Download Q = HR x SV

Optimizing heart rate during
exericise
Dr. Aashish Contractor
HOD: Preventive Cardiology and Rehab, Asian Heart Inst.
Medical Director, Standard Chartered Mumbai Marathon
What is Exercise Physiology?
Definitions
• Physiology: is a branch of biological
•
science concerned with the function of
organisms and their parts.
Exercise physiology is a branch of
physiology that deals with the
functioning of the body during exercise.
Heart Anatomy
Cardiac Output
The amount of blood pumped by the heart
each minute
•
•
Product of heart rate and stroke volume
Q = HR x SV

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
Heart rate = number of beats per minute
Stroke volume = amount of blood ejected in each
beat
75 bpm x 70 mls/ beat = 5000 mls or 5
liters/min
Transition From Rest  Exercise
and Exercise  Recovery
• Rapid increase in HR, SV, cardiac
•
•
output
Plateau in submaximal (below lactate
threshold) exercise
Recovery depends on:

Duration and intensity of exercise

Training state of subject
Cardiovascular Response to
Endurance Training
• Maximum cardiac output increases
• Maximum stroke volume increases
• Maximum heart rate does not change
Lactate Threshold
Cardiovascular Conditioning
FITT

Frequency

Intensity

Type

Time
Exercise Programming
Components
Cardiovascular
• Frequency- 3-5 days/week
• Intensity- 55/65% - 90% HR max
•
•
40/50% - 85% VO2R or HRR
Duration- 20-60 min of continuous or
intermittent (minimum 10 min bouts)
Mode- uses large muscle groups,
maintained continuously, and rhythmical
in nature
Intensity
•
•
•
Intensity refers to how hard the body is
working during exercise.
Needs to be sufficient to overload the body in
order to achieve a training effect.
Common ways for deciding the intensity
would be by using



Age predicted formula
Karvonen formula
Functional capacity (MET system)
•
Age predicted formula :
HRmax = 220 – Age
•
Karvonen method : Using Heart Rate
Reserve (HRR) to calculate intensity
HRR = MHR – RHR
Target HR intensity = Target % HRR +
RHR
Guidelines for choosing intensity
•
To experience benefits of cardiovascular exercise
one must work at an intensity of

50 % - 85 % of VO2max (MET system)

50 % - 85 % of HRR method

60 % - 90 % of HRmax
Monitoring Intensity
•
Heart rate method
•
RPE scale
•
Talk test method
Heart Rate
Depending on the person’s level of fitness,
calculate the Target heart rate intensity
range by using the Age predicted formula
or the Karvonen method and accordingly
ask the client to maintain his exercise
intensity in that range.
Rate of Perceived Exertion
(RPE)
•
Indicates a quantitative
feeling of fatigue
•
Used to regulate
exercise intensity
Borg RPE Scale
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6
7
8
9
10
11
12
13
14
14
16
17
18
19
20
very , very light
very light
fairly light
somewhat hard
hard
very hard
very, very hard
Talk Test
•
This simple test indicates if an individual is
working at an appropriate intensity by
whether or not he or she can converse
while exercising. Breathing should be
rhythmical and comfortable. If the person
is gasping for breath between words then
exercise intensity is too high.