Transcript The cardiovascular system and its response to exercise

The cardiovascular
system and its response
to exercise
Aims of the seminar
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To recap on the previous session (the
structure and function of the
cardiovascular system.
To identify the changes in heart rate
during exercise.
To identify and understand the changes in
the respiratory system during exercise.
To know cardiovascular adaptations during
long and short periods of exercise.
The function of the circulatory
system
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The circulatory system has three major
function:
Transport
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Body temperature control
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Moving things around the body in the blood stream
such as oxygen and nutrients like glucose.
Thermoregulation, moving blood near the skin cools
down the body. That’s why you look redder when you
exercise heavily.
Protection
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Moving anti-bodies around the body fighting diseases
and clotting cuts.
The structure of the heart
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Oxygenated blood
has more oxygen
and is found in the
arteries (except in
the pulmonary
artery).
Deoxygenated
blood has less
oxygen and is
found in the veins
(except in the
pulmonary vein.)
Task one
The cardiovascular system:
HEART
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Situated in the left-hand side of the
chest
Muscular pump whose purpose is to
drive the blood into and through the
arteries, to deliver it to the tissues
and working muscles
Considered as two separate pumps
Two chambers on the right, and two
chambers on the left side (the
septum separates these chambers)
• What are they?
Strokes of the heart
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Heart rate per minute is how many
time the heart beats in one minute.
Stroke volume is the amount of
blood pumped from the heart per
beat.
Cardiac output is the amount of
blood pumped from the heart in one
minute.
• Cardiac output = Stroke volume + Heart
rate
Circuits of the body
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There are two circuits of the body you
need to know:
Systemic
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The main circuit of the body, it carries oxygenated
blood around the body through arteries.
It carries deoxygenated blood back to the heart and
lungs through veins to be deoxygenated in the
pulmonary system.
Pulmonary
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Consists of the heart and lungs, deoxygenated from
the heart to the lungs to be oxygenated. The
oxygenated blood then goes back to the heart to be
pumped around the body.
Changes in heart rate during
exercise
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There is a anticipatory
rise due to hormonal
action.
Then there is a sharp
rise due to stimuli and
hormonal response.
The heart rate
steadies off during
constant maximal
exercise (heart rate
max)
Changes in the respiratory
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Tidal volume
increases.
Residual volume
increases.
Breathing rate and
the volume of
oxygen consumed
is increased due to
the onset of lactic
acid.
Adaptations to the body over
long periods of exercise.
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Increase in the
number of
capillaries.
Increase in the
efficiency of
gaseous exchange.
Lower resting heart
rate.
Aerobic adaptations in the
muscle during exercise
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Long aerobic
exercise such as
swimming or
running can
enlarge the slow
twitch fibres
allowing a greater
potential for
energy production.
Aerobic adaptations in the
muscle during exercise
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The size and
number of
mitochondria
increase.
There is an
increase in
myoglobin within
the muscle cell.
The onset of
fatigue is delayed
because of the
higher maximum
oxygen uptake.
Anaerobic adaptations in the
muscle during exercise
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Anaerobic activities
such as sprinting
and weightlifting
can cause
hypertrophy of the
fast twitch muscle
fibres.
Anaerobic adaptations in the
muscle during exercise
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Increased stroke
volume at rest and
during exercise.
Increased cardiac
output.
Decreased resting
blood pressure.
An increase in
haemoglobin (helps
carry oxygen along in
the red blood cells.
You must include this in your
assignment.
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Major muscles: triceps; biceps; quadriceps;
hamstrings; deltoids; gluteus maximus;
gastrocnemius; abdominals; obliques; pectorals;
trapezius; erector spinae; classification; location
Types of muscle: voluntary (skeletal); involuntary
(smooth); heart (cardiac)
Muscle movement: tendons; antagonistic pairs; types
of movement (concentric, eccentric,
isometric)
Effects of exercise: short-term effects of exercise eg
break down of muscle tissue; long-term
effects of exercise eg hypertrophy
Next seminar
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Introducing the Digestive system
including watching the third section
form the DVD entitled ‘anatomy for
beginners’.
Extended reading
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BTEC National diploma student guide
(the complete revision).