“MOVING THROUGH EXERCISE SCIENCE”

Describe how functional anatomy and biomechanical principles relate to performing

physical activity.

ACHIEVEMENT STANDARD 2.2 (4 credits)

The A Team (Biggs/Hose)

BACK TO BASICS

SKELETAL SYSTEM

Bones are living structures with 5 functions:

protect internal organs

support the body

make blood cells

store minerals

provide for muscle attachment

IDENTIFYING BONES

Label the bones on the skeleton. Use common names and scientific names e.g. skull and cranium.

Which bones make up the:

Elbow joint?

Knee joint?

Shoulder joint?

Hip joint?The femur below has been cut to show the internal structure.

MUSCLES

Function – to cause movement

Controlled by nerves (some voluntary, some involuntary)

Contract (shorten) – which brings bones closer together, therefore for movements to occur in both directions the muscles must work together in pairs e.g. bicep & triceps, hamstrings & quadriceps.

HOW MUSCLES MOVE

Muscles are attached to two different bones by tendons. When the muscle contracts only one bone moves.

The place where the muscle is attached to the stationary bone is called the ORIGIN. The place where the muscle is attached to the moving bone is called the INSERTION.

Insertion

Origin

AGONIST/ANTAGONISTMuscles can only pull. To make a joint move in two directions, you need two muscles that can pull in opposite directions. Antagonistic muscles are pairs of muscles that work against each other. One muscle contracts (agonist, or prime mover) while the other one relaxes (antagonist) and vice versa.The origin is where the muscle joins the fixed bone. The insertion is where it joins the moving bone. On contraction, the insertion moves towards the origin.

MUSCLES FOR ENDURANCE AND POWER

Muscles are made up of fibres. All individual voluntary muscle fibresare either fast twitch or slow twitch and these are good for differentthings. Fast Twitch for Power, Slow Twitch for Endurance

Fast twitch fibres contract very quickly and very powerfully, but they get tired quickly as they run out of oxygen in under 10 seconds. They are useful for sprinting and weightlifting or other activities requiring anaerobic exercise.

Slow twitch fibres contract more slowly and with less force, but theydon't get tired as quickly and can replace some of the oxygen that isused. They are useful for jogging and endurance activities.

Everyone has a similar number of muscle fibres, but the proportion of fast twitch and slow twitch fibres that people have differ. You cannot change the amount of slow or fast twitch muscle fibres that you have.

Does this mean sprinters are born with a natural talent or trained?

QUESTIONS

What is the difference between the origin and the insertion?

Name 3 different activities that would require a high percentage of fast twitch fibres.

Name 2 different antagonistic pairs of muscles and the movements they make.

HOW MUCH DO YOU KNOW ABOUT MUSCLESAND THEIR MOVEMENTS

JOINT MOVEMENT DESCRIPTION AGONIST MUSCLES(PRIME MOVERS)

ANTAGONIST MUSCLES

ELBOW

ELBOW

KNEE

KNEE

SHOULDER

SHOULDER

SHOULDER

SHOULDER

JOINT MOVEMENT DECRIPTION AGONIST MUSCLES(PRIME MOVERS)

ANTAGONIST MUSCLES

SHOULDER

SHOULDER

ANKLE

ANKLE

TRUNK

TRUNK

HIP

HIP

JOINT MOVEMENT DESCRIPTION AGONIST MUSCLES(PRIME MOVERS)

ANTAGONIST MUSCLES

ELBOW FLEXION BENDING THE ELBOW

BICEP TRICEP

ELBOW EXTENSION STRAIGHTENING THE ELBOW

TRICEP BICEP

KNEE FLEXION BENDING AT THE KNEE JOINT

HAMSTRING QUADRICEPS

KNEE EXTENSION STRAIGHTENING AT THE KNEE

JOINT

QUADRICEPS HAMSTRING

SHOULDER EXTENSION MOVING THE ARM FORWARD IN A ROTATIONAL

MOTION

POSTERIOR DELTOIDLATISSIMUS DORSI

TRAPEZIUS

PECTRALIS MAJORANTERIOR DELTOID

SHOULDER FLEXION MOVING ARM BACK IN A

ROTATIONAL MOTION

ANTERIOR DELTIODPECTORALIS MAJOR

POSTERIOR DELTOIDLATISSIMUS DORSI

TRAPEZIUS

SHOULDER ABDUCTION MOVING ARM AWAY FROM BODY

AT SHOULDER JOINT

TRAPEZIUSDELTOID

LATISSIMUS DORSIPECTRALIS MAJOR

SHOULDER ADDUCTION MOVING ARM TOWARDS BODY

AT SHOULDER JOINT

LATISSIMUS DORSIPECTRALIS MAJOR

TRAPEZIUSDELTOID

JOINT MOVEMENT DECRIPTION AGONIST MUSCLES(PRIME MOVERS)

ANTAGONIST MUSCLES

SHOULDER EXTERNAL ROTATION

ROTATING THE SHOULDER

BACKWARDS

POSTERIOR DELTOIDTRAPEZIUM

LATISSIMUS DORSI

ANTERIOR DELTOIDPECTORALIS MAJORPECTORALIS MINOR

SHOULDER INTERNALROTATION

ROTATING THE SHOULDER FORWARDS

ANTERIOR DELTOIDPECTORALIS MAJORPECTORALIS MINOR

POSTERIOR DELTOIDTRAPEZIUM

LATISSIMUS DORSI

ANKLE DORSIFLEXION TOES ARE PULLED

UPWARDS

TIBIALIS ANTERIOR SOLEUSGASTROCNEMIUS

ANKLE PLANTARFLEXION

TOES ARE POINTED

DOWNWARDS

SOLEUSGASTROCNEMIUS

TIBIALIS ANTERIOR

TRUNK FLEXION BEND FORWARDS

RECTUS ABDOMINUS ERECTOR SPINAE

TRUNK EXTENSION LEAN BACKWARDS

ERECTOR SPINAE RECTUS ABDOMINUS

HIP FLEXION BENDING YOUR LEG AT THE HIP

JOINT

ILIOPSOAS GLUTEUS MAXIMUS

HIP EXTENSION STRAIGTENING YOUR LEG AT THE HIP JOINT

GLUTEUS MAXIMUS ILIOPSOAS

JOINTSMovement of the skeleton is helped by joints. These are particularly helpful for sporting actions and activities. These can be separated into FOUR categories of joints. Ball and Socket JointHinge JointPivot JointGliding Joint

BALL AND SOCKET

Two examples of this joint in the human body are the hip and shoulder joints.

The rounded head of one bone fits into a cup-shaped socket of another. This joint allows the greatest range of movement.

BALL AND SOCKET

HINGE JOINTTwo examples of this type of

joint include those found at the knee and elbow.

1) If you move your hand towards and away from you.

2) If you move your leg as if you were about to kick a ball.

You will find that the movement of the joint can only occur in one way (direction) just like the hinge of a door!!

GLIDING JOINT

In this type of joint, two surfaces which are flat rub against each other. These small bones can move over one another to increase flexibility of the hands for example. They are stopped from moving too far by strong ligaments.

PIVOT JOINT

This joint is made when one bone twists against another. These are found in the spine. They also allow the head to turn, raise and lower. Extremely important for keeping balance and awareness.

QUESTIONS

On the skeleton identify the joint types labelled at 2, 3 and 5. (e.g. ball and socket, gliding, hinge, pivot)

In the diagram to the right, which joint types do figures 1, 4 and 5 represent? (e.g. ball and socket, hinge etc.)

BIOMECHANICS

Biomechanics is the study of forces and their effects on the human body during movement.

We shall look at the following biomechanical principals:

Inertia

Action/reaction

Projectile Motion

Force Summation

Levers

Newton’s Laws Of Motion

Sir Isaac Newton studied the effect of the forces on movement and from his observations developed three laws of motion to explain the relationship between motion and applied force.

1st Law – the law of Inertia

Every body will remain in a state of constant motion or rest unless acted on by a force.For a body to get moving the force has to be greater than the inertia acting upon it (inertia = a bodies tendency to remain at rest. The greater the mass of the body = greater the inertia).

2nd Law – the law of Acceleration

The acceleration of an object is directly proportional to the force causing it, is in the same direction as the applied force, and is inversely proportional to the mass of the object.

3rd Law – the law of Action/Reaction

For every action there is an equal and opposite reaction.

FORCE SUMMATION

Many skills performed in sport require maximum speed or force to be generated.Some skills require maximum force to get a

result, while others require maximum speed or velocity.

In order to do this, an athlete needs to involve as many body parts as is technically

possible.

FORCE SUMMATIONTo gain maximum momentum, the force needs to be generated by: Using as many segments of the body as possible. In the correct sequence, using large muscles first

and then the smallest muscles last but fastest. With the correct timing. Through the greatest range of motion.

EXAMPLE

An athlete competing in a discuss competition would generate less force and therefore less horizontal distance, if only the arm and shoulder are used.

Another competitor using force built up from using legs, hips, back, shoulder, arm and wrist in order would throw further.

SUMMATION OF FORCES

Maximum speed is achieved by adding the speed of each segment and transferring this to the final part of the body.

The speed of the last part of the body at the moment of contact or release will determine the velocity of the implement or projectile.

When serving in tennis or hitting a tee shot in golf, at the end of the movement of body segments the accumulated speed should be transferred to the racquet or club to generate maximum speed or force.

WORKING EXAMPLE OF FORCE SUMMATION

The student is unable to produce enough force to propel the basketball to the basket.

A solution maybe the students awareness of force summation.

Eg: When performing the basketball set shot it is important that the body parts move sequentially.

Force summation is the ability to use all body segments involved to generate greater force or speed.

Firstly the basketball player needs a stable base from which to execute their shot.

The knees must flex then move to extension in order to start the movement.

The muscles involved in this actions are the hamstrings and the quadriceps.

The hamstrings initiate flexion followed by the quadriceps being the prime movers for the knee extension.

This movement continues with shoulder extension, elbow flexion and wrist extension. This moves to shoulder flexion, elbow extension and wrist flexion( prime movers included here? )

The end result is a more powerful force that can be transferred to the ball so that it travels as far as it can towards the rim.

PROJECTILE MOTION

FACTORS AFFECTING PROJECTILE MOTION

Any object released into the air is termed a projectile.

The flight path of a projectile consists of a vertical and horizontal component.

What does this mean?

PRINCIPLES THAT AFFECT PROJECTILES

Regardless of the type of object that is being released, or by what means it is being projected, they are all governed by the same principles.

1. Gravity.2. Air resistance.3. Speed of release.4. Angle of release.5. Height of release.6. Spin.

Gravity acts on a body to give it mass. The greater the weight of an object the greater the influence of gravity upon it.What is the effect of gravity on a projectile?

GRAVITY

AIR RESISTANCE

There are several key factors that bring air resistance into play.

1. The larger the surface area, the more air resistance will affect the object.

2. If the surface is rough then air resistance will be greater.

3. Speed. As speed increases, so does air resistance. (Think of the space shuttle)

4. Mass. The smaller the mass (lighter the object) the more air resistance will affect it.

SPEED OF RELEASE

Generally, the greater the speed of release, the greater the distance gained.

In many game situations this is a factor that must be under constant control.

Can you give me an example?

ANGLE OF RELEASE

For any given speed of release, the optimum angle of release is always 45 degrees.

Is this the case in many sports? Why?

What would happen if the angle of release were to high for a given activity?

Poor distance gained

What would happen if the angle of release were too low for a given activity

Poor flight time and possibly poor distance.

HEIGHT OF RELEASE

The inter-relationship between height of release and angle of release is important to consider.The inter-relationship between height of release and angle of release is important to consider.

The reason behind this can be summarized as follows

As the height of release increases, the angle of release decreases.

As the height of release decreases, the angle of release increases.

PROJECTILE JET PLANES

Make a paper jet plane.When throwing jet plane, manipulate projectile variables to achieve maximum distance.E.g. throw from different heights – standing, sitting on your knees, standing on a chair.Use fast and slow hand speeds.Try different angles of release.

SPIN

Consider a game of Tennis. What happens to the distance achieved with a topspin shot compared to one with backspin?

A topspin shot gives poorer distance compared to backspin.

SOOOO……..

This leads us to the following two principles with respect to projectiles

and spin.1. Range is decreased with topspin.2. Range is increased with backspin.

WHY?

PRACTICAL EXAMPLE

Question?How is this biomechanical principle applied to the overhead serve in volleyball. Where can I see this being applied?

ANSWER

Firstly the speed or the force that the ball is struck/released at is important. The speed at which the ball is struck will determine how far the ball will travel. The striking force must be sufficient enough to allow the ball to cross the net but not enough to mean the ball goes out of play.

The height of release also influences the horizontal distance covered, too high and the ball may go to far, too low and the ball may strike the net. The angle is also important in conjunction with this. The angle and height of release must be judged correctly in order that the serve is successful. Spin can also be applied in order to make the ball dip after the net-making it harder for teams to return.

A lever is used when you want to apply more force.Most levers have three clearly identified parts:

1. THE FULCRUM The pivot point around which the movement happens. In the body this is usually the joint.

2.THE LOADThe weight that needs to be moved.

3.THE FORCEThe place where the force is applied. In the body

this is the effort produced by the muscles contracting .

LEVERS

CLASSES OF LEVERS

There are three classes of lever.Not surprisingly they are called:

FIRST CLASSSECOND CLASSTHIRD CLASS

First class levers can help to either increase force or generate more speed depending on the position of the fulcrum.Second class levers allow more force to be produced because the effort ,or force arm ,is longer than the resistance arm.Third class levers generate speed rather than force.

LEVERS IN SPORT

In many sports the equipment you use act as an extension of the levers in your body and helps to generate greater force or sped. Two good examples of levers used in sport can be seen in rowing or golf.

REVISION ACTIVITY

Copy down the following grid into your book/notes.

Using the pictorial sequence of the long jumper fill in the grid.

FRAME JOINT MOVEMENT AGONIST ANTAGONIST

A-B Left Elbow

1. 1.

A-E Left Knee 1. 1.

A-C Right Shoulder

1. 2.

3.

1. 2.

A-E Left & Right Shoulder

1.2.

1.2.

A-C Right Knee

1. 1.

F-G Right Ankle

1.2.

1.

REVISION ACTIVITY

Use the sequence of the long jumper to fill in the grid.

FRAME JOINT MOVEMENT AGONIST ANTAGONIST

A-B Left Elbow flexion biceps triceps

A-D Left Knee flexion hamstrings quadriceps

A-C Right Shoulder extension Posterior deltoid Latissimus dorsiTrapezius

Anterior deltoidPectoralis major

A-E Left & Right Shoulder

abduction Trapezius Deltoid

Latissimus dorsi Pectoralis major

A-C Right Knee extension quadriceps hamstrings

F-G Right Ankle Plantar flexion soleusgastrocnemius

Tibialis anterior

A-B Right Hip Flexion iliopsoas gluteals

E-F Trunk Flexion Abdominals Erector spinae

HOW ANATOMICAL AND BIOMECHANICAL

PRINCIPLES ARE INTERRELATED

Study the high jump action shown in the diagram and use it to help you list four biomechanical principles and related anatomical concepts which are important to the performance of this throw.

On your own sheet of paper, explain in detail how the anatomical and biomechanical principles you have listed above are interrelated and how they contribute to the performance of an effective high jump.

Important points to consider:

You should explain how the anatomical and biomechanical principles work together to achieve optimal performance for the high jump action pictured.

Break the skill down into parts.

Show how the key principles work together to produce the movement and the importance of each principle in performing

an effective jump.