The document presents an overview of aerobic exercise, including physiological responses, exercise testing, and program development. It discusses the cardiovascular and respiratory responses to exercise, highlights various testing methods for aerobic capacity, and outlines factors such as intensity, duration, frequency, and the principles of overload and specificity. Additionally, it details the normal and abnormal responses to acute aerobic exercise, as well as the long-term physiological changes that occur with training.

1. Aerobic Exercise
Presented by
Dr. Anaz A (MPT- MSS)

2. Topics
• Physiological response to aerobic exercise
• Examination and evaluation of aerobic capacity
• Exercise Testing
• Determinants of an Exercise Program,
• The Exercise Program,
• Normal and abnormal response to acute aerobic exercise,
• Physiological changes that occur with training,
• Application of Principles of an Aerobic conditioning program
for patients – types and phases of aerobic training. -
SEMINAR

3. Physiological response to aerobic
exercise
• why?
• To manage increased energy requirement
• Rapid circulatory adjustment to meet the increased need for
oxygen and nutrients
• To remove the end products of metabolism (c02, lactic acid)
• To dissipate excess heat
1. Cardiovascular response
1. Exercise Pressor Response
2. Cardiac Effects
3. Peripheral Effects

4. 2. Respiratory Response to Exercise
3. Responses Providing Additional Oxygen to Muscle

5. Cardiovascular response
1. Exercise Pressor Response
1. Generalized peripheral vasoconstriction in non exercising
muscles
2. increased myocardial contractility  increased heart rate
increased systolic blood pressure.
“This results in a marked increase and redistribution of the
cardiac output.”

6. 2. Cardiac effects
• The frequency of sinoatrial node depolarization  HR
• vagal stimuli and SNS stimulation
3. Peripheral effects
• Vasoconstriction causing shunting of blood from kidneys, liver,
spleen to the working muscles
• resistance in the working muscle arterial vascular bed
• The veins of the working and nonworking muscles remain
constricted
• Increased CO
• Increased SBP.

7. Respiratory response
• Changes occur even before the exercise
• Gas exchange (O2, CO2) increases across the alveolar-capillary
membrane by the first or second breath
More O2 extracted from arterial blood ↑ PC02
increased stimulation of receptors
RR ↑
Minute ventilation ↑
TV ↑

8. Responses Providing Additional Oxygen
to Muscle
• Increased Blood Flow
• Increased Oxygen Extraction
• ↓ tissue PO2  unloading/extraction from Hb will be more
• ↑ CO2  acidotic  increase in temp  unloading/extraction
from Hb

9. Exercise testing
V02 max
• It is also called as Maximum oxygen consumption, max O2
uptake, peak O2 uptake or aerobic capacity.
• is the maximum capacity of an individual’s body to transport
and use oxygen during incremental exercise , which reflects
the physical fitness of the individual
Its expressed as VO2 max = ………. Litre of O2/ min
=………...ml of O2/kg body wt/min
• Types
1. Maximal exercise testing
2. Submaximal exercise testing

10. 1. Maximal graded exercise testing
• Mainly used for research purposes
• Maximal graded exercise testing total test time is 8 – 12
minutes
• Constantly monitored under ECG
• Requires analysis of expired gas
• Thus costly and time-consuming
• eg : Bruce protocol
2. Submaximal graded exercise testing
1. Bicycle Ergometer Test
1. YMCA protocol
2. Treadmill test
3. Step test
4. Field test
1. Cooper 12 minute test
2. 1 mile walk test

11. Treadmill test
• Developed for assessing vo2 max in low risk individuals
• It involves beginning with a comfortable pace between 2.0-
4.5mph at 0% grade for 2-4 minute (warmup), designed to ↑
HR within 50%-75% of age predicted (220-age) maximum HR.
• Followed by 4 minutes at 5% grade at the same self selected
walking speed.
• HR is measured at the end of minute stage and VO2 max is
estimated using the following equation

13. Bruce Protocol (maximal test)
• The Bruce protocol involves getting on a treadmill and
increasing speed and incline every three minutes (in stages).
• The test stops when you've hit 85% of your maximum heart
rate, your heart rate exceeds 115 beats per minute for two
stages, or it is deemed that the test should no longer
continue.

14. • T stands for total time on the treadmill and is measured as a
fraction of a minute (a test time of 10 minutes 15 seconds
would be written as T=10.25); and this formula changes based
on sex
Men: 14.8 - (1.379 x T) + (0.451 x T²) - (0.012 x T³) = VO2 max
Women: 4.38 x T - 3.9 = VO2 max

16. Queens college step test
• Requires 16.25-inch step
• Individuals step up and down to a 4-count rhythm
• A metronome is used to maintain the stepping beat
• For females 3 minutes rate of 22 steps per minute
(88beats/minute)
• For males 24 steps per minute (96beats/minute)
• At the end of 3 minutes, a recovery 15-second pulse is
measured. Then converted to bpm by multiplying by 4

17. 6-minute walk test
• The distance covered over a time of 6 minutes is used as
the outcome by which to compare changes in
performance capacity.
• The patient is permitted to slow down, to stop, and rest if
necessary
• He/she can lean against the wall
Interpretation
• An increase in the distance walked indicates
improvement in basic mobility
• Post training a difference of at least 45m should be
observed for the 6 minutes walk test to be sure that
a “real” change in the patient’s condition.

18. Determinants of an exercise
programme
• INTENSITY
• Determination of the appropriate intensity of exercise to use
is based on the overload principle and the specificity
principle
Overload Principle
• Overload is stress on an organism that is greater than that
regularly encountered during everyday life.
• To improve cardiovascular and muscular endurance, an
overload must be applied to these systems
• The exercise load (overload) must be above the training
stimulus threshold
• 70% of max HR is a minimal-level stimulus for eliciting a
conditioning response in healthy young individuals.

19. • Maximum HR = 220 – age
• Eg age is 20
• Max HR = 220 – 20
• = 200
Specificity principle
• The specificity principle as related to the specificity of training
refers to adaptations in metabolic and physiological systems
depending on the demand imposed
• There is no overlap when training for strength–power
activities and training for endurance activities

20. Duration
• A 20- to 30-minute session is generally optimal at 60% to 70%
maximum heart rate.
• When the intensity is below the heart rate threshold, a 45-
minute continuous exercise period may provide the
appropriate overload
• Frequency
• there is no clear-cut information provided on the most
effective frequency of exercise for adaptation to occur
• Frequency may be a less important factor than intensity or
duration in exercise training
• American Heart Association – 30 mnts moderate intensity
most if not all days of the week. (Centers for Disease Control
(CDC) supports these recommendations)

21. • American College of Sports Medicine – 3-5 Days a week at
65% - 90% max HR
Mode
• The important factor is that the exercise involves large muscle
groups that are activated in a rhythmic, aerobic nature.
Reversibility Principle
• After only 2 weeks of detraining, significant reductions in work
capacity can be measured
• The frequency or duration of physical activity required to
maintain a certain level of aerobic fitness is less than that
required to improve it.

22. Exercise programme
• There are three components of the exercise program:
I. A warmup period,
II. The aerobic exercise period,
III. A cooldown period

23. WARM-UP PERIOD
The purpose of the warm-up period is to enhance the numerous
adjustments that must take place before physical activity.
Physiological Responses
• ↑ in temp  efficiency of muscle contraction
• ↑ need for O2 to meet the energy demands
• Dilation of vessels
• ↑ venous return
Purpose
• Decreases susceptibility to injury
• ↓The occurrence of ischemic electrocardiographic (ECG)
changes and arrhythmias.

24. AEROBIC EXERCISE PERIOD
• conditioning part of the exercise program
• four methods of training that challenge the aerobic system:
continuous, interval (work relief), circuit, and circuit interval.
1. Continuous Training
• A submaximum energy requirement, sustained throughout
the training period, is imposed.
• Training 20-60 minutes
• continuous training is the most effective way to improve
endurance.
2. Interval Training
• the work or exercise is followed by a properly prescribed relief
or rest interval

25. • The relief interval is either a rest relief (passive recovery) or a
work relief (active recovery);
• its duration ranges from a few seconds to several minutes
3. Circuit Training
• Circuit training employs a series of exercise activities.
• At the end of the last activity, the individual starts from the
beginning and again moves through the series.
• The series of activities is repeated several times

26. (Video)

27. 4. Circuit-Interval Training
• Combining circuit and interval training is effective because of
the interaction of aerobic and anaerobic production of ATP

28. COOL-DOWN PERIOD
Purpose
• Prevent pooling of the blood in the extremities by continuing
to use the muscles to maintain venous return
• Prevent fainting by increasing the return of blood to the heart
and brain as cardiac output and venous return decreases
• Prevent myocardial ischemia, arrhythmias
Guidelines
• The period should last 5 to 10 minutes.

29. Normal and abnormal response
to acute aerobic exercise
Normal response to acute aerobic exercise
1. Heart rate (HR)
• Linear relationship between intensity of exercise and HR
• Intensity of exercise ∝ HR
2. Stroke volume (SV)
• Amount of blood pumped out from left ventricle per
heartbeat
• mL per beat
• Intensity of exercise ∝ SV (upto 50% of aerobic capacity),
after that slows down

30. 3. Cardiac output (Q)
• Amount of blood ejected from ventricle per minute (L per minute)
• Q = HR x SV
• Intensity of exercise ↑ ∝ Q
4. Arterial-venous oxygen difference (a-vo2 diff)
• Amount of O2 extracted by the tissues from the blood represents
the difference between arterial blood oxygen content and venous
blood oxygen content
• ↓ O2 content in venous blood
• Intensity of exercise ↑ ∝ a-vo2 diff
5. Blood flow
• At rest 15%-20% of CO goes to muscle
• During workout 80%-85% of CO goes to muscle
• But during intense exercise  body heat ↑  blood flow ↑ to skin
to conduct body heat out

31. 6. Blood pressure (BP)
• SBP and DBP respond differently to exercise
• Workload ↑ ∝ SBP ↑
• But DBP changes little and changes of <15mm Hg from resting
value are considered norma
• Both SBP and DBP are higher in UL exercise ( because of
increased resistance, small muscle mass and vasculature)
7. Pulmonary ventilation
Workload ↑ ∝ RR and depth of breathing

32. Abnormal responses to acute aerobic exercise
• The failure of HR to rise to increase in intensity
• Failure of SBP to rise / decrease ≥ 20mmHg

33. Physiological changes that occur
with training
1. Cardiovascular Changes
At rest
• ↓ in resting pulse rate
• ↓ BP
• ↑ blood volume, Hb
During exercise
• ↓ in resting pulse rate
• ↑ CO
• Increased extraction of O2
• Decreased blood flow per Kg

34. 2. Respiratory Changes
At rest
• ↑ lung volume
• Larger diffusion capacities
During exercise
• Larger diffusion capacities
• Minute ventilation ↑
• Ventilatory efficiency ↑

35. 3. Metabolic Changes
At rest
• Muscle hyper trophy, capillary density ↑
• number and size of mitochondria ↑
• muscle myoglobin concentration ↑
During exercise
• Blood lactate level ↓
• Less reliance on phosphocreatine
4. Other changes
• Body fat ↓
• Blood cholesterol ↓
• Heat acclimatization ↑
• Strength of bones, ligaments, tendons ↑

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