From strength
to strength
From strength
to strength
The muscle that can
pull with the greatest
force is the soleus, just
under the calf muscle.
This is the muscle that
stops us from falling
backwards when we
stand.
Draft only
©Pearson Education: Jules Selmes
Learning objectives
At the end of the lessons, you will be able to:
• understand that continuous or rapidly repeated
contraction of muscle results in fatigue
• explain that different types of muscle fibre have
a significant effect on sporting ability
Learning objectives
• state that muscle size is related to muscle strength
• work accurately and safely, individually and with
others, when collecting first-hand data
• interpret data relating to the effects of exercise on
the human body.
Background science
The amount of
force a muscle can
produce is related to
its size — the larger
the muscle the
greater the force
that it can produce.
©PCN Photography
Background science
The role of muscles
In many sports, muscles are
not required to produce a lot
of force but need to be able
to contract and relax for
prolonged periods of time.
Large muscles are not
needed in these types
of sports.
Background science
Muscle fibres
Muscles are made
up of muscle fibres.
There are two types of muscle fibre: fast-twitch
muscle fibres and slow-twitch muscle fibres.
Background science
Fast-twitch muscles
Slow-twitch muscles
power events e.g. javelin endurance events e.g. crosscountry skiing
fast contraction speed
slow contraction speed
high force production
low force production
low capillary density
high capillary density
low mitochondrial density high mitochondrial density
fatigues quickly
slow to fatigue
little myoglobin
rich in myoglobin
Background science
Percentage of muscle fibres
You cannot change the
percentage of muscle fibres
that you are born with.
Which fibre type do you
think you have a greater
percentage of in your
muscles? Give a reason
for your answer.
Sprinters have
higher percentages
of fast-twitch muscle
fibres compared to
marathon runners.
Background science
How do muscles help these
people perform at their best?
©Alamy Images: ITAR-TASS Photo Agency
©Shutterstock.com: EcoPrint
©Getty Images:
Jed Jacobsohn
Background science
Yoga increases flexibility and strengthens muscles.
The muscles do not produce movement, they
contract isometrically.
Muscle contraction can also
be concentric or eccentric.
Concentric muscle
contraction — the muscle
shortens whilst contracting.
©Pete Saloutos
Eccentric muscle
contraction — the muscle
lengthens whilst contracting.
Explaining the results
Muscle size and performance
• The larger a muscle the more
force it can produce so it
won’t tire as quickly.
• For endurance activities
muscles need to work for long
periods of time but usually
without a lot of force so
muscles tend to be smaller.
Explaining the results
Why are lower body muscles stronger than
upper body muscles?
• We use our lower body muscles more in
everyday activities.
• Upper body muscles are usually only stressed
during specific activities or sports.
• Taller people tend to have:
• longer legs which make test exercises
(press-ups) harder
• a greater volume of muscle
• longer arms (further away from ground).
Explaining the results
Why are some people better at power events
compared to endurance events?
A person with a greater percentage of:
• fast-twitch muscle fibres is more suited to power
and speed activities such as the vertical jump test.
• slow-twitch muscle fibres is more suited to
endurance activities.
Students who participate in sports that need both
power and endurance may perform well in both
type of activities.
Explaining the results
Why does fatiguing one set of muscles not affect
the performance of another set of muscles?
• A muscle becomes fatigued due to:
• the build up of waste products e.g. lactic acid
• the depletion of energy sources (glycogen).
These effects are localised to the working
muscles so do not affect the performance
of different sets of muscles.
Your results
Can you do more press-ups than squats in
one minute? Is this true for everyone?
Upload your results for the
number of press-ups and
squats you performed in
Experiment B to the In the Zone
‘Live Data Zone’ and see how
you compare to other students
across the UK.
Visit www.getinthezone.org.uk/livedatazone.
Your results
How do muscles affect sporting performance?
Use data from the ‘Live Data Zone’ to help you
answer the questions below.
1 Describe the trends in the national data for upper
body strength compared to lower body strength.
2 Suggest why some people have greater upper
body strength compared to others.
3 What activities and sports are upper body strength
important for?
Your results
How do muscles affect
sporting performance?
Discuss how muscles
impact upon sporting
performance.
Use your results from
the muscle size, power
and endurance tests
and muscle fatigue
experiments.
Improving performance
Sports physiotherapists such
as Ian Gatt carry out strength
tests, like those you have
performed, on the injured
athletes they work with. They
select exercises to strengthen
selected muscles to help with
rehabilitation.
©Ian Gatt
Ian Gatt,
sports physiotherapist,
English Institute of Sport
When antagonistic muscle pairs are not equally
balanced in strength this can lead to injury.
Improving performance
Building muscle
Researchers no longer
recommend using weights
close to the maximum that
can be lifted to increase
muscle size.
©PCN Photography
They have found that new muscle protein
generation is greatest when using weights at
30% of the maximum an athlete can lift, until
they become exhausted.
Improving performance
Resistance training
By understanding muscles,
sportspeople can develop more
successful training programmes.
For example, resistance training
stimulates muscle growth by
breaking muscle fibres which
then grow bigger and stronger.
©Science Photo Library Ltd: Eye of Science
Research has indicated that this ability to
generate more muscle tissue remains even
after periods of inactivity.
Improving performance
Dancers train their
slow-twitch muscles
during circuit laps, doing
exercises like those you
have done, to increase
their stamina and
endurance.
©Wayne McGregor Random
Dance: Ravi Deepres
Odette Hughes,
Associate Director of
Wayne McGregor |
Random Dance
Improving performance
The brain is thought to
play a major role in
muscle fatigue.
Therefore the question
can be asked, does
endurance training
actually train the brain as
well as muscle tissue?
©F.C.G
Improving performance
Rehearsing mentally
Psychologists help athletes
to mentally rehearse a skill
or activity by imagining it in
their head.
This process has been shown
to stimulate the appropriate
muscles and help the athlete
to prepare for sporting
performance.
Simon Drane,
sports psychologist,
English Institute of
Sport
In the Zone
From strength to strength is the Ages 14–16 component of the In the
Zone schools experiments.
In the Zone is the Wellcome Trust’s major UK initiative inspired by the
2012 Olympic and Paralympic Games. It has been awarded the London
2012 Inspire Mark and is part of Get Set +, the official London 2012
education programme.
For more information about In the Zone, the ‘Live Data Zone’ and
downloadable teacher resources go to: www.getinthezone.org.uk.
In the Zone resources are, unless otherwise stated, licensed under a Creative Commons
Attribution-NonCommerical-ShareAlike 3.0 UK:England And Wales License. This means
that, unless indicated that restrictions apply, you can copy, share and adapt materials as
much as you like, as long as it is not for commercial use.
Credits
In the Zone is commissioned by the Wellcome Trust and
delivered by a consortium led by Pearson Education and
Guardian Professional
Pearson Education Consortium
Teacher and student materials produced by Pearson
Education Ltd
Illustrations by Oxford Designers and Illustrators
Author
Jennifer Stafford-Brown, Chief Examiner and Senior
Standards Verifier
Photo Shoot School – Farringdon Community College,
Farringdon, Oxfordshire
Advisors and Contributors to In the Zone
Ages 14-16 PowerPoint presentation
Simon Drane, English Institute of Sport
Ian Gatt, English Institute of Sport
Odette Hughes, Wayne McGregor | Random Dance
Picture credits
The publisher would like to thank the following for their kind
permission to reproduce their photographs:
(Key: b-bottom; c-centre; l-left; r-right; t-top)
Alamy Images: ITAR-TASS Photo Agency 10b, PCN
Photography 5, 20; Ian Gatt: 19; Getty Images: Jed
Jacobsohn 10r; Pearson Education Ltd: Jules Selmes 2;
Science Photo Library Ltd: Eye of Science 21;
Shutterstock.com: EcoPrint 10l, F.C.G 23, Pete Saloutos 11;
Wayne McGregor Random Dance: Ravi Deepres 22;
Additional images by Clark Wiseman / Studio8
Every effort has been made to trace the copyright holders and
we apologise in advance for any unintentional omissions. We
would be pleased to insert the appropriate acknowledgement in
any subsequent edition of this publication.
Where material is owned by a third party, e.g. some
photographs, certain restrictions may apply that you have to
comply with. In particular, where a copyright line is included on
a photograph you must not modify, adapt, or remove that photo
from its context.
Thanks to BBC Learning ‘Class Clips’ which feature in the Notes for Slide 6.
The website links to 3rd party material, which are used in this presentation, were correct and up-to-date at the time of
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