Cardiorespiratory Adaptations
to Training
Chapter 13
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Cardiorespiratory
endurance
 refers
to your
body’s ability to
sustain prolonged,
rhythmical
exercise.
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Cardiorespiratory Endurance
 Highly
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related to aerobic development.
Cardiorespiratory Endurance
 VO2MAX
is the best indicator of
cardiorespiratory endurance.
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VO2MAX
 Absolute
and relative measures.
– absolute = l . min-1
– relative = ml . kg-1 . min-1
 VO2
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= SV x HR x a-vO2diff
Cardiovascular Response
 Left
ventricle undergoes the most change in
response to endurance training.
 internal
dimensions of the left ventricle
increase.
– (mostly in response to an increase in
ventricular filling)
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Cardiovascular Response
 left
ventricle wall
thickness also
increases, increasing
the strength potential
of that chamber’s
contractions.
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Left
Ventricle
Cardiovascular Response
 Following
endurance training, stroke
volume increases during rest, submaximal
levels of exercise, and maximal exertion.
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Cardiovascular Response
A
major factor leading to the stroke volume
increase is an increased end-diastolic
volume, probably caused by an increase in
blood plasma.
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Cardiovascular Response
 Another
major factor is increased left
ventricular contractility.
 This is caused by hypertrophy of the cardiac
muscle and increased elastic recoil, which
results from increased stretching of the
chamber with more diastolic filling.
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Heart Rate Adaptations:
A
person’s
submaximal HR
decreases
proportionally with the
amount of training
completed.
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Heart Rate Adaptations:
 Maximal
HR either remains unchanged or
decreases slightly with training.
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Heart Rate Adaptations:
 When
a decrease occurs, it is probably to
allow for optimum stroke volume to
maximize cardiac output.
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Heart Rate Adaptations:
 The
HR recovery period decreases with
increased endurance, making this value well
suited to tracking an individual’s progress
with training.
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Heart Rate Adaptations:
 However,
this is not useful for comparing
fitness levels of different people.
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Heart Rate Adaptations:
 Resistance
training can also lead to reduced
heart rates; however, these decreases are not
as reliable or as large as those seen with
endurance training.
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Cardiac Output Adaptations:
 Cardiac
output at rest or during submaximal
levels of exercise remains unchanged or
decreases slightly after training.
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Cardiac Output Adaptations:
 Cardiac
output at maximal levels of
exercise increases considerably.
 This
is largely the result of the submaximal
increase in maximal stroke volume.
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Blood Distribution Adaptations
Blood
flow to muscles
is increased by
endurance training.
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Blood Distribution Adaptations
 Increased
blood flow results from four
factors:
–
–
–
–
Increased capillarization.
Greater opening of existing capillaries.
More effective blood redistribution.
Increased blood volume.
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Blood Pressure Adaptations:
 Resting
blood pressure is generally reduced
by endurance training in those with
borderline or moderate hypertension.
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Blood Pressure Adaptations:
 Endurance
training has little or no effect on
blood pressure during standardized
submaximal or maximal exercise.
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Blood Volume Adaptations:
 Blood
volume increases as a result of
endurance training.
 The
increase is primarily caused by an
increase in blood plasma.
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Blood Volume Adaptations:
 RBC
count can increase, but the gain in
plasma is typically much higher, resulting in
a relatively greater fluid portion of the
blood.
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Blood Volume Adaptations:
 Increased
plasma volume causes decreased
blood viscosity, which can improve
circulation and oxygen availability.
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Blood Volume Adaptations:
 The
training-induced increase in plasma
volume, and its impact on stroke volume
and VO2MAX, make it one of the most
significant training effects.
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Pulmonary Adaptations:
 Most
static lung volumes remain essentially
unchanged after training.
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Pulmonary Adaptations:
 Tidal
volume, though unchanged at rest and
during submaximal exercise, increases with
maximal exertion.
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Pulmonary Adaptations:
 Respiratory
rate remains steady at rest, can
decrease slightly with submaximal exercise,
but increases considerably with maximal
exercise after training.
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Pulmonary Adaptations:
 The
combined effect of increased tidal
volume and respiration rate is an increase in
pulmonary ventilation at maximal effort
following training.
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Pulmonary Adaptations:
 Pulmonary
diffusion at maximal work rates
increases, probably because of increased
ventilation and increased lung perfusion.
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Pulmonary Adaptations:
 a-vO2diff
increases with training, reflecting
an increased oxygen extraction by the
tissues and more effective blood
distribution.
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Acid-Base Balance
Adaptations:
 Lactate
threshold increases with endurance
training, which allows you to perform at
higher rates of work and levels of oxygen
consumption without increasing your blood
lactate above resting levels.
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Acid-Base Balance
Adaptations:
 Maximal
blood lactate levels can be
increased slightly.
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Oxygen Consumption
Adaptations:
 The
respiratory exchange ratio decreases at
submaximal work rates, indicating a greater
utilization of free fatty acids.
 It
increases at maximal effort.
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Oxygen Consumption
Adaptations:
 Oxygen
consumption can be increased
slightly at rest.
 It
can be decreased slightly or remain
unaltered during submaximal exercise.
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Oxygen Consumption
Adaptations:
 VO2MAX
increases substantially following
training, but the amount of increase possible
is limited in each individual.
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Oxygen Consumption
Adaptations:
 The
major limiting factor appears to be
oxygen delivery to the active muscles.
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Oxygen Consumption
Adaptations:
 Although
VO2MAX has an upper limit,
endurance performance can continue to
improve for years with continued training.
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Oxygen Consumption
Adaptations:
 An
individual’s genetic makeup
predetermines a range for his/her VO2MAX,
accounting for 25% to 50% of the variance
in VO2MAX values.
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Oxygen Consumption
Adaptations:
 Heredity
also largely explains individual
variations in response to identical training
programs.
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Oxygen Consumption
Adaptations:
 Age-related
decreases in aerobic capacity
might partly result from decreased activity.
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Oxygen Consumption
Adaptations:
 Highly
conditioned female endurance
athletes have VO2MAX values only about
10% lower than those of highly conditioned
male endurance athletes.
– Body size
– Hemoglobin content
– Percent lean mass
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Oxygen Consumption
Adaptations:
 To
maximize cardiorespiratory gains,
training should be specific to the type of
activity the exerciser usually performs.
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Oxygen Consumption
Adaptations:
 Resistance
training in combination with
endurance training does not appear to
restrict improvement in aerobic capacity
and may increase short-term endurance.
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Oxygen Consumption
Adaptations:
 All
exercisers can benefit from maximizing
their endurance.
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Determining Exercise Intensity
For basic health and fitness:
 40-45%
of heart rate or VO2 reserve, or 5064% of heart rate max
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Determining Exercise Intensity
For optimal health and fitness:
 50-85%
of heart rate or VO2 reserve, or 6590% of heart rate max
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Determining Exercise Intensity
 Heart
rate max
Calculated by
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208 – 0.7(age)
Determining Exercise Intensity
 Heart
Rate Reserve
Heart rate max – resting heart rate
 VO2
Reserve
VO2max – resting VO2
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Determining Exercise Intensity
Sample calculation based on HRres
 Find HRmax
 208-0.7(age)
208-0.7(20) = 194
 HRmax – HRrest
194-70 = 127
 HRR times %
127 x .50 = 63.5
– 50-85%
 Add
HRrest
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127 x .85 = 108
64 + 70 = 134
108 + 70 = 178
Determining Exercise Intensity
Sample calculation based on VO2res
 Measure or estimate VO2 max
 Find VO2 res
– VO2max – VO2 rest
 VO2res
times %
– 50 and 85%
 Add
VO2 rest
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45 – 3.5 = 41.5
41.5 x .50 = 20.75
41.5 x .85 = 35.28
20.75 + 3.5 = 24.25
41.5 + 3.5 = 45
Determining Exercise Intensity
 Based
on HR max
 208 – 0.7(age)
 Times 65-90%

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208-0.7(20) = 194
194 x .65 = 126
194 x .90 = 175