Ex Phys Ch. 11
3 metabolic adaptations to training:
LT RER O2 consumption (VO2)
Long-term improvement: performance continues to increase after VO2max plateaus because:
LT continues to increase with training
How does the LV respond to endurance training? What does this allow for?
LV chamber size increases. increased LV filling and consequent increase in SV
what limits aerobic power and endurance performance?
The oxygen supply. O2 transport and delivery to the working muscles limits VO2max.
How are type II fibers affected by endurance training?
Type IIx --> more oxidative (type IIa)
write out fick equation for both VO2 and VO2max:
VO2 = Q x (a-v)O2 diff VO2max = Qmax x max(a-v)O2 diff
LV mass is highly correlated with ___
VO2max
best objective lab measure of cardiorespiratory endurance
VO2max
The combo of ___ HR and ___ SV is a more efficient way for heart to meet metabolic demands of exercising body. How?
decreased, increased heart expends less energy by contracting less often but more forcefully than it would if contraction frequency were increased
after training, what happens to RER? what are these changes attributable to?
decreases at both absolute and relative submax exercise intensities. attributable to a greater utilizaton of FFAs instead of carbs at these work rates following training
CR endurance is related to the CV and respiratory systems' ability to ___
deliver sufficient O2 to meet needs of metabolically active tissues
What happens to Q at rest and during submax intensities as a result of training?
doesn't change much, may decrease slightly
effect of endurance training on resting BP in healthy subjects: hypertensive:
doesn't change significantly in healthy subjects. modest reductions in hypertensive subjects
In the HERITAGE study, the small decrease in VO2 during submax exercise could have resulted from an increase in exercise ___ (performing the same exercise intensity with less extraneous movement)
economy
Other factors that influence HR recovery time:
elevated core temp or enhanced SNS response can prolong HR elevation
after training, there appears to be a small ___ in type I fibers. What happens to type II fibers?
increase type IIx --> type IIa (become more oxidative)
The combo of increased capillarization and capillary recruitment work to do what?
increase CSA for exchange b/w vascular system and active muscle fibers
What is the reason Q may decrease slightly after endurance training at rest and during submax exercise? (2)
increase in a-vO2 diff (greater O2 extraction by tissues) or decrease in rate of O2 consumption (increased mechanical efficiency).
the increase in blood volume as a result of endurance exercise primarily results from ___, but there is also a(n) ___
increase in plasma volume increase in volume of RBCs.
To summarize, ___, ___, and ___account for the increases in resting, submax, and maximal SV after an endurance training program
increased LV dimensions decreased TPR increased blood volume
What's effect does endurance training have on submax endurance capacity? What physiological variable can be used to objectively quantify the effect of training on submax endurance capacity?
increases it. HRss should be lower at the same submax exercise intensity
what effect does aerobic training have on VO2max?
increases substantially
improvement in endurance performance without improvement in VO2max is likely attributable to improvements in the ability to perform at:
increasingly higher percentages of VO2max for extended periods
the magnitude of the increase in type I CSA depends on the ___ and ___ of each training bout and the ___ of the training program. Increases in CSA of up to ___% have been reported
intensity, duration length 25%
How does the LV respond to resistance training? Why?
it must contract against and overcome increased afterload from the systemic circulation (increased BP during RT). Heart muscle compensates by increasing LV wall thickness, thereby increasing contractility. There is little change in ventricular volume.
the more sedentary an individual is when starting an exercise program, the ___ the increase in VO2max
larger
how does SV compare in large and small person? why?
larger = higher smaller = lower large person has larger heart, greater blood volume, and higher SV
During an intense exercise bout, what do proteins do? How are they returned?
leave vascular space and move into the interstitial space. returned in greater amounts through the lymph system
The ___ does the most work and thus undergoes the most adaptation in response to endurance training
left ventricle
Ventilation is not usually a(n) ___ factor for endurance exercise performance
limiting
unlike what happens with the CV system, endurance training has ___ effect on lung structure and function
little
What adaptations occur in the ATP-PCr system with anaerobic training?
little enzymatic change with training
In concert with this, a decrease in RHR caused by increased parasym. tone, and during exercise at the same work rate, allows a(n) ___. What does this do?
longer diastolic filling period
healthy untrained girls and women have significantly ___ VO2max values than healthy untrained boys and men. Highly conditioned female endurance athletes have values much ___ to those of highly trained males endurance athletes.
lower closer
training effects on submax HR:
lower HR at any given absolute exercise intensity
how do you improve mitochondrial density? how do you do this?
make existing ones larger do this by increasing oxidative enzymes (SDH and citrate synthase)
generally, Q ___ O2 consumption required for any given intensity of effort
matches
___ and ___ have both been used as indexes of anaerobic capacity
mean power output total work
describe the training-induced decrease in submax HR at higher intensities:
the decrease is typically greater (more noticeable) at higher submax intensities
How do the effects that 20 mins of jogging/cycling have on oxidative enzyme activity compare to that of vigorous training (60-90 mins)?
the higher the intensity, the greater the influence on enzyme activity
nearly all of the increase in blood volume during the first 2 weeks of training can be explained by ___
the increase in plasma volume
what does the fick equation state?
the rate of whole body O2 consumption (VO2) is determined by both the delivery of O2 via blood flow (Q) and the amount of O2 extracted by the tissues [(a-v)O2 difference]
What has been proposed as one reason highly trained endur athletes have lower HRmax values:
their hearts have adapted to training by drastically increasing their SV, so lower HRmax values can provide optimal Q
what happens to anaerobic power and anaerobic capacity with anaerobic training? results varied ___ across studies
they both increase widely
why would an endurance athlete include RT as part of the total training program?
to increase, or at least maintain, basic strength levels, as well as some sprint training to facilitate their ability to sustain speed when needed (sprinting across finish line)
each person is born into a predetermined genetic VO2max window, and the person can shift up or down within that window with exercise ___ or ___, respectively
training detraining
Why doesn't the respiratory system function usually limit performance?
ventilation can be increased to a much greater extent than CV function
The O2 content of arterial blood changes ___ with endurance training. Even though total Hb is ___, the amount of Hb per unit of blood is __ or ___
very little increased, the same, slightly reduced
the increase in mitochondria in response to endurance training is ___ dependent. What is this similar to?
volume hypertrophy in muscles
What's the closest to gold standard for anaerobic power test? what's this used to measure?
wingate anaerobic test anaerobic power
The endurance training-induced increase in stroke volume is also seen at a given ___ exercise intensity and at ___ exercise
submax max
things that increase SV after aerobic training: (2)
-LV fills more completely during diastole and plasma volume expands allowing more blood to enter ventricle during diastole, increasing EDV. -HR lower at rest and at same absolute exercise intensity, allowing more time for the increased diastolic filing
The increase in a-v O2 diff is attributable to a more effective ____ and an increased ___
-distribution of arterial blood away from nonactive tissue to the active tissue -ability of active muscle to extract O2
how does training effect ventilation at rest? submax? max?
-essentially unchanged at rest -decreases ventilation during submax exercise by as much as 20-30% at given submax intensity -max ventilation substantially increased
What was the conclusion of the twin VO2max research? what does this mean?
-heredity accounts for 25-50% of the variance in VO2max values -means that of all factors influencing VO2max, heredity alone is responsible for one quarter to one-half the total influence.
What has recent research shown regarding identical (monozygous) and fraternal (dizygous) twins and VO2max?
-identical twins have similar VO2max values -variability for fraternal twins is much greater
What major adaptations occur in muscle as a result of anaerobic training?
-increase in type IIa and IIx cross-sectional area, increase in type I CSA but to a lesser extent -reduction in percentage of type I fibers and an increase in the percentage of type II fibers, with the greatest change in type IIa fibers
4 factors that account for enhanced blood flow to muscle following training:
-increased capillarization -greater recruitment of existing capillaries -more effective blood flow redistribution from inactive regions -increased total blood volume
What adaptations occur in the glycolytic system with increases in anaerobic training? What are performance gains derived from?
-increased glycolytic enzyme activity with training (PFK, LDH, hexokinase) -derived from increase in strength rather than the anaerobic yield of ATP.
how is the a-v O2 diff affected by endurance training? What does this result from? what does this reflect? (2)
-increases, particularly at max exercise intensity. -results from a lower mixed venous content, which means that the blood returning to the heart contains less O2 than it would in an untrained person. -reflects both greater O2 extraction by active tissues and a more effective distribution of blood flow to active tissues
how does training status affect a person's response to aerobic training? what's this called?
-the higher the initial state of conditioning, the smaller the relative improvement for the same volume of training. -The more sedentary the individual, the greater the improvement in training response -law of initial values -this is why we recruit sedentary ppl to participate in studies
twin VO2max graph: what does the LOI represent? what are the axes labels? are the axes relative or absolute? what exercise modality was used and how long did the test take?
-x = y; a dot on the line would represent the same VO2max for both brothers. -x = brother A's VO2max (ml/kg/min) y = brother B's VO2max (ml/kg/min) -relative -all out, 90 min ride on a cycle ergometer
2 mechanisms thought to increase plasma volume with training:
1- increase in plasma proteins, particularly albumin. 2- exercise increases the release of ADH and aldosterone
max ventilation substantially increased from a rate of about ___-___ in untrained person to about ___-___ or more following training. Ventilation rates typically increase to about ___ in highly trained people and can exceed ___ in very large, highly trained endurance athletes.
100-120 L/min 130-150 L/min 180 L/min 200 L/min
long term improvement in aerobic power and CR endurance: although one's highest attainable VO2max is usually achieved within ___-___ months of intense endurance training, endurance ___ can continue to improve.
12-18 performance
Qmax ranges from ___-___ in untrained individuals and from ___-___ in trained ppl, and can be ___ or more in highly conditioned endurance athletes. These absolute values, however, are greatly influenced by ___
14-20 L/min 25-35 L/min 40 L/min body size
VO2max: typically, an increase of ___-___% is typical for a previously sedentary person who trains at 50-85% of his or her VO2max 3-5x/wk, 20-60 min/day, for 6 months.
15-20%
Figure 11.1: Represent increase in VO2max after 12 months of aerobic training in a previously untrained individual. VO2max increased by about ___%. The VO2 "cost" of running at a submax intensity (running ecomony) did not ___, but higher ___ could be attained after training.
30 change running speeds
SV at rest of untrained person: trained?
50-70 ml/beat 70-90 ml/beat
In fully mature athletes, the highest attainable VO2max is reached within ___-___ months of intense endurance training, indicating:
8-18 months indicating that each athlete has a finate maximal attainable level of O2 consumption.
SV during max exercise of untrained person: trained:
80-100 ml/beat 110-150 ml/beat bo
increased plasma volume mechanism 2: Exercise increases release of ___ and ___, hormones that cause ___ , which increases blood plasma. That increased fluid is kept in the vascular space by the ___ exerted by the proteins.
ADH, aldosterone reabsorption of H2O and Na+ in the kidneys oncotic pressure
aerobic training causes changes in mitochondrial function that improve muscle fibers' capacity to produce ____. The ability to use ___ and produce ___ via oxidation depends on the number and size of mitochondria. ___ increase with training. The magnitude of change depends on ___
ATP O2, ATP both training volume
in muscular activities that require near-max force production for relatively short periods of time, such as sprinting, much of the energy needs are met by the ___ system and the anaerobic breakdown of ___ (___). The trainability of these systems are the focus of the following sections
ATP-PCr muscle glycogen (glycolysis)
activities that emphasize maximal muscle force production (sprinting, weight lifting) rely most heavily on the ___ for energy
ATP-PCr system
effect of endurance training on submax BP: max BP:
BP reduced at given submax intensity SBP increases and DBP decreases at max exercise capacity
for the sedentary, middle aged adult, numerous health factors indicate that ___ should be the primary emphasis of training.
CV endurance
Both the total amount (absolute values) of ___ and the total number of ___ are typically elevated in highly trained athletes, though these values relative to total blood volume are ___ normal. This ensures what?
Hb, RBCs below ensures blood has more than ample O2-carrying capacity
How does a trained runner's La+ response differ from an untrained person's? What does this translate into?
In the trained state, one can exercise at a higher percentage of VO2max before lactate begins to accumulate in the blood. A must faster race pace
explain all the aspects that go into increasing stroke volume:
Increased contractility resulting from an increase in LV thickness and greater diastolic filling (frank-starling), coupled with the reduction in TPR, increases the ejection fraction in the trained heart. More blood enters the LV, and a greater percentage of what enters is forced out with each contraction, resulting in an increase in SV
Although the largest part of the increase in VO2max results from the increases in ___ and ___, and increase in ___ also plays a key role
Q, muscle blood flow a-v O2 difference
increases in VO2max depend on adaptations in ___ and ___. Why?
SVmax max (a-v)O2 diff HRmax either stays the same or decreases with training (due to age)
What did the study show that compared untrained men with VO2max values below 49 ml/kg/min to men with VO2max values above 62.5 ml/kg/min?
Those with high VO2max values were distinguished by having higher blood volumes, which contributed to higher SVs and Qs at max intensities. The higher blood volumes in the high VO2max group were most likely genetically determined.
the increase in capillary density is potentially one of the most important adaptations to aerobic training that causes the increase in ___. Why?
VO2max the diffusion of O2 from the capillary to the mitochondria is a major limiting factor of the maximal rate of O2 consumption by the muscle. Increasing capillary density facilitates this diffusion, thus maintaining an env't well suited to energy production and repeated muscle contractions.
What happened in the study involving the activity of SDH over 7 months of progressive swim training? What does this suggest?
While the rate of increases in VO2max slowed after the first 2 months of training, activity of SDH continued to increase throughout the entire training period suggests that training induced increases in VO2max might be limited more by the circulatory system's ability to transport O2 than by the muscles' oxidative potential.
How does the HR recovery period compare b/w trained and untrained people? What measurement has this been proposed for?
a more fit person recovers faster after a standardized rate of work than a less fit person indirect index of CR fitness
what is cardiorespiratory endurance?
ability to sustain prolonged, dynamic whole-body exercise using large muscle groups
Blood flow is directed to the ___ musculature and shunted away from areas that don't need high flow. Blood flow can increase to the more active fibers even within a specific muscle group.
active
The increase in LV muscle mass is in direct response to repeated exposure to in the increased ___ with RT
afterload
Changes in HR and SV in response to training have one common goal:
allow heart to pump max amount of oxygenated blood at lowest energy cost
What happens to Q when HR is too high?
allows very little time for ventricles to fill, SV may decrease
anaerobic training improves anaerobic ____; ___term, ___ intensity exercise capacity; tolerance for ___ imbalances; and, in some cases, muscle ___
anaerobic metabolism short, high acid-base strength
A trained athletes hematocrit can decrease to such an extent that the athlete appears to be ___ on the basis of relatively low concentration of RBCs and Hb ("___")
anemic pseudoanemia
One test used to determine submaximal endurance capacity is the ___ a person can maintain over a fixed period of time on a cycle ergometer. For running, the ___ or ___ a person can maintain during a set period of time would be a similar type of test
average peak absolute power output average peak speed/velocity
what's the best indicator of anaerobic capacity?
average power output
Why won't shifting more blood into the capillaries severely compromise venous return?
because endurance training also increases blood volume
what happens to type I fibers in response to aerobic training?
become larger (increase CSA)
The body's total ___ increases with endurance exercise, providing more blood to meet body's many blood flow needs during endurance activity.
blood volume
The wide range of of SV values for any given population is largely attributable to differences in ___
body size
The ability to sustain exercise at a higher percentage of VO2max is partly the result of an increase in the ability to ___, because race pace is directly related to the VO2 value at which ___
buffer La+ La+ begins to accumulate (OBLA)
how could a high aerobic endurance capacity benefit an athlete who performs bursts of activity (football player) and claims they only need anaerobic training?
burst-type activity may be performed many times during the game. The athlete could maintain the quality of each burst activity throughout the game and would still be relatively "fresh" (have less drop-off in performance, fewer feelings of fatigue) during the 4th quarter with a higher aerobic endurance capacity
one of the most important adaptations to aerobic training is an increase in the number of ___ surrounding each muscle fiber
capillaries
aerobic training improves ___ function and peripheral ___ and enhances the capacity of muscle fibers to generate greater amounts of ___
cardiac blood flow ATP
at one time, ___, aka "___" was viewed with concern because this was thought to reflect pathology (HTN). ____ is now recognized as a normal adaptation to chronic endurance training
cardiac hypertrophy "athlete's heart" training-induced cardiac hypertrophy
many people regard ___ as the most important component of physical fitness.
cardiorespiratory endurance
during a single bout of exercise, the body precisely adjusts its ___ and ___ function to meet oxygen demands of actively contracting muscle. When these systems are challenged repeatedly, as happens with regular exercise training, they adapt in ways that allow the body to improve ___ and overall ___
cardiovascular, respiratory VO2max, endurance performance
myoglobin transports O2 from the ___ to the ___
cell membranes, mitochondria
Data from a review support the hypothesis that both LV ___ and ___ increase with endurance training
chamber size wall thickness
two important oxidative enzymes: where are each of these found?
citrate synthase --> krebs cycle Succinate Dehydrogenase (SDH) --> ETC
HR recovery curve is useful tool for tracking a person's progress during training program, but because of the potential influence of other factors, it shouldn't be used to ___ people
compare
The increase in submaximal exercise capacity is related to ____.
competitive endurance performance
Submax endurance capacity is more closely related to actual ___ than VO2max and is likely determined by both ___ and the ___. With endurance training, submaximal endurance capacity ___
competitive endurance performance VO2max, LT
The decline in ___ and ___ associated with fatigue is particularly important. Why?
concentration, alertness the althete can become careless and more prone to serious injury, especially in contact sports
Increased ventricular muscle mass results in increased ___, in turn causing a lower ___
contractile force ESV
what's the "take home message" of HIIT?
cytochrome oxidase (COX) increases the same after hit versus traditional moderate-intensity endurance training.
Decreased ESV is facilitated by the ___ that occurs with training
decrease in peripheral resistance
the extent of endurance training needed varies considerably from one sport to the next and from one person to the next. it depends on the athlete's current ___ and the ___ demands of the chosen activity. However, adequate CV conditioning must be the ___ of any athletes general conditioning program
endurance capacity endurance foundation
One of the physiological benefits of decreasing blood viscosity:
enhances O2 delivery to active muscle mass
low endurance capacity leads to ___, even in activities that aren't aerobic. For any athlete, regardless of the sport or activity, ___ represents a major deterrent to optimal performance
fatigue fatigue
more blood entering the ventricle increases the stretch on the ventricular walls; by the ___, this results in an increased ___
frank-starling mechanism force of contraction
Having more capillaries allows for greater exchange of: (4) between the blood and contracting muscle fibers
gases, heat, nutrients, metabolic by-products
Both ___ and ___ factors influence VO2max values. The ___ factors probably establish the boundaries for the athlete, but ___ can push VO2max to the upper limit of these boundaries
genetic, environmental genetic endurance training
the finite range in maximal attainable level of O2 consumption is ___ determined but may potentially be influenced by training in early childhood during the development of the CV system
genetically
the ability to increase VO2max level is ___ limited. A person has a(n) ___ of VO2max values that seems to be predetermined by one's genetic make up, with that person's highest attainable VO2max somewhere in there.
genetically range
why does an elite athlete have such a high VO2max?
genetically blessed (higher genetically determined VO2max) and react to training better
one metabolic consequence of mitochondrial changes by aerobic training is ___
glycogen sparing
7 CV adaptations that occur in response to exercise training:
heart size HR SV Q blood flow BP blood volume
As max levels of exercise are achieved, ___, ___, ___, and ___ can all potentially limit the max ability to transport O2. Endurance training elicits numerous changes in the components of the ___ that enable it to function more effectively
heart size, blood flow BP blood volume O2 transport system
although the actual number of RBCs may increase with training, the ___ may decrease. How?
hematocrit plasma volume increases more than RBCs increase
what is HIIT?
high intensity interval training: time efficient way to induce many adaptations normally associated with endurance training
SV is substantially ___ at rest after an endurance training program than before program
higher
The turnover rate of RBCs may also be ___ with intense training
higher
The increase in RBC contributing to the overall increase in blood volume with training is a(n) ___ finding
inconsistent
what significance does an increased number of capillaries have in response to aerobic training?
increased capillary density slows down the blood around muscle fiber itself and allows myoglobin to pull more O2 from Hb. The increased myoglobin content also assists in this process. More myoglobin means more O2 is being utilized by the muscle fiber and mitochondria
What also changes in the LV in response to endurance training? What does this allow for?
increased myocardial wall thickness greater force of contraction
what is a decreased resting HR primarily due to?
increased parasympathetic drive over coming sympathetic activity in the heart
faster HR recovery post exercise is explained by:
increased parasympathetic tone --> responds more quickly after exercise and overtakes SNS
It's likely that the first phase of rapid plasma volume increase is the result of ___, which is noted within the first ___ of recovery from the first training bout. In the second phase, ____ is upregulated (turned on) by repeated exercise, and new ___ are formed.
increased plasma albumin, hour protein synthesis proteins
3 adaptations to endurance exercise that increase EDV (preload)
increased plasma volume increased ventricular filling rate and venous return increased LV cardiac muscle
Two factors that can account for the increase in max ventilation following training:
increased tidal volume increased respiratory frequency at max exercise
pulmonary diffusion at max intensity ___, especially to ___ regions of the lung that are not normally perfused
increases upper
moderate daily exercise ___ oxidative enzyme activity. What does this cause?
increases causes oxidative capacity of muscle to increase as well
As plasma protein concentration increases, oncotic pressure ___. What does this cause?
increases fluid is reabsorbed from the interstitial fluid into the blood vessels
Endurance training ___ total blood volume, and this effect is ___ at higher training intensities. The effect also occurs ___.
increases larger rapidly
How does VO2max change with endurance training? What does this allow for?
increases by 15-20% after a 20-week training program. allows individual to perform endurance activities at higher intensity, improving their performance potential. Increased maximal endurance capacity
what happens to myoglobin content in response to aerobic training? What does this result in?
increases by 75-80% supports a muscle's increased capacity for oxidative metabolism after training
How does max Q respond to endurance training: why?
increases considerably due to increase in SVmax
The increase in number and size of muscle fiber mitochondria is further enhanced by an increase in ___. The oxidative breakdown of fuels and the ultimate production of ATP depend on ___, the special proteins that catalyze the breakdown of nutrients to form ATP. How does aerobic train affect these?
mitochondrial capacity mitochondrial oxidative enzymes their activity increases in response to training
aerobic training increases both the number of capillaries per ___ and the number of capillaries for a given ___ of muscle. These changes improve blood ___ through muscles, enhancing diffusion of ___, ___, ___ and ___ between the blood and muscle fibers
muscle fiber cross-sectional area perfusion O2, CO2, nutrients, metabolic byproducts
as an adaptation to the increased work demand, cardiac ___ and ventricular ___ increase with training
muscle mass volume
the changes occuring in the ___, combined with adaptations in the ___, enhance the capacity of oxidative metabolism and improve endurance performance
muscles oxygen transport system
studies suggest the major value of training bouts that last only a few seconds (sprints) is the development of ____. What does this enable the athlete to do?
muscular strength perform given task with less effort, which reduces risk of fatigue.
To permit increased blood flow, ___ capillaries develop in trained muscles. This allows the blood flowing into skeletal muscle from arterioles to more fully ____ the active fibers. This increase in capillaries usually is expressed as an increase in the number of capillaries per muscle fiber, or the ___
new perfuse capillary-to-fiber ratio
does chronic exposure to increased BP during RT elevate resting BP?
no, may lower resting BP
aerobic training increases both the ___ and ___ of muscle fiber mitochondria, providing the muscle with an increased capacity for ___
number, size oxidative metabolism
increased plasma volume mechanism 1: Plasma proteins are the main driver of ____ in the vasculature..
oncotic pressure
In addition to new capillarization, existing capillaries in trained muscles can be recruited to ___ to flow which also increases blood flow to muscle fibers.
open
in all tissues, including muscle, not all capillaries are ___ at any given time
open
the increased extraction results in part from an increase in ___ of active muscle
oxidative capacity
___, the highest mechanical power achieved during the first 5-10s, is considered an index of anaerobic power
peak power
The increase in LV dimensions with endur. training is largely attributable to a training-induced increase in ___ that increases ventricular ___ (increased ___)
plasma volume EDV (preload)
With endurance training, the internal dimensions of the LV increase, mostly in response to an increase in ___, and secondarily to an increase in ___
plasma volume ventricular filling
The increases in ___ and ___ increase the ___ at the end of diastole. This effect of endurance training on the LV is often called a(n) ___
plasma volume diastolic filling time ventricular chamber size volume loading effect
Enhanced glycogen sparing with endurance training most likely improves the ability to do what?
sustain a higher exercise intensity (maintaining faster race pace)
why does pulmonary ventilation increase at max exercise intensities?
pulmonary blood flow increases following training, particularly flow to upper regions of lungs when a person's standing or standing. This increases lung perfusion. More blood is brought into the lungs for gas exchange, and at the same time ventilation increases so that more air is brought into the lungs. This means that more alveoli will be involved in pulmonary diffusion. The net result is that pulmonary diffusion increases.
However, some evidence suggests that at some point in a highly trained person's adaptation, what happens to the pulmonary system's capacity for O2 transport? What does this result in? What does this result from?
pulmonary system's capacity for O2 transport may not be able to meet the demands of the limbs and the CV system. Results in exercise-induced arterial hypoxemia in which arterial O2 saturation decreases below 96%. Results from large right heart cardiac output directed to the lung during exercise and a consequent decrease in time the blood spends in the lung.
to support increases in VO2max, there's an increase in ___ during maximal effort following training as both ___ and ___ increase
pulmonary ventilation tidal volume, respiratory rate
if there a decrease in RER (increased FFA utilization) what does this mean about pyruvate production? why?
pyruvate production would decrease. Low RER and increased FFA utilization suggests the athlete is working at a lower intensity which would recruit less type II fibers than a higher work rate. Because type II fibers aren't being used as much, less La+ is being produced. Also, FFAs don't go through glycolysis so less pyruvate will be produced.
A more effective ___ of Q also can increase blood flow to the active muscles.
redistribution
above the LT, the lower lactate of the trained person at a given work rate is likely attributable to a combo of ____ and ___. as athletes become better trained, their post-exercise blood lactate concentrations are ___ for a given work rate
reduced lactate production increased lactate clearance lower
The increased ratio of plasma to cells resulting from a greater increase in the fluid portion does what to the blood's viscosity? What does this aid?
reduces it, makes it thinner may aid smooth flow of blood through BVs, particularly through smaller vessels like capillaries
adaptations to HIIT mirror those associated with more traditional aerobic training. HIIT appears to stimulate some of the same molecular signaling pathways that regulate skeletal muscle ___ in response to endurance training, including ___ and changes in the capacity for ___ and ___
remodeling mitochondrial biogenesis carbohydrate and fat transport and oxidation
no matter how proficient the CV system is at supplying blood to exercising muscle, endurance would be hindered if the ___ system were not able to bring enough O2 to fully oxygenate RBCs
respiratory
the ___ to training is also genetically determined. There will be ___ and ___ among groups of people who participate in identical training programs
response high responders, low responders
How does aerobic training affect HR?
rest: decreases markedly (~1 bpm per wk of training) submax: decreases for same given absolute intensity max: no significant change, decreases with age
pulmonary diffusion adaptations to aerobic exercise at rest: during submax: max:
rest: unaltered submax: unaltered max: increases
how do resting and submax VO2 change with aerobic training?
resting: unchanged submax at given intensity: either unchanged or slightly reduced.
In summary, the respiratory system is quite adept at bringing adequate O2 into the body. For this reason, the respiratory system ___ limits endurance performance. The major training adaptations noted in the respiratory system are apparent mainly during ___, when all systems are being ___ stressed
seldom maximal exercise maximally
What does HIIT result in?
similar improvements to traditional endurance-type exercise of moderate-to-vigorous intensity
what is glycogen sparing?
slower rate of utilization of muscle glycogen and enhanced reliance on fat as a fuel source at a given exercise intensity.
Even minor fatigue can hinder the athlete's total performance: -muscular ___ is decreased -reaction and movement times are ___ -agility and neuromuscular coordination are ___ -whole-body movement speed is ___ -concentration and alertness are ___
strength prolonged decreased slowed reduced