This compulsory module examines the scientific foundations of human movement. In this module, students explore how the body moves and why it moves in particular ways. Students focus on the relationships between anatomy, physiology, fitness, biomechanics and efficient human movement.

2. 1) How do the musculoskeletal and cardiorespiratory
systems of the body influence and respond to
movement?
2) What is the relationship between physical fitness,
training and movement efficiency?
3) How do biomechanical principles influence
movement?

4. Tell me what are the four functions of the skeletal
system?
1) It Supports the organs and tissues of the body. Without this support
they would collapse under their own weight.
2) It provides Protection for internal organs. For example, the cranium
protects the brain; the thorax protects the heart and lungs.
3) It provides a base for the attachment of muscles and so allows
Movement with the bones acting as levers.
4) The bones are a source of supply of blood cells and a store for
minerals required for the body to function. For example, red and white
blood cells are produced in the bone marrow, which is found in the middle
of bones.

5. Label the skeletal system
ACTIVITY ONE – BONE HUNT Hidden around the classroom are the
bones of body – can you find them?
ACTIVITY TWO - SKELETAL JIGSAW As a group can you assemble the
skeletal system correctly?
LABEL THE SKELETON Using the labels provided – How many bones
can you correctly name?
HOW MANY DID YOU GET RIGHT? Check with Charlie (Classroom
skeleton)

6. What are the main types of bones?
1) Long bones are longer than they are wide, the function as levers. For
example…
2) Short bones have a short axis and are found in small spaces such as
the wrist. They serve to transfer forces. For example…
3) Flat bones have a broad surface and serve as places of attachment for
muscles and to protect vital organs. For example…

7. What are the main types of bones?
4) Irregular bones do not fall into any category due to their non-uniform
shape. Primarily consist of cancellous bone, with a thin outer layer of
compact bone. For example…
5) Sesamoid bones usually short and irregular bones, imbedded in a
tendon where it passes over a joint which serves to protect the tendon. For
example…

8. When referencing the anatomy, directional terms are used to identify the
location of bones.
Anatomical position: a reference position where the subject is standing erect,
facing front on and with palms facing forward.
1. Superior — towards the head; for example, the chest is superior
to the hips
2. Inferior — towards the feet; for example, the foot is inferior to
the leg
3. Anterior — towards the front; for example, the breast is on the
anterior chest wall
4. Posterior — towards the back; for example, the backbone is
posterior to the heart
5. Medial — towards the midline of the body; for example, the
big toe is on the medial side of the foot
6. Lateral — towards the side of the body; for example, the little toe is on the
lateral side of the foot
7. Proximal — towards the body’s mass; for example, the shoulder is proximal
to the elbow
8. Distal — away from the body’s mass; for example, the elbow is distal to the
shoulder.
Anatomical Reference: Directional Terms

9. Joints occur where one or more bones meet. Joints can be fixed, such as the rib
cage, or they can be more moveable such as in the elbow. Joints are classified
according to their degree or movement. Joints may be classified as:
- Fibrous or immovable
- Cartilaginous or slightly moveable
- Synovial or freely moveable
Fibrous joints occur where bone ends are joined by strong, short bands or fibrous
tissue such as in the skull. This type of joint does not allow any movement to occur.
Cartilaginous joints is where the bones are separated by a disc or plate made up of
tough fibrous cartilage. For example the joints of the vertebrae or spine are
separated by this tissue thus causing limited movement.
Synovial joints allow for a range of movement. These include hinge joints (knee and
elbow) and ball and socket joints (hip and shoulders). Synovial joints are made
possible with the use of tendons, ligaments, cartilage, and synovial fluid.

11. What Connects these
Joints?
Ligaments are fibrous bands that
connect bones to bones. These maintain
stability in the joint.
Tendons are tough inelastic cords that
attach muscles to bones. These further
strengthen the joint and allow the joint to
move.
Cartilage is a smooth shiny surface on
the bones which allows them to glide
across each other freely.
Synovial Fluid is a lubricant that keeps
the joints moist and nourishes the
cartilage to enable easy movement
Hyaline cartilage while synovial fluid
acts as a cushion between articulating
surfaces of the bones, they are also
covered with a layer of smooth, shiny
cartilage that allows bones to move
freely over each other. Thicker in leg
joints, where there is greater weight
bearing

12. USING THE A3 RESOURCE, SEE HOW MANY OF THE MUSCLES YOU CAN
LABEL ON YOUR SHEET

13. Muscle Relationships
Agonist
An agonist or prime mover is the muscle causing the major action. There are
agonists for all movable joints and usually more than one is involved in a
particular joint movement.
Antagonist
An antagonist is a muscle that must relax and lengthen to allow the agonist to
contract, thus helping to control an action. The agonist works as a pair with
the antagonist muscle. The two roles are interchangeable depending on the
direction of the movement.
Stabiliser
Stabiliser or fixator muscles act at a joint to stabilise it, giving the muscles a fixed
base. The muscle shortens very little during its contraction, causing minimal
movement. This permits the action to be carried out correctly and allows other
joints to work more effectively. For example, in a dynamic movement such as
throwing, while some shoulder muscles serve to propel the object, others act
as stabilisers to allow the efficient working of the elbow joint and to reduce the
possibility of damage to the joints.

14. Q: In ‘leg movement’ name
the antagonist and the
agonist muscle?

16. Types of muscle contractions
When a muscle is stimulated, it contracts. This may happen in a number of
ways. There are three principal types of muscle contraction — concentric,
eccentric and isometric.
Concentric
A concentric contraction is the most common type of muscular
contraction. During this contraction, the muscle shortens, causing
movement at the joint. Examples of concentric contractions are the
contraction of the rectus abdominis to raise the trunk during a sit-up, or the
biceps contracting to lift a weight.

17. Types of muscle contractions
Eccentric
An eccentric contraction occurs when the muscle lengthens while under
tension. The action often happens with the assistance of gravity. Examples
of eccentric contractions are the rectus abdominis extending to gradually
lower the trunk during the downward action of a sit-up, or the biceps
muscle fibres lengthening as the weight is returned to its original position

18. Types of muscle contractions
Isometric
An isometric contraction occurs when the muscle fibres are activated and
develop force, but the muscle length does not change; that is, movement
does not occur. Isometric contractions are commonly seen in attempted
movements where a resistance cannot be overcome. Examples are a
weight-lifter trying to lift a weight that cannot be moved, or a person
pushing against a wall. In each case, the effort is being made, but the
muscle length does not change because the resistance is too great.

19. Types of muscle contractions
Examples of Isometric

20. Activity – Complete the table
Do for homework – Application Page 145

21. Activity – Complete the mind map to answer: How does the
body’s muscoskeletal system influence and respond to
movement?
Do for homework – Inquiry Page 145

22. aA

23. Respiration is the process by which the body takes
oxygen in and removes carbon dioxide
Every cell in our body needs a constant supply of oxygen (O2) and food to
maintain life and to keep the body operating effectively.
Respiration is a process that occurs in practically all living cells. It uses oxygen
as a vital ingredient to free energy from food and can be characterised by the
following equation:
This process is made possible through the respiratory system that facilitates the
exchange of gases between the air we breathe and our blood. The respiratory
system acts to bring about this essential exchange of gases (CO2 and O2) through
breathing; the movement of air in and out of the lungs.

25. The parts of the respiratory system and their functions
1) Oxygen enters the body through the mouth or nose. Through the nasal
cavities the air is warmed, moistened and filtered for any foreign material
2) The pharynx serves as a common passage for air to the trachea. It
leads from the nasal cavity to the larynx (voice box), located at the
beginning of the trachea
3) Trachea is a hollow tube, strengthened by rings of cartilage. After
entering the chest cavity or thorax, the trachea divides into a right and left
bronchus (bronchial tube), which lead to the right and left lung.
4) The inner lining of the air passages, produces mucus that catches and
holds dirt and germs. It is also covered in microscopic hairs (cilia) that
remove dirt, irritants and mucus through steady, rhythmic movements

26. Lung Function
5) Lungs consist of two bag-like organs, situated on either side of the
heart and enclosed in the thoracic cavity by the ribs at the side and
sternum at the front, vetebral column at back and diaphragm below.
The light, soft lung tissue is compressed and folded like a sponge and is
composed of tiny air pockets
6) The right and left bronchi that deliver air to the lungs divide into a
number of branches or bronchioles within each lung. These bronchioles
branch many times, eventually terminating in clusters of tiny air sacs called
alveoli (singular-alveolus). The walls of the alveoli are extremely thin, with
a network of capillaries (tiny vessels carrying blood) surrounding each like
a string bag. This is where oxygen from the air we breathe is exchanged
for carbon dioxide from our bloodstream.

27. Lung Function
Inspiration = breathing in
Expiration = breathing out
During inspiration
Diaphragm contracts and flattens, external intercostal muscles (between
ribs) lift ribs outwards and upwards. This movement increases volume in
chest cavity and pulls the walls of lungs outwards, which in turn
decreases the air pressure within lungs. In response to this, air from
outside the body rushes into lungs through air passages.
During expiration
Diaphragm relaxes and moves upwards, intercostal muscles allow ribs
to return to their resting position. Volume of chest cavity has decreased,
which increases the air pressure inside lungs. Air is consequently forced
out to make pressure inside and outside the lungs about equal.

29. Exchange of gases
During Inspiration, alveoli are supplied with air high in oxygen and low in carbon
dioxide. However, blood in capillaries arriving at the alveoli is low in oxygen and high
in carbon dioxide. Different concentrations of oxygen and carbon dioxide result
between the blood and air result in a pressure difference.
Gases such as oxygen and carbon dioxide move from areas of high concentration or
pressure to areas of low concentration or pressure. Oxygen, therefore, moves from
the air in the alveoli across the alveolar–capillary wall into the blood, where it
attaches itself to haemoglobin in the red blood cells. At the same time, carbon
dioxide is unloaded from the blood into the alveoli across the alveolar–capillary wall
to be breathed out. This two-way diffusion is known as the exchange of gases (or
gaseous exchange).

30. Exchange of gases, using the same principle,
occurs between blood in the capillaries of the
arterial system and the cells of the body; for
example, the muscle cells. Here, oxygen is
unloaded to the cells while carbon dioxide resulting
from cell metabolism is given up to the blood.
Blood that is high in carbon dioxide content
(deoxygenated blood) is carried back to the lungs
where it unloads carbon dioxide.

31. Effect of physical activity on respiration
1) Rate and depth of breathing increase moderately, even before
exercise begins, as body’s nervous activity is increased in anticipation of
exercise
2) Once exercise starts, the rate and depth of breathing increase
rapidly. This is thought to be related to stimulation of the sensory
receptors in the body’s joints as a result of movement. Further increases
during exercise result mainly from increased concentration of carbon
dioxide in the blood, which triggers greater respiratory activity.
3) Increase in rate (frequency) and depth (tidal volume) of breathing
provide greater ventilation and occur, generally in proportion to
increases in exercise effort.

32. Components of the blood
http://prezi.com/jk1e0tbot9c2/?utm_campaign=share&utm_medium=copy

33. Structure and function of the heart, arteries, veins and
capillaries.
Beats70timesperminuteatrest
In one day pumps 12000 litres of blood
Atria: the upper thin-
walled chambers that
receive blood coming
back to the heart
Ventricles: the lower,
thick-walled chambers
that pump blood from the
heart to the body.

34. Structure and function of the heart, arteries, veins and
capillaries.
Beats70timesperminuteatrest
In one day pumps 12000 litres of blood
Atria: the upper thin-
walled chambers that
receive blood coming
back to the heart
Ventricles: the lower,
thick-walled chambers
that pump blood from the
heart to the body.

35. Action of the heart
The heart is able to receive and pump blood through a process called the
cardiac cycle. The cardiac cycle consists of the:
Diastole (relaxation of filling) phase: Muscles of both atria and ventricles
relax. Blood returning from lungs and body, flows in to fill both atria and
ventricles in preparation for systole (contraction)
Systole (contraction or pumping) phase: The atria contracts to further
fill ventricles. The ventricles then contract and push blood under pressure
to the lungs and all parts of the body. As they contract, the rising pressure
in the ventricles closes the atrioventricular valves (between atrium and
ventricle) and opens the valves in the arteries leaving the heart (aorta and
pulmonary artery).

36. Blood Vessels
Arteries: are blood vessels that carry blood away from the heart
Capillaries: are the smallest blood vessels. They function to exchange
oxygen and nutrients for waste.
http://www.youtube.com/watch?v=CjNKbL_-cwA&feature=related

37. Blood Vessels
Veins: carry deoxygenated blood from the body tissues back to the right
atrium. Pulmonary veins from the lungs differ in that they carry oxygenated
blood to the left atrium.

38. Pulmonary and systemic circulation
Pulmonary Circulation: is the flow of blood from the heart to the lungs
and back to the heart. The right side receives venous blood that is low in
oxygen content (deoxygenated) from all parts of the body and pumps it to
the lungs.
Systemic circulation: is the flow of blood from the heart to the body tissue
and back to the heart. The left side of the heart reives blood high in oxygen
content (oxygenated) from the lungs and pumps it around the body

39. What is blood pressure?
Blood pressure is the force exerted by the blood on the walls of the arteries. It is
measured at two points during the beating of the heart.
Systolic Pressure: is the highest (peak) pressure recorded when blood is forced
into the arteries during contraction of the left ventricle (systole)
Diastolic Pressure: is the minimum or lowest pressure recorded when the heart is
relaxing and filling (diastole)
Blood pressure is measured in millimetres of mercury by an inflatable cuff
wrapped around your upper arm. This is called a Sphygmomanometer.
The “normal” blood pressure range is 120/80. 120 is the systolic pressure
(contraction) and the 80 is the diastolic pressure (relaxing & filling)

40. What impacts blood pressure?
Blood pressure generally reflects the quality of blood being pushed out of the heart
(cardiac output) and the ease of difficulty that blood encounters passing through
arteries (resistance to flow). It can be affected by:
•Cardiac output: increase in cardiac output = increase in blood pressure
•Volume of blood in circulation: water retention (salt intake is high) increases
BP; blood loss decreases blood pressure.
•Resistance to blood flow: viscosity (stickiness) of blood increases BP as
resistance increases, such as during dehydration. Narrowing of blood vessels due
to fatty deposits affect blood flow.
•Venous return as it impacts cardiac output, it similarly impacts blood pressure.
How to measure blood pressure?
http://www.youtube.com/watch?v=1IOKUhaYZHw&feature=related

42. Physical fitness is important in establishing and maintaining total body
health. Physical fitness has a number of components which contribute to
total body fitness. These components can be grouped into health related
components and skill related components.
Health Related Components are related to our personal health and can
reduce the event of lifestyle diseases occurring such as heart disease,
obesity, and diabetes. The health related components are:-
- Cardiorespiratory Endurance
- Muscular Strength
- Muscular Endurance
- Flexibility
- Body Composition

43. Health –related fitness components respond positively to physical
exercise. For example, exercise can help us lose weight, improve
muscle tone and assist in prevention of lower back pain. However,
exercise should not be considered in isolation. Other factors such
as heredity, environment, nutrition and lifestyle practices all
contribute to total body health.

44. Skill Related Components are related to sports performance and the
ability to execute activities. The skill related components are:-
- Power
- Agility
- Coordination
- Balance
- Reaction Time
- Speed
An improvement in health-related fitness components improves personal
health and lifestyle including lowering the risk of hypokinetic disease.
Hypokinetic diseases is a term given to modern lifestyle diseases
associated with inactivity.
These include condition such as: heart disease, obesity, high blood
pressure, insomnia, diabetes and depression

45. Component Definition Important in … Suitable test
Cardiorespiratory
endurance
The ability of the heart, lungs, and circulatory system
to supply oxygen and nutrients efficiently to
working muscles and remove waste products.
Endurance events such
as cycling,
triathlons, and
marathon running
Multistage fitness
test
1.6km run
Step test
Muscular strength The ability to exert force against a resistance in a
single maximal effort.
-> improves performance and reduces the risk of injury
Weightlifting,
gymnastics, rugby
Dynamometers
1 RM tests
Muscular endurance The ability to sustain or repeat a muscular effort for a
relatively long period of time.
Cycling, cross-country
running, skiing,
rowing
Sit-up test
Push-up test
Flexibility Range of motion about a joint.
-> helps prevent injury, improves posture
Most sports Sit-and-reach test
Body composition Refers to the percentage of fat as opposed to lean
body mass (bone, muscle, organs, connective
tissue).
Health and physical
performance
BMI
Skinfold tests
Power The combination of strength and speed in an explosive
action.
Running, throwing,
jumping
Standing long jump
Vertical jump
Agility The ability to change direction with speed. Team sports Illinois agility run
Coordination Smooth, well controlled movements.
-> requires good interaction between the brain and
muscles
All sports Hand wall toss
Balance The ability to maintain equilibrium while either
stationary (static) or moving (dynamic).
All activities Stork stand
Reaction time The time taken to respond to a stimulus. Starts in athletics and
swimming,
shooting
Ruler test
Speed The ability to perform body movements quickly. Sprint events, team
games
50m sprint

46. 15 minute challenge: You have 15 minutes to put together a PowerPoint
presentation on your component of fitness you have selected. Your
PowerPoint can be no longer than 4 slides. (4 SLIDES ONLY FERAH =p).
And can only go for 5 minutes.
You must cover the following areas:
1)Define component and any key terms.
2) Outline it’s importance to health/impact on body
3) Describe the fitness test
4) Outlines ratings for given fitness test (ie. What constitutes
poor/fair/average/good/excellent)
PROPS WILL BE MADE AVAILABLE FOR PRESENTATION

47. Training programs aim to develop a range of fitness and skill components.
To develop an effective training program it is necessary to identify the
correct energy pathway.
An energy pathway is a system that converts nutrients to energy for
exercise.
If we perform short sharp movements as in jumping and lifting, the body
uses the anaerobic pathway to supply energy. Anaerobic means ‘in the
absence of oxygen’.
If movements are sustained and of moderate intensity, the aerobic
pathway supplies the bulk of the energy needs. Aerobic means ‘with
oxygen”

48. Aerobic Training
Aerobic exercise refers to exercise that is dependent on oxygen utilistaion by the
body to enable muscular work.
Activity that is of low to moderate intensity and continues for 90
seconds or more is generally termed aerobic because oxygen
becomes available to the cells of working muscles for energy
generation
Walking, marathon running and the 1500 metres in swimming are examples of
activities that require a high degree of aerobic fitness.
To improve aerobic fitness we need to:
•Engage in activities that are continuous and of long duration. Cross-country
running, sand-hill running, cycling and jogging are examples of activities that
develop our aerobic energy system
•Use the FITT principle to develop an aerobic program to suit our needs. The
principle provides guidelines for individuals who aim to improve cardiorespiratory
fitness and some forms of resistance training. It ensures a program has the
quantity and quality of movement necessary to produce the desired physical
improvement.

49. Frequency
This refers to how many times per week we train.
For improvement to occur, individuals must train on at least 3 occasions per week.
This can be increased to five, but the benefit to be gained from sessions in excess
of this is minimal.
The aim is for a training session to sufficiently stress body systems, causing a
response called adaptation.
An adaptation refers to an adjustment made by the body as a result of exposure
to progressive increases in the intensity of training.
This is an adjustment made by the body as a result of exposure to progressive
increases in intensity of training. For resistance training, 3 sessions are sufficient, 4
is maximal, allowing rest days in between for muscle fibres to regenerate.

50. Intensity This refers to how hard we work during each training session or the amount of effort
required be an individual to accrue a fitness benefit.
The most accurate way of measuring intensity during aerobic exercise is by calculating your
target heart rate and using this as a guide. The target heart rate together with the area above
and below is called the target heart rate zone. When exercising, the level of intensity
needs to be sufficient to keep the heart rate within the target heart rate zone for the
required period of time.
The level of intensity is established in terms of heart rate, which is calculated
in beats per minute (bpm). There are two important steps that need to be
taken to calculate your target heart rate zone.
1. Determine your maximum heart rate. To do this, simply subtract your age
from 220. Hence, a 20-year-old person would have a maximum heart rate of
200 beats per minute.
2. Determine the percentage of your maximal heart rate relevant to your fitness. If your
fitness is poor, work at 50 to 70 per cent of your maximum heart rate. If your fitness is good,
work at 70 to 85 per cent of your maximum heart rate. If uncertain, work at the lower level
and gradually increase the level of intensity.
•For aerobic fitness we need to increase out heart rate to around 60 – 80% of our maximum
heart rate of 220 beats per minutes (less our age). This is known as the training zone and it
will mean we gain a training effect for our hearts and our lungs. To work this out, use the
following examples –
–220 minus your age (15 years) = 205 (maximum HR)
–60% of 205 = 123 beats per minute
–80% of 208 = 164 beats per minute

51. Time
•This refers to the period of time that you exercise for continuously. A base
line level of 20 minutes is needed to secure an aerobic training effect
There is little sense in exercising for periods longer than 60 minutes or to
exhaustion as this carries the risk of overtraining and the possible development of
overuse injuries (elite athletes excepted). 30–45 minutes is generally sufficient and
will depend on the intensity of exercise.

52. Type
•This refers to the type of exercise performed.
Based on factors such as areas that need improvement or type of sport. They type
of exercise should align with the type of sport or area of improvement you.
For example,
A swimmer is an Aerobic activity, requiring cardiorespiratory efficiency.
Therefore there training program should involved aerobic activities that target the
cardiorespiratory system.

53. Anaerobic means ‘in the absence of oxygen’.
In anaerobic activity, the intensity level is much higher and the effort period much
shorter than required in
aerobic activity.
In general, activity that lasts for two minutes or less and is of high intensity
is called anaerobic because muscular work takes place without oxygen
being present. Anaerobic exertion requires specialised training to generate the
adaptations necessary for muscular work without oxygen. Training enhances the
ability of muscle cells to improve their use of fuel reserves and be more efficient in
converting blood sugar to energy during intense exercise.

54. To improve anaerobic fitness, we need to:
•work hard at performing and enduring specific anaerobic movements such as lifting
weights, throwing or jumping
•practise the required movements at or close to competition speed to encourage the
correct adaptations to occur
•use activities such as interval training where periods of intense work are interspersed
with short rests to train the anaerobic system to supply sufficient fuel utilise resistance
(weight) training exercises to further develop the muscles required for the movement
•train to improve the body’s ability to recharge itself; that is, to decrease recovery time
after short periods of intense exercise
•train to improve the body’s ability to tolerate higher levels of lactic acid, a
performance use crippling substance that builds up in the muscles following intense
exercise
•gradually develop the body’s ability to utilise and/or dispose of waste that is created
by intense exercise.

55. Training programs are all about meeting the specific needs of the individual,
their chosen activity and goals.
Some sports require a high level of aerobic fitness and a general level of anaerobic
fitness while the reverse is true of others. Games such as touch football, soccer and
netball are characterised by periods of moderate intensity interspersed with periods of
high intensity.
While the amount of aerobic/anaerobic fitness varies according to the game,
it is also affected by the position of the player, each individual’s effort and their
base fitness level. The sprint in rugby, rally in tennis and man-to-man defence
in basketball are all highly demanding, causing muscles to use available fuel and then
requiring cells to find other sources for energy supply.
The change between aerobic and anaerobic energy supply is gradual rather
than abrupt. When engaged in activity, the body switches between systems
according to the intensity of exercise, with one system being predominant and the
other always working but not being the major supplier of energy. A sprint during
a touch football game requires anaerobic energy due to the instant and heavy
demands made on the muscles involved in the movement. During this period,
the aerobic system is still functioning, but is not the major energy supplier.

56. Select one of the following sports: soccer, netball, rugby league
Select a specific position: goal keeper, centre, half-back
Answer the following questions using specific examples
1) During which play/movement sequence is the aerobic system utilised?
2) During which play/movement sequence is the anaerobic system utilised?
3) Describe a movement/play sequence when both the aerobic and anaerobic
systems would be utilised?

57. Based on your given component, use Publisher to design an informative
newsletter page
You need to answer the following areas:
1)Define component, give any key terms
2)Outline calculations used
3)Describe the impact training has on the given component
Due Friday, June 1st
,2012

59. Biomechanics is the science concerned with forces and the effect of these forces on
and within the human body.
A knowledge of biomechanics helps us to:
• choose the best technique to achieve our best performance with consideration
to our body shape. For instance, an understanding of the biomechanical principles
that affect athletic movements, such as the high jump, discus throw, golf swing and
netball shot, improve the efficiency with which these movements are made. This
improves how well we perform the skill.
• reduce the risk of injury by improving the way we move
• design and use equipment that contributes to improved performance.

60. Motion is the movement of the body from one position to another
Some bodies are inanimate (non-living) such as basketballs, shot puts; whilst other
bodies are animate (living) such as golfers, footballers.
Motion itself can be divided into 3 categories:
•Linear
•Angular
•General

61. Linear motion takes place when a body and all parts connected to it travel the same
distance in the same direction and at the same speed.
The easiest way to determine if a body is experiencing linear motion is to draw a line
connecting two parts of the body; for example, the neck and hips. If the line remains
in the same position when the body moves from one position to another, the motion
is linear.

62. Angular motion the motion of a body about a fixed point or fixed axis. Angular
movement plays the dominant role because most of an athlete’s movements result
from the swinging, turning action of the athlete’s limbs as they rotate around the
joints.
Many terms are used to refer to angular motion. Movements include rotating,
spinning, swinging, circling, turning, rolling, pirouetting, somersaulting and twisting.
All of these terms indicate that an object or an athlete is turning through an angle, or
number of degrees. In sports such as gymnastics, skateboarding, basketball, diving,
figure skating, and ballet, the movements used by athletes include quarter turns (90
degrees); half turns (180 degrees); and full turns, or “revs” (revolutions), which are
multiples of 360 degrees

63. General motion a mix of linear and angular, which we simply call general motion. In
sport, a mix of linear and angular movement is most common.
Even those sport skills that require an athlete to hold a set position involve various
amounts of linear and angular motion. For example, a gymnast balancing on a beam.
In maintaining balance on the beam, the gymnast still moves, however slightly. This
movement may contain some linear motion but will be made up primarily of angular
motion occurring around the axes of the gymnast’s joints and where the gymnast’s
feet contact the beam. Perhaps the most visible combination of angular and linear
motion occurs in a wheelchair race. The swinging, repetitive angular motion of the
athlete’s arms rotates the wheels. The motion of the wheels carries both the athlete
and the chair along the track. Down the straightaway, the athlete and chair can be
moving in a linear fashion. At the same time the wheels and the athlete’s arms
exhibit angular motion

64. ;
Improving performance in activities that encompass linear motion usually focuses on
modifying or eliminating technique faults that contribute to any non-linear movements.
Excessive up and down, rotational and lateral movements are examples of faults that
erode performance directed towards achieving the shortest, most efficient pathway.
Swimmers who use an irregular arm pull that results in a zigzag movement pattern
along the pool surface are examples of poor application of linear motion.
Homework Tip: For swimmers, excessive movement increases drag which slows down
a swimmer.
But what is drag and how does a swimmer eliminate it to enhance their swimming?
Reference: http://library.thinkquest.org/06aug/02165/physics_of_swimming.htm

65. How motion is classified depends on the path followed by the moving object.
We will focus on linear motion in a range of sporting activities and apply the
principle to enhancing performance.
Velocity is equal to displacement divided by time.
Displacement is the movement of a body from one location to another in a particular
direction, or an ‘as the crow flies’ measurement.
Velocity is used for calculations where the object or person does not move in
a straight line. An example is a runner in a cross-country race. Activities to
improve speed may also relate to velocity. Improving the velocity of implements
such as javelins or arrows requires specialised training, as does improving the
performance of athletes in non-linear events such as marathons.

67. Speed is equal to the distance covered divided by the time taken to cover distance
So, if a runner runs 100m in 12 secs
Speed is important in most sports and team games. The player who can
move quickly has a distinct advantage in games such as touch football, rugby
and soccer because not only is that player difficult to catch, but he/she can use
their speed to gather opponents quickly in defence.
Much of our potential for speed is genetic and relates to the type of muscle
fibre in our bodies. However, individuals can develop their speed as a result of
training and technique improvements, the basis of which is the development
of power and efficiency of movement.

68. Momentum the quantity of motion the body possesses
Mass refers to the amount of matter in a body
The application of the principle of momentum is most significant in impact
or collision situations. The principle can be applied to certain sporting games such as
rugby league and rugby union, where collisions in the form of tackles are part of the
game. However, collisions between players in sporting events tend to exhibit different
characteristics to that of objects due to a range of factors, including:
•the mass differences of the players — in most sports, we do not see the huge
variations in mass that we find between cars, bicycles and similar objects
• elasticity — the soft tissue of the body, which includes muscle, tendons and
ligaments, absorbs much of the impact. It acts as a cushion.
• evasive skills of players which often result in the collision not being ‘head-on’.
In some cases there may be some entanglement just prior to collision, such
as a palm-off or fend. This lessens the force of impact.
The momentum described in the previous situation is called linear momentum
because the object or person is moving in a straight line.

69. There are numerous instances in sport where bodies generate momentum but
they do not travel in a straight line; for example, a diver performing a somersault
with a full twist, football kick, discus throw and golf
swing. In each of these cases, the body, part of it, or an attachment to it such as
a golf club or tennis racquet, is rotating. We call this angular momentum.
Angular momentum is the quantity of angular motion in a body or part of a body
Angular momentum is affected by:
• angular velocity For example, the distance we can hit a golf ball is determined
by the speed at which we can move the club head.
• the mass of the object. The greater the mass of the object, the more effort we
need to make to increase the angular velocity. It is relatively easy to swing
a small object such as a whistle on the end of a cord. Imagine the effort that
would be needed to swing a shot-put on a cord.
• the location of the mass in respect to the axis of rotation. With most sport
equipment, the centre of mass is located at a point where the player is able to have
control and impart considerable speed. Take baseball bats and golf clubs for
example. Here, the centre of mass is well down the shaft on both pieces of
equipment. This location enables the player to deliver force by combining
the mass of the implement at speed in a controlled manner, thereby maximising
distance.

71. ;
The centre of gravity of an object is the point at which all the weight is evenly
distributed and about which the object is balanced.
If the object is spherical, it’s centre of gravity is directly in the the centre however,
some objects used in sport are not perfectly spherical or do not have an evenly
distributed mass ie. lawn bowl. When rolled on a flat surface, the object will have a
slight ‘bias’ to where the mass has been redistributed.
In the human body, the position of the centre of gravity depends upon how the
body parts are arranged; that is, the position of the arms and legs relative to the
trunk. Because the human body is flexible and can assume a variety of positions, the
location of the centre of gravity can vary. It can even move outside the body during
certain movements.

72. ;
Varying the centre of gravity in the execution of a skill can enhance
performance. Skilled high jumpers and long jumpers both lower the centre of gravity
in the step or steps immediately preceding take-off. This enables them to propel their
body over a slightly longer vertical path than would otherwise be possible.
Static balance activities such as headstands and handstands require precise
manipulation of the centre of gravity.
Dynamic balance activities also require skilful control of the centre of gravity. In many
moving activities, such as skiing and surfing, there is a fine line between the balance
necessary for control and loss of balance resulting in a fall.

73. ;
The line of gravity is an imaginary vertical line passing through the centre of gravity
and extending to the ground. It indicates the direction that gravity is acting on the
body. When we are standing erect the line of gravity dissects the centre of gravity so
that we are perfectly balanced over our base of support.
Our base of support has a limited area. Widening our stance increases the size of the
base of support. However, rules of some sports and competitions limit the size of the
base of support; for example, the starting blocks in athletics.
The closer the line of gravity moves to the outer limits of the base of support, the less
stable we become. Movement results in a momentary state of imbalance being
created, causing the body to move in the direction of the imbalance.
In specialised sporting movements, such as the start in athletics, the precision with
which the line of gravity moves in relation to the base of support directly affects the
quantity and quality of movement.
During practice of specialised skills, athletes progressively develop a feel for the line of
gravity relative to the base of support, enabling the controlled instability required for
movement. This means that less force is required to initiate the desired movement.

74. ;
The base of support refers to an imaginary area that surrounds the outside edge of
the body when it is in contact with a surface. It affects our stability or our ability to
control equilibrium. A wide base of support is essential for stability because the centre
of gravity is located well within the boundaries.
There are many examples where athletes use the base of support to their advantage.
• The gymnast performing a pirouette has a very narrow base of support and must
work hard to ensure that their centre of gravity remains within the base.
• Wrestlers widen their base of support to prevent their opponents from moving them
into a disadvantageous position.
• Tennis players lower the centre of gravity and widen the base of support in
preparation to receive a fast serve. This enhances balance and enables the centre of
gravity to be moved in the desired direction more readily.
• Swimmers on the blocks widen their feet and move the centre of gravity forward to
improve their acceleration.
• Golfers spread their feet to at least the width of their shoulders to enhance balance
when they rotate their body during the swing.

75. ;
1) Define:
a) Force
b) Power
2) Explain the difference between an internal and external force and their impact on
movement. Give examples.

76. ;
Force (biomechanics) is the push or pull acting on a body
Internal forces are those that develop within the body; that is, by the contraction of a
muscle group causing a joint angle to decrease (for example, the contraction of the
quadriceps when kicking a football)
External forces come from outside the body and act on it in one way or another. For
example, gravity is an external force that acts to prevent objects from leaving the
ground
Internal forces External forces
Muscle contractions Gravity
Muscle tension Air resistance
Joint force/movement Water resistance
Friction

77. ;
There are two types of forces:
Applied Force are forces generated by muscles working on joints. Applied forces are
forces applied to surfaces such as a running track or to equipment such as a barbell. ;
When this happens, a similar force opposes it from outside the body. This is called a
reaction force.
Reaction Forces are equal and opposite forces exerted in response to applied forces.
The result is that the runner is able to propel his or her body along the track surface
because the applied force generated by the legs is being matched equally by the
reaction force coming from the track surface.
This is explained by Newton’s third law: ‘For every action, there is an equal and
opposite reaction’. In other words, both the runner and the track each exert a force
equal to whatever force is being applied.

78. ;
We see evidence of the application of force in all physical activity. Consider the
following examples: the high jumper, discus thrower, cricket bowler and basketball
player all exert forces when executing movement skills.

79. ;
Power (biomechanics) is the ability of muscle groups to contract at speed.
To propel the body higher as in high jumping, faster as in running, or further as in long
jumping, we need to develop power. Power is expressed by the formula
An increase in strength (force) or an increase in the speed at which muscles shorten
results in an increase in power. While an increase in both causes an increase in
overall power, the athlete must decide which component (strength or speed of
muscular contraction) is of greatest benefit.
Jumpers and runners need to focus on rapid muscular contraction while controlling the
strength aspect. This is called speed-dominated power. In contrast, the weight-lifter
needs power and must be able to lift the weight. He or she needs to develop strength-
dominated power.

80. ;
Forces exerted on the body are absorbed through the joints, which bend or flex in
response to the impact. Joint flexion helps prevent injury to surrounding tissue. With
inanimate objects, techniques have been developed to absorb their impact.
There are principles to remember with the application of force on an object:
1)The quantity of force applied to the object is important. The greater the force, the
greater is the acceleration of the object
2)If the mass of an object is increased, more force is needed to move the object
the same distance. For example, if a football becomes heavier as a result of wet
conditions, more force is required to pass or kick it.
3)Objects of greater mass require more force to move them than objects of
smaller mass. The size of the discus, javelin and shot-put is smaller for younger
students than older students. This assumes that older students have greater mass and
are thereby able to deliver more force than younger students because of their increased
size (mass) and (possibly) strength.
In many sports and activities, the body rotates about an axis. When this happens
centripetal force and centrifugal force are experienced.

81. ;
Centripetal force is a force directed towards the centre of a rotating body.
Centrifugal force is a force directed away from the centre of a rotating body.
These forces commonly occur with skills that require rotation such as the golf swing or
the hammer throw.
To manage centripetal and centrifugal forces in sporting situations it is
important to:
• begin carefully so that you learn to feel the forces as they develop
• respond gradually, trying to match the force exactly
• work on your balance so that you become comfortable leaning beyond where you
would normally be balanced
• ensure you have a firm handgrip if holding an object such as a bat or high bar
• bend your knees and ensure you have good traction if working on a track, field or
circuit.