure equals the sum of the partial pressures of the individual gases in the mixture - Partial pressure = percentage concentration of specific gas * total pressure of gas mixture
What is three general factors that influence TDEE?
- Thermogenic effect of feeding - thermic effect of physical activity - resting metabolic rate
Define the following: - Tidal volume - Inspiratory reserve volume - Expiratory reserve volume - total lung capacity - residual lung volume - forced vital capacity - inspiratory capacity - functional residual capacity
- Tidal volume (TV): air volume moved during either inspiratory or expiratory exchange phase - INspiratory reserve volume (IRV): dditional that can be inhaled - Expiratory reserve volume (ERV): additional that can be exhaled - Total lung capacity (TLC): = RLV +FVC - Residual lung volume (RLV): represents the air volume left that keeps lung shape - Forced vital capacity (FVC): = TV + IRV + ERV - Inspiratory capacity (IC):?? - Functional residual capacity (FRC):??
What three factors affect air resistance?
- air density - runner's projected surface area - square of wind velocity
Why do women expend less energy than men to swim the same distance? On average, how much difference exists between the energy costs of swimming a particular distance for men vs women
- body bouyancy - women at 30% lower
What are two proposed mechanisms by which residual lung volume changes after an acute bout of short or long term exercise?
- closure of small peripheral airways - increase in thoracic blood volume
give two explanations for why coronary blood flow greater during diastole than during systole?
- during diastolye lots of pressure in the aorta - heart muscle is relaxed
What three main factors contribute to the individual differences in the capacity for anaerobic training?
- efffects of previous training - capacity to buffer acid metabolites - motivation
Describe the integrated response of the CV system with exercise
- feed forward - central command - regional blood flow changes with intensity - medulla - local metabolic factors - Vasoconstriction at bunch of active tissues
at the same submaximal VO2 level, why would upper body exercise result in greater heart rate, pulmonary ventilation, and perception of effort?
- greater amount of feed forward even if total amount of work is being produced - greater feedback because peripherial receptors, more in lower body - perception of effort and feedback
Define afterload. How can greater systolic emptying be achieved despite an exercise-induced increase in afterload?
- greater systolic ejection occurs despite increased resistance to blood flow in the arterial circuit from exercise induced elevation of systolic blood pressure - occurs because the ventricles always contain a functional residual blood volume *afterload = pressure necessary to push blood to the aorta *Lower end systolic volume (blood left in the heart), typically happens b/c catecholamines beacuse heart will squeze harder and push more - which a healthy heart is capable of
How does RMR in individuals from tropical climates compare to those in cold climates? Why? In specific situations can cold climate elevate RMR?
- in tropical climaes are 5 to 20% in RMR - cold environments generally increase energy metabolism during rest and physical activity - metabolic rate increases up to fivefold at rest during extreme cold stress because shivering generates body heat to maintain core temp *warmer environments, hormone change, especailly thyroid *if its cold, any shivering = RMR increase
At rest, only 1 of 30-40 capillaries in muscle tissue remains open. Name three important functions of keeping the remaining dormant capillaries open during exercise.
- increased total muscle blood flow - delivers a large blood volume with only minimal increase in blood flow velocity - increases the effective surface for gas and nutrient exchange between blood and muscle fibers
What is the function of pre-capillary sphincter?
- it is a ring of smooth muscle that encircles the vessel at its orgin, controls capillary diameter - regulates blood flow
What is the myocardium> How are the cells of the myocardium synchronized?
- it is the heart muscle - homogeneoud form of straited muscle fibers that are slow twitchm that are multinucleated and have intercalated discs
What four methods are used to physiologically evaluate the ATP-CP system?
- look at total amount of muscluature - creatine depeltion rates in response to all out exercise - oxygen defiect from curve - fast component of recovery oxygen uptake -- all hard not very accurate -estimating size of pool
To what degree does heredity control aerobic and anaerobic capacity?
- lots of hereitary control, higher in anaerobic, more likely to be born good at that b/c hard to train to get better at it - aerobic not so much
Define and give the equation for computing mechanical efficiency
- muscle efficiency reflects the percentage of total chemical energy expended that contributes to external work, with the remainder lost as heat "mechanical efficiency (%) = external work accomplished / energy expenditure * 100"
approx. what % of the power generated in cycling is used to overcome air resistance? How much can drafting help?
- normal is 90% of energy expenditure is overcomeing air resistance -that is reduced by 26-38% with drafting
DO overweight individuals have a greater or lesser dietary-induced thermogenesis? Do well trained athletes have greater or less response?
- overweight individuals ofter have a blunted thermic response to eating that contributes to excess body fat accumulation - physically active people, DIT represents only a small portion of TDEE compared with energy expenditure through regular physical activity *both have lesser - overweight is blunted, so dont heat up as much and dont use it (it is stored) - well trained is also lower b/c hormonal, conservation goes to storage in prep for nest exercise bout
Why is energy expenditure so much greater in water temps below 77*? Why wouls a lean swimmer suffer more from this effect? What range of water temp is ideal dor most lean swimmers?
- places body under thermal stress, body is also trying to warm itself, sendning blood in, when the muscles need it out - 82-86*
What three methods are used to measure energy expenditure of swimmers during long swims? How does this differ from short swims?
- portable gas-collection equipment - swimming treadmill - tethered cable --not sure about short swims--> short swims hold breath for 25 yrds, and look at oxygen recovery for next 20-40 mins
What is pulmonary circulation vs. systemic circulation? What makes the pulmonary artery and vein different from the other arteries and veins>
- pulmonary circulation is through the lungs while systemic goes through the body - pulmonary artery and vein are different than the rest of the body because while arteries are normally oxygenated and veins are deoxygenated, the pulmonary veins are oxygenated and the arteries are deoxygenated
What two actions mentioned may allow exercise to alleviate hypertension>
- reduced activity in CNS - altered renal state
What determines the max level of aerobic work in a well trained athletes? What limits max level of aerobic work for a sedentary person?
- same limitations in both populations - oxygen transport coupled with muscles ability to use it... limits exercise - person who is untrained will have local fatigue due to accumulation of metabolites
What ergogenic aod can be used to increase the buffereing capacity of our blood?
- sodium bicarbonate, can help but most cant use b/c cause GI issues , but can be very powerful
Explain why systolic blood pressure and diastolic blood pressure estimate myocardial work and total peripheral resistance respectively
- systolic is measured whn heart if contracting, how hard did it pump - diastolic, being maintained when heart is relaxed so the vessels hold the pressure
Define arterio-venous oxygen difference? Give values at rest and during strenuous exercise.
- the difference of O2 content in arteries vs in veins - Artaries is 20 mL - veins about 15 mL - so the difference at rest is about 5, but during activity this can be increased to 15 because more will be used up and less will be found in veins
Describe the relatioship between ventricular complience, diastolic stiffness, and stroke volume. How are these varibles affected by enduance exercise training? How are they affected by myocardial ischemia?
- ventricular complience (how willinf it is to recieve, stretch) - Diastolic stiffness is the opposite - Stroke volume depends on the above - Ishchemia results in stiffness = a lack of blood flow or O2
When does it reach its maximum, and what % of the ingested food is used for deitary-induced thermogenesis?
-10 to 30% of ingested food energy - maximum??, can depend on what you ate
Define - interventricular septum -strioventriculsr valve - mitral valve What are the second names?
-Interventricular system: system within the heart - Atrioventricular valve: valve b/w atrium and venricles (tricuspid valve) - mitral valve: bicuspid valve
What local regulatory factors, in addition to sympathetic nervous system hormones, help dilate coronary blood vessels during esercise?
-tissue hypoxia - adenosine from ATP breakdown is a powerful regualtor
How long does it take for gases at the lung to equilibriate? Is this enough time during heavy exercise?
.25 sec yes it is enough time
List 6 factors from your text that affect maximal oxygen uptake
1) Mode of activity 2) Heredity 3) State of training 4) Gender 5) Body size and composition 6) Age
Name three factors listed that can affect a-vO2 difference during exercise following training
1) redirect blood to where we need it (effeicency) 2) microcirculation is more developed - more capillaries 3) larger and more mitochondria
What are the two methods for transport of oxygen in the blood?
1. In physical solution dissolved in the fluid portion of blood 2. In loose combination with menoglobin, the iron-protein molecule within the red blood cell
List four limitations to the HR-VO2 max relationship
1. Linearity of heart rate-oxygen composition or exercise intensity relationship 2. Similar maximum heart rates for all subjects 3. Assumed constant economy and mechanical effeciency during activity 4. Day-to-day heart rate variation
What is the partial pressure of oxygen in the trachea?
149 mmHg
How many grams of hemoglobin are found in each 100 mL of blood in men vs women?
15 g in males 14 g (5-10% less) in women
What % of TDEE is accounted for by physical activity?
15 to 30%
Give a normal range of #'s and describe what BMR is most dependent upon.
160-200 mL/min (0.8 - 1.43 kcal/min) - depends on gender, age, overall body size (stature and body mass) and fat free body mass (FFM) *smaller ppl @ 160 *larger ppl @290 *typical average @250
What is the approx. efficency for walking, running, and sationary biking?
20-25%
approx. what % of the energy expended in running is accounted for by air resistance?
3-9%
What is a-vO2 difference? Provide typical values for a person at rest.
5 L/min at rest to 100 L/min active
On average, approx. what % varience exisits in an individual's VO2 max value depending on their current state of training>
5 to 20%
What is the range of mechanical efficency fir swimmers> How does this compare to runners?
5-9.5% ?? on compare??
At what % of VO2 max does SV reach it approx. peak?
50%
At what age does VO2 max begin to decline? Can this be attenuated with training?
55
At what % of VO2 max does lactate begin to accumulate?
55%
At what speed does a change of gait from fast walking to running maintain a lower oxygen cost? (at least for competitive walkers)
7.2 - 7.4 km/hr
What volume of blood flow travels through the coronary circulation per minute at rest? What % of oxygen is extracted from this blood? What implication does this have for myocardial blood flow during exercise?
70-80%
Approximately what % of the average US citizen's day is consumed with light expenditure of energy?
75%
What is minute ventilation? Give average minute ventilations for: 1) an average person at rest 2) normal young adults during strenuous exericse 3) well-trained male endurace athlete of large stature
= breathing rate * tidal volume *ventilation over period of I min 1) 6 L/min 2) 100 L/min 3) 195 L/min
Why might residual lung volume change with age?
?? smaller weaker muscles
What is "fee forward" and when is it active?
?? anticipatory response to activity
Do women and children have the same anaerobic short term capacity as men?
?? no
At rest, approx. how much of the tidal volume with each breath is not fresh air? How much is fresh air?
???
How would you describe myocardial oxygen utilization with respect to myocardial blood flow for an individual at rest?
???
In exercies physiology, the variation among people with regard to their metabolic and physiological capacities is often reffered to as ___________________________.
???
WHat is phlebitis?
???
What is released from adrenergic fibers, and what is the effect on blood vessels? If there is no consistant evidence of cholinergic sympathetic fibers in humans, how is vasodilation achieved in active musculature?
??? - release norepinephrine, as a vasodilator - dilations occurs from reduces vasomotor tone (which is caused bu the constriction) *norepinephrine *smal vasodialtion from ACh from neuromuscluar junction * powerful vasodialtion from byproducts of exercise
DOes an acute about of exercise increase or decrease the dietary induced thermogenic response? What implications does it have?
??? yes, minor effects *increase, implication would be eating a meal before actiivtiy would help burn more calories
WHat is hypertension and what factors can cause this disease state?
Abnormally high blood pressure - "hardening" with fatty materials deposited within their walls or b/c the vessel's connective tisse layer has thickened - offer excessive resistance to peripheral blood flow b/c of neural hyperactivity or kindey malfunction
Examine the distribution of blood flow during rest? Which organs increase their absolute blood flow during exercise? What about relative? Liver and Kidney?
Absolute = muscle relative = heart, brain, skin, other - kindeys and liver go way down in blood flow, non-essential for exercise
What would happen if all of the vessels in our body dialted at the same time? What does this imply in terms of capacity of the CV system with respect to blood volume?
All dailated we would pass out, blood would ool between out thighs and feet, because our bodies dont hold enough blood to fill our total capable volume
What advantage might exercise training afford to an athlete with respect to ventilatory enduarnce?
All muscles that are used for breathing can be trained to get better , but wont unless you try
What is the refractory period of the ECG and what function does it serve?
Allows significant time betwen beats for sufficient ventricular filling
What is BMR?
Basal Metabolic Rate: reflects the sum total of the body's many avenues for heat production
Define preload. What can account for an increase in preload?
Any factor that increases venous return or slows the heart produces greater ventricular filling (preload) during the cardiac cycle's diastolic stage - increase in end-diastolic volume, strech myocardial fibers
Why can trained individuals tolerate higher levels of lactic acid before the onset of fatigue?
Basically all have same buffering capacity, athletes increaseed ability comes from motivation
What types of environment are helpful to an asthmatic? What environments are detrimental?
Benefical: warm and humid?? ???
Give the equations for blood pressure and mean arterial pressure? Why is DBP weighed more heavily in the equation?
Blood pressure = cardiac output * total peripheral resistance - MAP = diastolic BP + [0.333 (systolic-diastolic)] - diastolic represents the peripheral pressure
Why is blood pressure lower during recovery from low and moderate intensity exercise?
Blood remains in peripherim, maintained dialation
WHy is it not necessaryily accurate to strictly apply (quantitatively) the physical laws relating pressure, volume and flow to the CV system?
Body vessels are not cylindircal tubes and blood is not homogeneous throughout
What does the sympathetic nervous system release at the heart? What 2 effects does this have on the heart?
Catecholamines (epinephrine and norepinephrine) - they accelerate the SA node depolarization, cuasing heart to beat faster (Chronotropic effect) / tachycardia - also increase myocardial contractility (inotropic effect) to augment how much blood pumps with each beat
What is the result of CO2 binding with hemoglobin?
Carbaminohemoglobin
GIve the Fick equation. Use this equation to show average cardiac output of a person at rest.
Cardiac output (mL/min) = ((VO2 mL/min)/(a-vO2 difference [mL per 100 mL blood]))*100 - at rest CO= (250 mL O2/ 5mL O2)*100 = 5000 mL blood
What one mode of exercise can usually be used to determine VO2 max for almost all athletes?
Cross country skiers
What are Conducting Zones (atomic dead space)?
Conducting zones (1-16) includes the trachea and terminal bronchioles (air transportation) - air transport - humidifcation - Warming - particle filtration - vocalization - immunoglobulin secretion(
What is the best criterion to determine if VO2 max has been achieved? What is VO2 peak?
Demonstration of a leveling-off or peaking-over in oxygen consumption with increasing level of exercise intensity generally provides assurance that a person has reached maximum aerobic metabolism
What is depolarization and repolarization?
Depolarization: in atria then ventricles, causeing contraction, P wave Repolarization: the T wave, repolarization of ventricles, refers to the change of the membrane potential that returns the membrane back to a negative value
What is physiologic dead space?
Describes the portion of the alveolar volume with a ventilation-perfusion ratio that approaches zero
What is pulmonary ventilation?
Describes the process of moving and exchanging ambient ait with the air in the lungs
Describe the mechanics and function of the Valsalva Maneuver?
Diminish brain blood supply?
Characterize the early and late responses with an exercise-induced asthma attack
Early: air passage becomes smaller from bronchial spasm and edema Late: greater inflammation increased bronchial constriction, mucus secretion, and edema * hyper irritability *Bronchiole spasm *edema *- mucus secretion *chest tightness, shortnesss of breath, coughing, wheezing
In stair-sprinting power tests, what three variables are needed to calculate power? What are the units
F in kg D in m T in sec
How would you predict max VO2 in an individual who should not perform maximal effort for fear of injury?
FInd submaximal and lot hr vs vo2 max and use tread line as projection to find VO2 at (HR 220- age)
Describe Fick's Law
Fink' Law of diffusion governs gas diffusion across a fluid membrane, two-part law states that a gas diffuses through a sheet of tissue at a rate (1) directly proportional to the tissue area, a diffusion constant, and the pressure differential of the gas on each side of the membrane (2) relates directly to the gas solubility (S) and inversly to the square root of the gas molecular weight
What is the most important factor in Poiseuille's Law?
Flow = (pressure gradient*vessel radius)/(vessel length*fluid viscosity)
Give the reaction between CO2 and bicarbonate ion at the tissue; at the lungs
H+ + HCO3- --> H2CO3 --> (carbonic anhydrase) --> CO2 +H2O
What is cooperativity?
How well oxygen and hemoglobin work together
What effect does long-term aerobic training have on heart rate during rest and moderate exercise? How is this mediated?
Induces bradycardia - creates greater dominats of parasympathetic (rest and digest)
What is the Bohr effect?
Indicates that hydrogen ions and carbon dioxide alter hemoglobin's molecular structure to decrease the oxygen-bonding affinity
What is the chloride shift?
Increase the Cl-content of erythrocytes in venous blood more than in arterial red blood cells, Particularly during exercise *allows for bicarbonate ion to leave and be replaced by chloride
What two very importants exercise variables addresses in class help determine the perceived difficulty of a particular exercise bout?
Intensity and duration represent two importan factirs that impact the relative strenuousness of a particular physical task
What is unique about alveolar tissue with respect to blood supply?
It receives the largest blood supply of any of the body's organs
What factors brought about the deleopment of predictive measures for VO2 max?
Lab tests from medical clearence
What general type of exercise is recommended for therapy for cardiovascular disease when considering blood pressure responses?
Large body exercises that are rythmic (cycling, even if it is slow)
What advantage does rhythimic steady-rate exercise afford for varicose veins?
Maintain strength
Give average #'s for males and females with respect to maximal voluntary ventilation
Males 140-180 L/min Females 80-120 L/min
What specifi skeletal muscle physiological variable is correlated to the economy of cycling?
Muscle with high percentage of type 1 fibers, the vastus lateralis muscle
How is movement economy deterined?
Movement economy refers to the energy required, usually inferred from measurement of oxygen consumption, to maintain a constant moevment velocity
Where is PCO2 sensed?
Pons and medulla centers of brain stem
Give the equation for "Power"
Power = (Force*Distance)/Time
Give the equation for estimating RDEE from fat free mass (i.e. lean body mass)
RDEE (kcal) = 370 + 21.6(FFM (kg))
What % of TDEE is accounted for by RMR and themic effects of feeding respectivley?
RMR is 60 to 75% of TDEE Thermic effect is approx. 10%
What is RMR?
Resting Metabolic Rate - measured 3-4 hours after light meal and no prior activity, is slighty lower than BMR
Describe the conduction of an impulse from the S.A. node through the rest of the heart?
SA --> AV --> AV bundle --> Purkinje fibers
What are pores of Kohn? What function do they serve?
Small pores within each alveolus evenly disprese surfactant over the respiratory membranes to reduce surface tension for easier alveolar inflation, the pores also provide for gas interchange between adjacent alveoli
why would a person exercising with only the upper body exhibit greater oxygen consumption at the same level of power output with respect to that which would be seen during lower body exercise?
Still working their body
What limitation is involved with interpretation of stair sprinting power tests? Does external power output correlate to a well-developed ATP-CP system?
THis system is bias because it would indicate that a heavier sperson would have higher power score, it is hard to compare people of different sizes
Is there specificity of aerobic and anaerobic capacities or is it a general trait? In other words, if you are an excellent runner because you have "good wind", will you also be a great cyclist due to the "good wind"?
There is a specificity to it they are different systems so what makes you good at one may not apply to others *some carryover, cause good atheltes are just good athletes *however there is a specificity to sports that wont carry over 100%
If a person jogs 9 miles in 1.5 hours and another person of the same mass runs 5 miles in 30 mins, who burns more calories?
What are the two modes - jogging 9 miles is at slower pace but much longer so they probably burn more
WHat is the isovolumetric period?
When heart volume and muscle fiber length remain unchanged, during brief interval of rising ventricular pressure
What explanation might be provided for a female's cardiac output being 5-10% greater with respect to a male's cardic output at the same level of submaximal exercise?
Women have 10% lower hemoglobin concentration, meaning our blood flows a little less frictionally and more can be moved (also thinner)
What is a-vO2 difference during exercise for an untrained person during maximal exercise? Approx. how much can it change, and how ong does it take to increase the a-vO2 difference with training?
Would take a long time but you could get it to 15-16 maybe even 17 or 18 with two months of training
What factir besides horizontal movement (which includes drag forces) contributres to the energy demand of swimming>
a considerably lower mechanical efficency makes the energy expenditure during swimming a given distance average babout four times greater than the energy expenditure running the same distance
What harmful effect can body inversion cause?
a lot of increased BP in vessels that does usually get it (head neck chest, feeling pressure that feet feel normally)
At the tissues what does CO2 react with to form a carbamino compund?
amino acids molcules in blood proteins
What is anemia? How does it affect performance?
anemia is ?? - it does affect oxygen transport
Why might a weel trained athlete have a very low basal heart rate?
athletes have a larger blood volume = bigger stroke volume and lower heart rate *ventral lateral medulla
name several local factors in muscle which control regional blood flow
blood supply in tissues blood content
What effects do body mass and terrain have on energy expenditure?
body mass does have and effect in how much energy is spent - landscapes may vary
Give the equation used in calculations of cardiac output with the CO1 re-breathing technique. What are the benefits of this method of measuring cardiac output? Name one limitation.
cardiac output (mL/min) = VCO2/v-aCO2 difference *100 - does not require blood sampling or intense medical supervision, and minimal implications of movement -- requires subjects to exercise under a steady-rate aerobic metabolism; this resticts the method's use during maximal and "supermaximal" activities and in the transition from rest to exercise
WHy does blood flow to the skin increase during exercise in hot humid weather if it seems that we could use all of our blood for oxygen transport to the active muscles?
cooling system, trying to send blood to outside to cool it and bring it back inside to core
What is vasomotor tone?
decreased adrenergic activity
Describe the relevance of research addressing coratid artery palpation for monitoring heart rate? What implication may it have for cardiac patients?
external pressure on carotid can slow heart rate - gives false sense of how hard you have been working, false feed back
From what tissues does peripheral input originate to control heart rate and circulation?
from peripheral receptors in the blood vessels, joints, and muscles - specifically chemoreceptors and mechanoreceptors within muscles
What general effect does body mass have on the energy expenditure of weight-bearing exercises?
heavier individuals expend more total energy in physical actiivty than lighter counterparts, particularly in weight-bearing walking, climbing, and running activities
What two methods are used to determine residual lung volume?
helium dilution method or oygen dilution
How do systolic and diastolic blood pressures respond to continuous graded treadmill exercise?
increase at first and then level off
How does the autonomic nervous system control an increase in heart rate with exercise?
increase sympathetic drive
What exercise variables determine the degree of activation of sympathetic cardioaccelerator nerves?
intensity and duration of effort
Why don't we only use the epinephrine released from the adrenal glands to increase heart rate and contractility via the endocrine system?
it goes to the whole body not just the heart
is it more costly to under-stride or over-stride while running? Is this generally something that needs instruction
it is more costly to go under the average; typically doesnt need instruction, people naturally fall into stride or increase stride to adjust
Why don't we see a wave that sorresponds to atrial repolarization
its hidden by larger things that are going on
Why is the diffusion of gas at the lung so fast?
large pressure differentials, also massive surface to volume ratio
What accounts for an increase in energy expenditure when walking quickly downhill?
take more energy to work against gravity even though not breathing as hard
What is cardiovascular drift? What variables contribute to cardiovascular dirft?
the gradual time-dependent downward "drift" in several cardiovascular responses, most notably stroke volume with concemitant heart rate increase during prolonged steady-rate exercise, particularly at high ambient temps
when exercising with only the upper body, why do we exhibit blunted responses in terms of max O2 uptake, max heart rate, and max pulmonary ventilation?
the return from the lower half of the body dulls the resulting tests
Give average values for cardiac output, HR and SV of an untrained college-aged male in resting state. How would these values cpmare to a similar age female? How does these compare to a trained athlete?
the vlalues of trained and untrained athletes at rest are similar - women are usually 20% less than men
What practical recommendations could you give a friend who is trying to lose weight if they have complained that walkin is much to easy and running causes shin-splints (tibia stress syndrome)
they can walk wearing weight, around torso will add weight without sacrficinf technique - ankle weights can negativly affect gate
WHy are children 20-30% less econmical than adults when running at the same speed?
they require more oxygen
WHat is one very important limitiation in methodology for the jumping power tests?
this extremely brief period of muscle activation probably does not adequately evaluaate a person's maximal ATP/PCr energy transfer capacity *really hard to eliminate skill factor
If a person loves swimming and hates running, how far would you tell them to swim wach day if they told you they wanted to burn 400 calories/day exercising and they weigh about 150 lbs?
to run/jog a mile = 100 calories tel them to swim a mile (4x cost) = 400 calories, would also take a lot longer
How long is a test for anaerobic power for the short-term energy system?
up to 3 mins
What two practical methods can be used to reduce swim drag forces?
wetsuits drafting (close or far from lanes)
What is the average difference in VO2 max between men and women? What two factors typically contribute the most to this difference?
women are typically 15-30% below men - body composition and hemoglobin concentration
