Transcript Aerobic Exercises

Dpt 5th semester
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Cardiovascular Changes
Respiratory Changes
Metabolic Changes
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Changes at Rest
A reduction in the resting pulse rate occurs in some
individuals because of a decrease in sympathetic drive,
 decreasing levels of norepinephrine and epinephrine
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increase in parasympathetic (vagal) tone secondary to
decreased sympathetic tone
A decrease in blood pressure occurs in some individuals
with a decrease in peripheral vascular resistance.
 An increase in blood volume and hemoglobin may occur
 This facilitates the oxygen delivery capacity of the system.
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Changes During Exercise
A reduction in the pulse rate occurs in some individuals
Increased stroke volume may occur because of an increase in
myocardial contractility and an increase in ventricular volume.
 Increased cardiac output may occur as a result of the
 increased stroke volume that occurs with maximum exercise but
not with submaximum exercise.
 Increased extraction of oxygen by the working muscle occurs in
some individuals because of
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 enzymatic and biochemical changes in the muscle,
 as well as increased maximum oxygen uptake (VO2 max).
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Greater VO2 max results in a greater work capacity.
The increased cardiacoutput increases the delivery of oxygen to
the working
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The increased ability of the muscle to extract
oxygen from the blood increases the
utilization of the available oxygen.
Decreased myocardial oxygen consumption
(pulse rate times systolic blood pressure)
modest decrease in blood pressure.
1.Changes at Rest
 Larger lung volumes develop because of improved
pulmonary function
 Larger diffusion capacities develop because of larger
lung volumes and greater alveolar-capillary surface
area.
2. Changes During Exercise
 Larger diffusion capacities occur for the same
reasons as those listed previously; the maximum
capacity of venti-lation is unchanged.
 maximum diffusion capacity is unchanged.
 The maximal minute ventilation is increased.
 Ventilatory efficiency is increased.
Changes at Rest
Muscle hypertrophy and increased capillary density occurs.
 The number and size of mitochondria are increased,
 increasing the capacity to generate ATP aerobically.
 The muscle myoglobin concentration increases,
 increasing the rate of oxygen transport and possibly the rate of
oxygen diffusion to the mitochondria.
Changes During Exercise
 decreased rate of depletion of muscle glycogen at submaximum
work levels may occur. Another term for this phenomenon is
glycogen sparing.
 It is due to an increased capacity to mobilize and oxidize fat and
increased fat-mobilizing and fat-metabolizing enzymes.
 Lower blood lactate levels at submaximum work may occur.
 Less reliance on phosphocreatine (PC) and ATP in skeletal
muscle.
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3.
Inpatient Phase (Phase I)
Outpatient Phase (Phase II)
Outpatient Program (Phase III)
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The inpatient phase start in the hospital following stabilization of the
patient’s cardiovascular status after MI or coronary bypass surgery.
length of hospital care has decreased
time may be limited to 3 to 5 days.
Purpose
Initiate risk factor education and address future modification of certain
behaviors, such as eating habits and smoking.
Initiate self-care activities and progress from sitting to standing to
minimize deconditioning (1 to 3 days postevent).
Provide an orthostatic challenge to the cardiovascular system (3 to 5
days postevent).
This is usually accom-plished by supervised ambulation.
Ambulation is usually monitored electrocardiographically,
And manually monitoring the heart rate, ventilation rate, and blood
pressure.
Prepare patients and family for continued rehabilitation and for life at
home after a cardiac event.
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phase started upon discharge from the hospital or, depending on the
severity of the diagnosis, 6 to 8 weeks later.
This delay allows time for the myocardium to heal as well as to monitor
the patient’s response to a new medical regimen.
Participants are monitored to determine heart rate and rhythm
responses; blood pressure is recor-ded at rest and during exercise;
and ventilation responses
Purpose
Increase the person’s exercise capacity in a safe, pro-gressive manner
so adaptive cardiovascular and mus-cular changes occur.
The early part of the program referred to by some as “low-level”
exercise training.
Enhance cardiac functions and reduce the cardiac cost of work.
This may help eliminate or delay symptoms such as angina and STsegment changes in the patient with coronary heart disease.
Determine the effect of medications on increasing levels of activity.
Relieve anxiety and depression.
Progress the patient to an independent exercise program.
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A symptom-limited exercise stress test is
performed 6 to 12 weeks after hospital
discharge (or as early as 2 to 4 weeks
following discharge).
The exercise program is predominantly
aerobic
Gen-erally, for patients with functional
capacities greater than 5METs,
the exercise prescription is based on the
results ofthe symptom-limited test.
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Intensity.
may be as low as 40% to 60% of the maximum heart rate or 40%
to 70% of the functional capacity defined in METs.
The starting intensity is dictated by the severity of the diagnosis
in concert with the individual’s age and prior fitness level.
Duration.
The duration of the exercise session may be limited to 10 to 15
minutes at the start, progressing to 30 to 60 minutes as the
patient’s status improves. Each session usually includes 8- to 10minute warm-up and cool-down periods.
Frequency.
three times per week.
Mode.
continuous, using large muscle groups, such as stationary biking or
walking.
These activities allow ECG monitoring via telemetry.
Method.
Circuit-interval exercise is a common method used with the patient during phase
II. The patient can exercise on each modality at a defined workload, compared
with exercising continuously on a bicycle or treadmill.
 Exercise at a higher intensity—fitness may improve within a shorter period of
time.
 Weight training
 . Low-level weight training may be initiat-ed during the outpatient program,
provided the individualhas undergone a symptom-limited stress test.
 Resistive exercises should not produce ischemic symptoms associated with an
increase in heart rate and systolic blood pres-sure. Therefore, heart rate and
blood pressure should be monitored periodically throughout the exercise session.
 Starting weight may be calculated using 40% of 1-RM .
 Progression.
 Progression of the workload occurs when there have been three consecutive
sessions (every-other-day sessions) during which the peak heart rate is below the
target heart rate
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phase of cardiac rehabilitation continued in a
hospital or community setting.
 Heart rate and rhythm are no longer monitored
via telemetry.
 Participants are reminded to monitor their own
pulse rate, and a supervisory person is available
to monitor blood pressure.
 Purpose
 The purpose of the program is to continue to
improve or maintain fitness levels achieved
during the phase I program.
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Guidelines
Recreational activities. Swimming, which
incorporates both arms and legs.
 However, there is a decreased awareness of
ischemic symptoms while swimming, especially
when the skill level is poor.
 Outdoor hiking, which is excellent if on level
terrain.
 Activities at 8 METs.
 Jogging approximately 5 miles per hour
 Cycling approximately 12 miles per hour
 Vigorous down-hill skiing.
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Special Considerations
Arm exercises elicit different responses than leg exercises.
Mechanical efficiency based on the ratio between output
of external work and caloric expenditure is lower than
with leg exercises.
Oxygen uptake at a given external workload is significantly higher for arm exercises than for leg exercises.
Myocardial efficiency is lower with leg exercises than
with arm exercises.
Myocardial oxygen consumption (heart rate systolic
blood pressure) is higher with arm exercises than with
leg exercises
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Increased myocardial aerobic work capacity.
Increased maximum aerobic or functional capacity
Increased stroke volume following high-intensity
train-ing 6 to 12 months into the training program.
Decreased myocardial demand for oxygen.
Increased myocardial supply by the decreased heart
rate and prolongation of diastole.
Increased tolerance to a given physical workload
before angina occurs.
lower heart rate at each submaximum workload and
therefore a greater heart rate reserve.
Improved psychological orientation and, over time, an
impact on depression scores, scores for hysteria