Cardiovascular system, respiratory system.

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AS PE
Book 2
Anatomy & Physiology
Cardiovascular & Respiratory systems
Name .........................................................................
1
KEY TERMS you need to be aware of and learn for the cardiovascular/respiratory system
KEY TERM
Aerobic
Anaerobic
Deoxygenated
Oxygenated
Pulmonary
Cardiac cycle
Bradycardia
Hypertrophy
Stroke volume
Sub maximal
Venous return
Ventricular
contractility
Oxygen debt
Motor nerves
Sensory nerve
Receptors
Venous return
Starling’s law
Smooth muscle
Vasodilate
Vasoconstrict
Venodilate
Venoconstrict
Chemoreceptor
Baroreceptor
OBLA
Enzyme
Blood viscosity
Myoglobin
Ergogenic
VO2 max
Lactate
threshold
DEFINITION
A process taking place in the presence of oxygen
A process taking place with insufficient oxygen
Blood depleted of oxygen
Blood saturated/loaded with oxygen
Linked to the lungs
Events of one heart beat
A resting heart rate (HR) below 60
Increase in size of heart muscle wall
Blood ejected from heart ventricles every beat
Exercise performed at an intensity below an athlete’s maximal
aerobic capacity or max VO2 – hence it represents aerobic work
Blood returning to the heart
Capacity of heart ventricles to contract
Additional oxygen consumption during recovery, above that usually
required when at rest
Nerves which stimulate muscle tissue causing motor movement
Nerves which transmit information to Central Nervous System e.g.
from receptors to the CCC (cardiac control centre)
Sense organs that pick up stimuli, which are relayed to the brain
(medulla oblongata)
Blood returning to the heart
SV dependent upon venous return = any increase in VR causes an
increase in SV & Q
Involuntary muscle found in blood vessel walls
Widening of arterial blood vessels
Narrowing of arterial blood vessel walls
Widening of venous blood vessels
Narrowing of venous blood vessel walls
A sensory receptor that is selective for a chemical substance
A sensory receptor that responds to pressure or stretch. Refers to
the blood pressure receptors of the carotid artery & aorta
Onset of blood lactate accumulation, where the body produces lactic
acid quicker than it can remove it, causing an increase in lactic acid
levels which eventually cause muscle fatigue
Protein that acts as a catalyst for bodily reactions
Resistance to blood flow
Red pigment in muscles that store & transport O2 to mitochondria
within muscles
Anything that improves performance
Maximal oxygen consumption
Start of anaerobic work
2
NOTE
The Cardio system
Review of heart structure & function
Aerobic work refers to exercise that ................................................................................................
Examples
Anaerobic work refers to exercise that ............................................................................................
Examples
The aerobic system refers to three systems in order to ensure constant distribution of
oxygen to the muscles during exercise, the heart, the vascular and the respiratory
systems.
Heart’s conduction system linked to the cardiac cycle
The heart has a dual-pump action with two separate pumps that work simultaneously to
pump blood to two different destinations.
The right side pumps _______________________ blood towards the lungs
The left side pumps ________________________ blood towards the rest of the body
Label the heart
3
Conduction system
The heart is myogenic – it generates/controls its own electrical impulse called the cardiac
impulse.
Describe the conduction system.....
Cardiac cycle - add in the arrows of the blood flow through the cardiac cycle for each
of the three stages
Stage 1 Diastole
Relaxation/passive filling phase lasting 0.5 seconds
Deoxygenated blood enters RA from superior/inferior vena cava
Oxygenated blood enters left atrium from pulmonary veins
Rising blood pressure against AV valves forces blood into ventricles
through tricuspid & bicuspid valves
EDV - volume of blood after filling
Stage 2 Atrial systole
Contraction of left & right atria
Rising atrial pressure forces remaining blood into the L&R ventricles
Stage 3
Ventricular systole
Contraction of both L&R ventricles, increase in ventricular pressure
forces blood out of L&R ventricles (SV)
RV forces blood from pulmonary valve into pulmonary artery to lungs
LV forces blood from aortic valve into aorta to the body tissues
A reserve volume of blood will be left in the ventricles (ESV)
Bicuspid & Tricuspid valves remain shut
Aortic & pulmonary valves close after ventricular systole to prevent
blood flowing back into ventricles
Relationship between and resting values of Heart Rate, Stroke Volume
& Cardiac Output
4
Heart Rate (HR)
The number of times the heart
beats per _______________
Stroke Volume (SV)
The volume of blood ejected
from the heart per _________
The average resting heart rate
is ____________ bpm
The average resting SV is
approx __________ml
EDV is volume of blood left in
ventricles at end of filling stage
ESV is volume of blood left in
ventricles at end of contraction
SV = EDV – ESV
Cardiac Output (Q)
This is the volume of blood
ejected by heart ventricles in
______________ min
Q = SV x HR
Work it out
Using the calculations and information above, what would an average person’s cardiac
output be at rest?
What is your cardiac output?
The heart’s response to exercise
Exercise Intensity
Resting
SV
60/80 ml
HR
70/72 bpm
Q
5 L/min
Complete the following table
Sub-maximal (mod)
80/100 ml untrained
160/200 ml trained
Up to 100/130 bpm
Maximal
220 - age
20 – 40 L/min
5
The HR is constantly changing before, during and after exercise. The type of change
depends on the activity that you are taking part in...
Explain what is happening to the HR during the following stages of
exercise. Use the graph and each number 1-6 to help you....
Task
160/
200
5b
4
3
2
60/
72
5a
6
1
Prior
Exercise
Recovery
6
Cardiac Control Centre CCC
The heart is regulated via stimulation of the SA node. The CCC is controlled by the
autonomic nervous system.
There are three main factors that affect the activity of the CCC, Neural, Hormonal and
Intrinsic control.
Complete
Chemoreceptors – in muscles, aorta &
carotid arteries
Neural
Neural
Neural
Baroreceptors – in aorta & carotid
arteries
CCC in medulla
oblongata
Proprioreceptors – in muscle
spindles/joint receptors, golgi tendon
organs
Venous Return
Temperature
Adrenalin – from adrenal glands
Intrinsic
Intrinsic
Hormonal
The CCC will detect whether to increase or decrease HR through the initiation of either
the sympathetic or parasympathetic nervous system.
Sympathetic nerves
_______________________ HR
Parasympathetic nerves _______________________ HR
The heart’s link to a healthy lifestyle
The impact of regular participation in physical activity and a healthy lifestyle in relation
to the heart is clear.
Using your notes, text books and the article ‘physiological adaptations to
aerobic training’ in PE Review April ’08, answer the following exam type
question..
1a) Taking part in physical activity is considered essential to maintaining a healthy
lifestyle. Does the type of activity make a difference?
1b) What are the positive impacts on the heart of participating in different types of
physical activity?
[5 marks]
7
The Vascular system
Blood & Blood vessel system
The vascular system controls blood supply. It consists of blood and blood vessels that
transport & direct O2 and CO2 to and from the lungs, heart and body tissues/muscles.
Circulatory networks - blood vessel structure
 All blood vessels have three layers except for single walled capillaries
 Artery & arteriole walls have a large muscular middle layer of involuntary smooth
muscle that allows them to vasodilate (widen) and vasoconstrict (narrow) to alter
their shape and size to regulate blood flow
 Arterioles have a ring of smooth muscle surrounding the entry to the capillaries
called precapillary sphincters that control blood flow



Capillaries have a very thin, one-cell thick layer to allow gaseous exchange to take
place
Larger veins have pocket valves to prevent the back flow of blood and direct blood
in one direction back to the heart
Venules & veins have a much thinner muscular layer, allowing them to venodilate
and venoconstrict to a lesser extent and a thicker outer layer to help support the
blood that sits within each valve
Pulmonary circulation system
Systemic circulation system
8
Venous Return Mechanisms
Venous return is the deoxygenated blood returning to the heart. Starling’s Law states
that ‘Stroke Volume is dependent upon venous return’.
If VR increases, so does SV/Q. If VR decreases, so does SV/Q.
There are five mechanisms that help to maintain or increase VR during exercise to ensure
that SV & Q are sufficient to supply the demand for oxygen.
Complete
Give a short description of each and include a diagram where possible....
 Pocket valves
 Skeletal muscle pump
 Respiratory pump
 Smooth muscle
 Gravity
TASK
In small groups, answer the following.....using your knowledge, show how
venous return may impact on the quality of performance. You may
consider before, during & after physical activity.
9
Blood pooling
VR requires a force to push blood back towards the heart. If there is insufficient
pressure to push blood back towards the heart, it causes blood pooling. This is why an
active cool down is important as it prevents blood pooling after exercise by maintaining
the muscle and respiratory pumps.
Redistribution of cardiac output from rest to exercise involves a process called the
Vascular Shunt Mechanism
Complete
Approx 80% Q
Organs
......................
Cardiac Output (Q)
Approx 20% Q
Muscles
At rest
.......................
<<intensity>>
During exercise
Muscle ______________________ and pre-capillary ______________________
vaso___________________ to allow more blood to the working muscles
Organ _______________________ and pre-capillary ______________________
vaso __________________ to reduce blood supply to the organs
Exam tip
Up to 4 marks are available for explaining the vascular shunt mechanism: 2 marks for
vasodilation of muscle arterioles and pre-capillary sphincters and 2 marks for
vasoconstriction of organ arterioles and pre-capillary sphincters.
Take it further
Consider the following scenario which is a problem faced by all
athletes.
A cyclist completes an exhausting high intensity training programme and immediately
stops, climbs off the bike and stands against the wall whilst recovering. Feeling light
headed or dizzy they faint, falling to the floor. Use your knowledge of VR to explain
this sequence of events and give your recommendations to avoid recurrence.
10
Vasomotor control centre VCC
The VCC regulates the redistribution of Q by controlling the vascular shunt mechanism.
During exercise, VCC receives information from: chemoreceptors in muscles, aorta and carotid arteries that there is an increase in
lactic acid and CO2 and a decrease in O2 and pH levels.
 Baroreceptors in aorta & carotid arteries that systolic blood pressure has
increased/decreased
When the VCC receives this information, it responds by sending messages via the
sympathetic nervous system and controls the blood flow to organs & muscles through the
following....
Complete
Vasomotor control (VMC)
Vascular Shunt mechanism
Organs
Muscles
Increased sympathetic stimulation
Vasoconstriction of arterioles
....and pre-capillary sphincters
Decreased blood flow/Q to
capillaries or non-essential organs
?
TASK
Test your understanding and knowledge and answer the following exam
question
Venous return is the transport of deoxygenated blood to the right side of the heart.
Give three mechanisms which maintain venous return during exercise.
An increase in venous return can improve performance. Explain how the increase in blood
flow affects cardiac output.
[6 marks]
(Jan ’10)
11
O2 & CO2 Transport
Efficient transport of O2 and CO2 is important in physical activity as it prolongs duration
of anaerobic and aerobic activity, delays anaerobic threshold which increases the
possible intensity /work rate for the activity and it speeds up recovery during and after
exercise.
O2 and CO2 are transported via the blood in the following way:CO2
O2
70% combined with water in
97% in haemoglobin
In RBCs as oxy-haemoglobin
red blood cells as carbonic acid
3% within blood plasma
23% in haemoglobin as
carbaminohaemoglobin
7% dissolved in plasma
Exam Tip
It is easy to recall, for two marks, that Hb and plasma both transport O2 & CO2
Warm Up / Cool Down effects on the vascular system
Warm Up
Gradual increase in blood flow due to
vascular shunt
Vasoconstriction & Vasodilation info
Increase in body/muscle temperature
increasing transport of enzyme activity
required for energy systems & muscle
contraction
Increase in body/muscle temperature
which decreases blood viscosity, improving
blood flow to working muscles and increases
dissociation of O2 from haemoglobin
Decreases OBLA due to the onset of
anaerobic work without a warm-up
Cool Down
Keeps metabolic activity elevated, which
decreases heart rate and respiration
gradually
Maintains vasodilation of muscle
arterioles/precapillary sphincters, which
keeps capillaries dilated to flush muscles
with oxygenated blood
Maintains respiratory/muscle pumps, which
maintains venous return, which:
Prevents blood pooling in veins
Maintains blood flow (SV & Q) to
supply O2 which maintains blood
pressure
Increases the removal of blood and muscle
lactic acid and CO2
12
Blood Pressure
Blood Pressure is essential to apply the force needed to circulate the blood around the
body. It is the ‘pressure exerted by blood against the (arterial) blood vessel walls’
Contractive force of the heart ventricles
Forces blood through the arteries
Blood pressure is expressed as
Systolic
Diastolic
The average blood pressure (resting) is
(ventricular systole)
(ventricular diastole)
120mmHg (in aorta)
80mmHg
What is your blood pressure?
The contraction of the heart ventricles represents the high pressure force of the ‘blood
flow’ leaving the aorta, so any increase in Q will cause Bp to increase
Mm Hg
Bp changes during different types of physical activity
300
250
200
150
100
50
Long



Rest
Aerobic
exercise
2-arm curl
heavy load
2-leg press
heavy load
term effects
Resting Bp may decrease with continued endurance training
Resting Bp is generally lowered in people who have mild/mod hypertension
Endurance training can reduce the risk of developing high Bp
Task
Using information from text book (pgs 90/91), explain why Bp changes
and the differences in systolic & diastolic pressures. For an A/B answer,
you will need to do some extra research.
13
Hypertension & Bp
Hypertension is long-term, enduring high Bp, where treatment is normally provided if Bp
exceeds 140/90mmHg.
Effects of hypertension include: Increased workload on the heart
 Accelerates atherosclerosis and arteriosclerosis
 Causes arterial damage, increasing the risk of a stroke and heart failure
Regular exercise and an active lifestyle may prevent high Bp indirectly by reducing the
risk of obesity and reducing stress, which may help to keep blood pressure at moderate
levels.
Causes of high Bp / Hypertension
Controllable causes
Uncontrollable causes
Exam question
Blood pressure is essential to apply the force needed to circulate the blood around the
body to supply oxygen to the working muscles.
i)
Explain the difference between blood pressure and hypertension
ii)
What changes occur to blood pressure during physical activity
[5 marks]
14
Impact of physical activity on the cardiovascular system in reference to a lifelong
involvement in an active lifestyle.
Cardiac Heart Disease (CHD)
Coronary heart disease is the single largest cause of death in the Western world and is
linked to a sedentary lifestyle.
There is a cause – effect relationship where two blood vessel diseases lead to the two
heart related diseases...
Blood vessel CHD
Arteriosclerosis
Atherosclerosis
Heart related CHD
Angina
Heart Attack
Using the text book (pgs 93/94), write down 3-4 issues relating to each of the diseases...
Arteriosclerosis -
Atherosclerosis -
Angina -
Heart Attack -
15
CHD risk factors
There are five risk factors associated with developing CHD
1)
2)
3)
4)
5)
If you score relatively low on the risk table, you will have more protection from CHD. If
you score highly in 2 or more of the risks, you have more chance in developing CHD.
Task
Calculate your risk factor using the risk table on page 95 of the test
book.
Lessening the risk
Physical activity can help to protect us from CHD in several ways
 Improves heart efficiency – hypertrophy, lowers RHR, slowing down heart
deterioration & improve length of an individual’s quality of life
 Improves vascular efficiency (vascular shunt) improving coronary blood flow
 Decreases blood lipids (LDL), reducing athero/arteriosclerosis
 Increases HDLs which act as scavengers to remove cholesterol
 May reduce Bp and risk of developing hypertension
 Alleviates tension/stress helping reduce hypertension
 Reduces body fat / obesity through controlling body weight
 Acts as a stimulus for a healthier lifestyle – to stop smoking/improve diet (a
healthier & regular physical activity can chip away at fatty deposits which block
precious oxygen from getting to your heart and lead to a lifelong involvement in an
active and healthy lifestyle
Recommended physical activity guidelines for protection against CHD
The ACSM (American College of Sports Medicine) outline 3 guidelines to follow:1)
People should engage in moderate activity for at least 30mins 5-7 days a week,
although higher intensity exercise can provide greater protection
2)
People with or at risk of heart disease
i)To improve cardio-respiratory fitness 3-4hrs/wk of regular physical activity
ii) To halt progression of fatty plaques in the arteries, 4-5hrs/wk
iii) For regression of fatty plaques, 5-6hrs/wk
1)
Activity does not necessarily need to be done in continuous blocks – accumulation
of activity will gain the same benefits as from a single longer session.
Trial
10
marker
Using the information above, answer the following trial 10 marker...
Evaluate critically the impact of physical activity on CHD
[10marks]
FURTHER READING – to help with this task, read the ‘breath life into your
heart with exercise’ article in PE review, Sept ’08.
16
Response of the cardiovascular (respiratory) system to physical activity
There are three main respiratory structures: Pulmonary ventilation - the breathing of air in and out of the lungs
 External respiration - exchange of 02 & C02 between lungs & the blood
 Internal respiration - exchange of 02 & C02 between blood & muscle tissues
Mechanics of breathing is understood by linking 5 steps
1) Muscles - to actively contract or passively relax to cause....
2) Movement - of the ribs, sternum & abdomen which causes....
3) Thoracic cavity volume - to either increase or decrease which causes...
4) Lung air pressure - to either increase or decrease which causes
5) Inspiration or Expiration - air breathed in or out.
Complete the following table....
Inspiration at rest
1
Muscles
Diaphragm contracts – active
External intercostals contract
2
Movement
Diaphragm flattens / pushed down
Ribs / Sternum moves up and out
3
Thoracic cavity volume increases
4
Lung air pressure decreases below
atmospheric air (outside)
Air rushes into the lungs
5
Inspiration during exercise
1 Muscles
Diaphragm contracts
External intercostals contract
What muscles also contract?
2 Movement
Diaphragm flattens with
_________________
Increased lifting of ribs & sternum
3 _______________Thoracic cavity
volume
4 ______________air pressure in lungs
5 More air rushes ___________the lungs
17
Expiration at rest
1
Muscles
Diaphragm relaxes – passive
External intercostals relax
2
Movement
Diaphragm pushed upward
Ribs / Sternum move in and down
3
Thoracic cavity volume decreases
4
Lung air pressure increases above
atmospheric air (outside)
Air rushes out of the lungs
5
Task
Expiration during exercise
1 Muscles
Diaphragm relaxes
External intercostals relax
What muscles contract to help with
expiration?
2 Movement
Diaphragm pushed _____ harder with
_________________
Ribs & sternum pulled in and down
3 _______________________Thoracic
cavity volume
4 ______________air pressure in lungs
5 More air pushed ___________of the
lungs
Count the times you breath in one minute (a breath is in and out)
Take part in aerobic or anaerobic activity for 2-3 mins
Count the times you breath in one minute again immediately after activity
What do you find?
EXAM TIP
Respiratory muscles initiate breathing by increasing and decreasing the volume of
the lung cavity and therefore lung pressures. Do not make the mistake of thinking
the lungs or pressure differences themselves initiate breathing
Exam question
May 09
During exercise, the mechanics of breathing allow for greater volumes of air to be
inhaled per breath. Describe how the mechanisms of neural control cause changes to the
mechanics of breathing during exercise.
[5 marks]
18
Respiratory volume
This is calculated similar to the efficiency of the heart. There are 3 definitions and
values that you have to consider...
Lung Volumes



Tidal Volume (TV) - the volume of air inspired or expired per breath - approx
500ml at rest
Frequency (f) - the number of breaths taken in 1 minute - approx 12-15 breaths
at rest
Minute Ventilation (VE) - the volume of air inspired or expired in 1 minute. VE
can be calculated by multiplying the tidal volume with the frequency of breaths in 1
minute.
Calculate your VE using the information collected from the previous task (breathing
per min)
VE
=
=
TV x f
500ml x ____
=
ml/min
=
L/min
EXAM TIP
Make sure you don’t confuse these values with those of the heart.
Lung volume changes during exercise.....
Complete the following table
Lung Volume
Definition
Tidal volume
X
Volume of air
inhaled/exhaled per breath
during rest
Number of breaths in one
minute
Volume of air
inspired/expired in one
minute
Frequency
VE
Resting
volume
500ml per
breath
Change due to exercise
12-15
Increases:
6-7.5 L/min
Increases:
19
Increases:
Gaseous Exchange
The exchange of gases (O2 and CO2) is called diffusion
Diffusion = movement of gases from an area of high pressure to an area of low pressure
Diffusion gradient = the difference between high & low pressure
The bigger the gradient, the greater the diffusion and gaseous exchange takes place
How do you know whether blood has high or low partial pressure (PP) or O2 or CO2?

Oxygenated blood =
_________________
High PP of ________________
Low PP of

Deoxygenated blood =
_________________
High PP of ________________
Low PP of
When we exercise, both internal & external respiration increase
Why?


Oxyhaemoglobin dissociation curve
Internal respiration
- During exercise 4
factors shift the curve right because of increase
in O2/CO2 diffusion
1.
2.
3.
4.
20
External respiration - The increase in diffusion gradient for both O2 and CO2 across
the alveoli-capillary membrane = quicker and greater amount of gaseous exchange to
ensure haemoglobin is almost fully saturated with oxygen
Deoxygenated venous blood returning to the lungs have the following:

High PP of _____________________
Lower PP of ____________________ than at rest
Respiratory Control Centre (RCC)
Where is the RCC located? ________________________
What does the RCC regulate via the respiratory muscles?
____________________________
Do the respiratory muscles work under voluntary or involuntary control?
____________________________
The respiratory muscles are stimulated at rest and during exercise.
Factors affecting the RCC
At rest....the medulla oblongata (1)
contains Inspiratory and expiratory
centres. When chemoreceptors (2),
active muscles (3) and increasing
temp (4) stimulate the Inspiratory
centre (5), this stimulates the
Inspiratory muscles (6) to contract,
increasing the volume of the thoracic
capacity and drawing air into the
lungs. Inspiratory muscles passively
relax, decreasing the volume of the
thoracic cavity and air is expired.
During exercise.....As (1) to (6) above, but during exercise the Inspiratory centre
stimulates additional respiratory muscles (7) which increases the depth of breathing.
This stimulates the stretch receptors (8) in the lungs, which stimulate the expiratory
centre (9) to stimulate the expiratory muscles (10) to contract. This causes a forced
expiration which reduces the duration of inspiration. This decreases the depth and
therefore increases the rate of breathing.
21
Ventilatory response to various intensities of exercise.....
Complete the following table, using the information given...
1.
2.
3.
4.
5.
6.
Anticipatory Rise...prior to exercise in all 3 work intensities you release hormones
and adrenaline, which stimulate the respiratory control centre (RCC)
Rapid rise in VE.....at the start of exercise due to neural stimulation of RCC by
muscle/joint proprioceptors
Slower increase/plateau....in sub maximal exercise due to continued stimulation of
RCC by proprioceptors, but with additional stimulation from temperature and
chemoreceptors (increase in temp, CO2 and lactic acid levels and a decrease in
blood O2). The plateau represents a steady state where the demands for oxygen
by the muscles are being met by oxygen supply
Continued but slower increase....in heart rate towards maximal values during
maximal work due to continued stimulation from the receptors above and
increasing chemoreceptor stimulation due to increasing CO2 and lactic acid
accumulation
Rapid decrease....in VE once exercise stops due to the cessation of proprioceptor
and decreasing chemoreceptor stimulation
Slower decrease....towards resting VE values
The more intense the period of exercise is, the longer the elevated level of respiration is
required to help remove the increased by-products of exercise eg. Lactic acid.
Draw in the ventilatory response to light, moderate & heavy
exercise intensities
Task
140
Start
4
Stop
120
Heavy
100
Moderate
80
3
60
2
Light
40
1
6
20
0
5
Exercise
-2
-1
0
1
2
(min)
22
3
4
5
Time
6
7
Things to remember...
 The exchange of oxygen and carbon dioxide takes place in the lungs and tissues
and is called external and internal respiration
 Remember the close similarity between the heart and respiratory equations and
don’t confuse them when answering heart/respiratory volume questions.
Respiratory refers to air, heart refers to blood
 You will not be required to know actual partial pressures (PP) – only whether the PP
is higher or lower and the reasons why
EXAM TIP
You may be required to describe and explain the changes in VE from resting to submaximal and maximal workloads, so is good to learn this well
Exam questions
Jan ‘09
During exercise there is an increased supply of oxygen to the working muscles. Describe
the processes of internal respiration which allow more oxygen to be diffused into the
muscle cell during exercise.
[5 marks]
Altitude effects on the respiratory system
Exposure to high altitude has a significant effect upon performance and is also
recognised as an ergogenic training aid.
At high altitude (above 1500m) the PP of oxygen decreases (hypoxic) and this has a
series of knock-on effect which decreases the efficiency of the respiratory processes
3.Decrease in O2 & Hb association
4.
(HbO2) during external respiration
5.A reduction of O2 available to
2.
muscles – due to a reduction in
diffusion gradient & O2 exchanged
/ during internal respiration
1.Decrease in pp O2 in
alveoli due to a decrease
6.Net effect
in pp O2 in the
atmospheric air
23
Impact of physical activity on the respiratory system with reference to lifelong
involvement in an active lifestyle
The respiratory system will increase its efficiency to supply O2 to the working muscles,
especially during higher intensities of exercise through regular physical activity training.
This is primarily due to an increase in efficiency of:
 Respiratory structures - Increased alveoli, increasing surface area for diffusion
increased elasticity of respiratory structures, increased longetivity of respiratory
structure efficiency
 Breathing mechanics - Increased efficiency/economy of respiratory muscles,
reducing fatigue
 Respiratory volumes - Volumes increase increasing performance
 Gaseous exchange / diffusion - Increased VO2
Through increasing this efficiency of the respiratory system, VO2 max and the lactate
threshold increase which in turn improves performance.
Research
- what is VO2 max and lactate threshold?......in pairs, present a poster
showing what they are and their importance/issue within sports
performance......
VO2 max -
Lactate threshold -
Exam question
1. In the 1968 Olympics held in Mexico at an altitude over 2300m there were new
world records established in the throw/jump and sprint events but none in any of
the distance events.
Explain the effects of altitude on the respiratory system and how this may
influence performance of different intensities of physical activity.
[5 marks]
24
Asthma and an active lifestyle
Symptoms – asthma is the reversible narrowing of airways leading to hyperirritability of
airways, coughing, wheezing, breathlessness or mucus production
How is it measured? - by inhaling into a spirometer and measuring the exhaled volume
of air.
Triggers - Drying of the airways causing an inflammatory response which
constricts/narrows airways, termed bronchoconstriction. Common triggers include
exercise, known as EIA (exercise induced asthma), exhaust fumes, dust, hair and pollens.
Performance effects - Asthma can reduce performance, especially in elite aerobic
athletes and is increasingly common in athletes.
Management - what medical and non-medical treatments are there?
Medical - inhalers
Bronchodilators - which are relievers and relax muscles around airways and are normally
taken before exercise or in response to symptoms
Corticosteroids - which are preventers and suppress the chronic inflammation and
improve the pre-exercise lung function and reduce sensitivity of the airway structures.
A daily dose is normal for mild asthma
Non medical
A warm-up – at least 10-30mins at 50-60% MHR which provides a refractory period for
up to 2hrs so you can exercise without triggering EIA
Dietary modifications of reducing salt and increasing fish oils and vitamins C + E as this
has been shown to reduce inflammatory response to EIA
Task
- what is IMT (Inspiratory Muscle Training)?.....discuss the use of
the ‘POWERbreath’ training aid in increasing performance...
25
Smoking and an active lifestyle
Smoking effects
 Impairs lung function and diffusion rates
 Increases damage and risk of respiratory diseases, infections and symptoms
 Irritates/damages/constricts/reduces elasticity of respiratory structures
 Triggers asthma, shortness of breath, coughing/wheezing, mucus/phlegm
How does smoking effect sports performance?
Think of a headline you would give to this picture....
Give 5 bullet points that you can think of regarding this
picture
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Using the information from above, additional research and from the text book page
121, write up an article explaining the effects of smoking on sports performance....
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Exam questions
May ‘09
1. Give two ways in which oxygen is transported in the blood. Describe the effect of
smoking on the transport of oxygen in the blood.
[5 marks]
Jan ‘09
2. During exercise there is an increased supply of oxygen to the working muscles.
Describe the processes of internal respiration which allow more oxygen to be
diffused into the muscle cell during exercise.
[5 marks]
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CARDIO-RESPIRATORY CONTROL
Summary of the cardio-respiratory control during exercise......
Factors
affecting
the
activity of
the control
centres
Hormonal
adrenaline
Proprioceptors
Increase in motor movement
Intrinsic
Increase in venous return
Increase in temperature
Baroreceptors
Lung stretch receptors
Blood pressure
Chemoreceptors
Increase in PP CO2
Decrease in pH
Decrease in PP O2
RCC
VMC
CCC
Medulla Oblongata
Sympathetic
Nervous system
CCC
O
Control
structure
Effect on
cardio-
Arterial & venous
blood vessel
walls
Vascular shunt
respiratory
system
Inspiratory
muscles
Sympathetic
nervous
system
Accelerator nerve
Phrenic & intercostals
nerves
Venomotor tone
Means of
transporta
tion
Vasomotor tone
RCC
Inspiratory
Expiratory
Centre
Centre
Medulla
RCC Oblongata
SA node
Expiratory
muscles
Increases
depth of
breathing
Increases
rate of
breathing
Vasoconstriction
&
Vasodilation
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Parasympathetic
nervous system
Vagus nerve
Control
Centres
Increase
HR
Decrease
HR
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