Download G.C.S.E - Effects of Exercise

Glossary of Terms
Aerobic
This means with the use of oxygen. Aerobic energy is energy that has to be
used over a fairly long period of time, with oxygen being used as an energy
source.
Anaerobic
This means without oxygen. Anaerobic energy is energy that is used over a very
short period of time, in short bursts, and which does not need oxygen as an
energy source.
Arterioles
Blood vessels into which the arteries sub-divide
Capillaries
The smallest of the blood vessels & the sites of exchange between blood and
tissue.
Cardiac Output (CO)
Amount of blood pumped out of a ventricle in one minute.
Oxygen Debt
A state where the body has used more oxygen than it can supply.
Respiration
The process by which oxygen is carried to the body cells and carbon dioxide is
removed.
Stroke Volume (SV)
Amount of blood pumped out of a ventricle during one contraction of the heart.
Tidal Volume (TV)
The volume of air you inhale or exhale with each breath.
Vasoconstriction
The narrowing of blood vessels (constricting)
Vasodilation
The relaxing of blood vessels (widening)
Hypertrophy
Growth of muscles as a result of regular physical activity
1
Short Term Effects of Exercise
The body does not like change. Body temperature is normally around 37C, & blood is
about 50% water. When you exercise you feel hot & lose water through sweating.
Various parts of the body have to adapt and change to return these to normal:
1)
Cardiovascular responses
2)
Cardio-respiratory responses
3)
Redistribution of blood
4)
Respiration in muscle cells
Even before we start to exercise, our bodies release the hormone adrenalin. This
prepares us for action by stimulating the circulatory & respiratory systems.
TASK 1 – Group work
Using the table below, write some physiological changes that happen to the body
when you do exercise.
Changes
Why
___________________
___________________
___________________
___________________
___________________
___________________
2
1) Cardio-vascular Responses to Exercise
Increase in Heart Rate
 H.R. increases with exercise.
 The heart pumps blood faster
around the body.
 The heart fills up fuller when
it relaxes, which stretches it
like elastic, so it contracts more
strongly.
 Pumps out more blood with
each beat.
Vascular Responses
 The veins squirt blood faster back
to the heart.
Effect on Stroke Volume
 S.V. increases with severe
exercise & with specialist
training.
Effect on Cardiac
Output
 C.O. increases
 It is the increase in H.R.
which accounts for the
increased C.O.
TASK 2: What is Stroke Volume:
[1]
________________________________________________________________
________________________________________________________________
TASK 3: What is Cardiac Output:
[1]
________________________________________________________________
________________________________________________________________
As a Result of these Changes:
 The C.V. system delivers more oxygen & glucose to the working muscles
 Carbon dioxide removed from muscle more quickly.
3
2) Cardio-respiratory Responses to Exercises
Effects of Oxygen Uptake
 The lungs work harder &
faster to take in oxygen
faster & to remove carbon
dioxide faster.
Breathing Frequency
 Rate of breathing increases
 Tidal volume increases
[The volume of air you inhale
or exhale with each breath]
Oxygen used during exercise
can be up to 20 times a person’s
normal oxygen uptake.
Therefore the depth of breathing
increases & the blood flow
through the lungs is increased.
Most of the
lactic acid gets
turned into
carbon dioxide
& water
Gaseous
exchange in
the lungs
speeds up
Delivery of Oxygen
 Heart & lungs work harder to deliver
oxygen to the muscles quicker.
 Blood flow is increased through lungs
Oxygen Debt
 Muscles need extra oxygen to get rid
of lactic acid, known as OXYGEN DEBT
TASK 4: How is the oxygen debt repaid?
[1]
________________________________________________________________
________________________________________________________________
4
3) Redistribution of Blood During Exercise
Some parts of the body differ in blood flow during exercise than at rest, and some
don’t.
 Carbon dioxide levels
increase in the blood.
 Lungs react
breathing faster &
deeper, increasing the
oxygen uptake.
 Blood flow increased
through the lungs
 Arterioles widen so BP
doesn’t get too high.
 BP increases
temporarily
Blood flows faster
When You Get Hot
 Blood gets shunted from where it
is needed less, to where it is
needed most. To allow for this,
blood vessels widen (vasodilation) &
constrict (vasoconstriction) at
different points
 Blood gets hotter
due to heat being
generated by
increased respiration
 To cool down, more
blood is shunted
close to the skin,
which reddens the
skin.
 You sweat which
cools you by
evaporation.
Adapted from Gallagher, Fountain & Gee (1997). Physical Education Through Diagrams (Pg.19)
5
4) Respiration in the Muscle Cells
First, the muscles start to work harder because of the increased stressed.
There are more muscular
contractions
Increased blood flow to the
working muscles.
More muscle fibres in
the muscles contract.
Increased muscle
contraction means that
more energy is required.
The temperature in
the muscles increases
Respiration in the
muscles cells
increases, using
oxygen & glucose.
Lots more carbon
dioxide is produced,
& some lactic acid.
TASK 5: What is respiration?
[1]
_____________________________________________________
_____________________________________________________
_____________________________________________________
As a Result of these Changes:
 Oxygen is used up quickly by the cells.
Oxygen
Glucose
 Glucose is used up quickly by the cells.
 Lots of carbon dioxide produced.
Muscle
 Some lactic acid produced.
 Lots of heat produced.
Carbon Dioxide
6
Lactic Acid
Heat
TASK 6: Complete the following paragraphs summarising the short term effects
of exercise. There is a selection of words below, but not all are used.
[10]
As soon as the body undertakes exercise, the ____________________ start to
work harder. Extra energy is required, therefore ____________________ speeds
up. This means the level of carbon dioxide in the blood ____________________.
The brain detects this and sends signals to your ____________________ and
____________________ to work faster.
The lungs breath ____________________ and deeper, increasing the
____________________. In turn ____________________ is removed faster and
____________________ taken in quicker.
The ____________________ beats faster, pumping ____________________
faster around the body. It ____________________ more strongly and pumps out
more blood with each ____________________.
Blood gets ____________________ from where it is needed less to where the
action is. To allow this to happen, blood vessels widen (this is known as
____________________) and constrict (this is known as
____________________)
The muscles generate more ____________________, so the blood gets hotter. The
____________________ reddens because more blood is shunted close to the
surface. ____________________ also helps to cool the body down.
SHUNTED
FASTER
OXYGEN
HEART
LUNGS
SKIN
MUSCLES
BREATHING
VASODILATION
RESPIRATION
VASOCONSTRICTION
TEMPERATURE
BLOOD
SWEATING
INCREASES
7
BEAT
CAPILLARIES
CARBON DIOXIDE
EVAPORATION
TIDAL VOLUME
HEAT
CONTRACTS
HEART
How the body changes during exercise - Summary
1. During
exercise, cell
respiration in
your muscles
increases. So
the level of CO2
in your blood
rises.
9. You sweat,
which cools
you by
evaporation.
8. The exercise
generates heat. So
your blood gets
hotter. More
blood is shunted
close to the skin to
cool down. This
makes your skin
redden.
2. Your brain
detects this and
sends a signal
to your lungs
to breathe
faster &
deeper.
3. Gas
exchange
speeds up –
more CO2
passes out of
the blood and
more O2 passes
into it.
7. This means
more O2
reaches the
muscles each
minute and
more CO2 is
carried away.
4. The brain also
sends a signal to
your heart to
beat faster –
your heart rate
goes up.
6. So cardiac
output rises
too. More
blood gets
pumped to the
muscles each
minute.
5. Your muscles
squeeze on
veins, sending
more blood back
to the heart.
This makes
stroke volume
rise.
8
Recovery After Exercise
We have seen the changes that take place during exercise. It takes some tine for
your body to recover after exercise:
Heart Rate
 Heart rate returns to
resting. The fitter you are
the faster this happens.
How Long to Recover?
The time it takes to recover depends on:
 The intensity
 Fitness level
Heavy training
sessions should
be followed by
light sessions or
allow 48 hours to
recover.
200
A_______
180
B_______
160
Heart Rate (BPM)
140
120
100
80
60
40
20
0
0
1
2
3
4
5
6
7
8
9
10
11
12
13 14 15 16 17
Exercise Time (mins)
18
19
TASK 7: From the graph charting heart rate during
exercise answer the following questions:
a) Label the ‘Fit’ and ‘Less Fit’ person on the graph. [1]
b) Give two reasons to explain your choice.
[2]
20
21
22
23
24
25
Lactic Acid
Removal
 Oxygen removes
lactic acid
(known as repaying
oxygen debt)
 Speeded up by
cooling down
Muscle Repair
 During training muscles can
suffer minor damage.
Stiffness & soreness take
time to clear:
_________________________________________
_________________________________________
_________________________________________
_________________________________________
Stretching as part of cool down
helps prevent stiffness.
_________________________________________
c) What is the resting heart for the Fit and Less fit
person?
[2]
Fit: ___________________________
Unfit: _________________________
9
Exercise may cause microscopic
tears in fibres.
Long Term Effects of Exercise
Long term training causes increased load & stress on the body. Various parts of the
body must adapt to accommodate these changes
(These changes depend on the type of training undertaken)
On the Cardiovascular & Circulatory Systems
Heart grows bigger
 After exercise HR returns to
normal faster
Holds more blood
 Volume of blood in body increases
Therefore increased production of red
blood cells & haemoglobin
Arteries become larger in size
Contracts more strongly
Arteries become more elastic
 Resting Heart rate (RHR) falls
More efficient pump
Blood pressure falls
On the Respiratory System
 The muscles involved in breathing become stronger
(intercostal muscles& diaphragm)
 Increased capillary growth
around alveoli
 Chest cavity increases in size.
Therefore we can breathe in more air
and continue to do so for a longer time
 More blood carried to alveoli
 Don’t get tired so quickly
 Work closer to VO2 max
(The max amount of O2 that we can
take in and use in our bodies in one
minute)
Lungs expand further
More alveoli available for gas exchange
More 02
 We can increase our VO2 max by as
much as 20%
C02 removed
 Overall – the rate at which O2 is moved
to the muscles and CO2 is removed is
faster. So you don’t get tired so fast. [1]
TASK 8
Why can the lungs expand further?
________________________________________________________________
________________________________________________________________
10
On the Body in General
 Tendons become stronger
 More capillaries form around
the muscle
 Ligaments become more flexible
 Muscles better at tolerating lactic
 Bones become stronger as more calcium
is produced
 Muscles contract more strongly
 More calcium is produced
 Muscles store more ATP, CP
& glycogen
 Fast twitch fibres increase in size
(hypertrophy)
TASK 9
[4]
Using the changes given so far, work out which are caused by Aerobic Training,
Anaerobic Training & Resistance Training
Aerobic Training
Anaerobic Training
Resistance Training
1) Reduced RHR
1) Fast twitch muscle fibres
1) Hypertrophy of muscles
2) Blood pressure reduced
increase in size
2) More of ATP, CP & glycogen
3) ________________________
2) More of ATP, CP & glycogen
stored in muscles
stored in muscles
3) ________________________
3) ________________________
__________________________
__________________________
__________________________
__________________________
4) ________________________
__________________________
__________________________
4) ________________________
__________________________
__________________________
5) ________________________
__________________________
__________________________
__________________________
__________________________
__________________________
__________________________
4) ________________________
__________________________
__________________________
5) ________________________
__________________________
__________________________
11
Past Paper Questions
1) (i) Heart rate changes with the introduction of exercise. How can heart rate be used in
sport and the assessment of physical fitness?
[2]
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
(ii) During exercise certain other physiological changes take place. List two other changes
and state why these take place.
[4]
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
2) Muscles obtain energy from glucose in a process called aerobic respiration.
i) What other substance is needed for this?
[1]
____________________________________________________________________
ii) Name the two waste products and explain how they are excreted.
[2]
____________________________________________________________________
____________________________________________________________________
3) When you exercise your body loses heat by evaporation. Explain how this process takes
place:
[2]
____________________________________________________________________
____________________________________________________________________
4) When you exercise, some blood is shunted to where it is needed more.
[1]
Give an example: ______________________________________________________
____________________________________________________________________
5) What effect does exercise have on cardiac output?
[2]
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
12
6) These are two changes that take place in the body during a training run:
a) His heart beats faster
[1]
b) He breathes more heavily
[1]
Explain how each change is helpful to the athlete:
a) __________________________________________________________________
____________________________________________________________________
b) __________________________________________________________________
____________________________________________________________________
7) a) What happens to an individual’s heart rate when they start exercising?
[1]
____________________________________________________________________
____________________________________________________________________
b) Why is this an advantage to the performer?
[1]
____________________________________________________________________
____________________________________________________________________
8) ”During strenuous sporting activity visible and immediate changes to the body can take
place”
Describe three visible and immediate changes that can take place to the body during
strenuous sporting activity
[3]
I _______________________________________________________________
________________________________________________________________
________________________________________________________________
II ______________________________________________________________
________________________________________________________________
________________________________________________________________
III _____________________________________________________________
________________________________________________________________
________________________________________________________________
9) Explain how the blood circulatory system helps to stop the body over-heating during
exercise.
[1]
____________________________________________________________________
____________________________________________________________________
____________________________________________________________________
10) Why does the body get warmer during exercise?
[1]
____________________________________________________________________
____________________________________________________________________
13
11) Give two long-term effects of aerobic exercise on the body and explain how each can
help to improve performance.
Answer the question by completing the table below.
Long-term effects of aerobic exercise
[4]
Explain how each can help to improve
performance.
_______________________ _______________________
_______________________ _______________________
_______________________ _______________________
_______________________ _______________________
I
_______________________ _______________________
_______________________ _______________________
_______________________ _______________________
_______________________ _______________________
_______________________ _______________________
II
_______________________ _______________________
_______________________ _______________________
_______________________ _______________________
12) “Taking part in sporting activity makes the body respond by changing both immediately
and adapting over time to the level of activity.”
Outline four short-term effects of exercise on the body.
[4}
I _______________________________________________________________
________________________________________________________________
II ______________________________________________________________
________________________________________________________________
III _____________________________________________________________
________________________________________________________________
IV _____________________________________________________________
________________________________________________________________
14
13) The graph below shows the heart rate of two sixteen year old athletes when training at
the same intensity.
(i) Which athlete is the fitter, A or B?
[1]
________________________________________________________________
(ii) Using information from the graph to help you, give two reasons for your answer. [1]
I
___________________________________________________________
II
___________________________________________________________
TOTAL = 58 MARKS
2005/06
15