Biomechanics Year 11 Physical Education AS 1.2 Credits: 5 Miss Sandri.

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BiomechanicsYear 11 Physical EducationAS 1.2 Credits: 5

Miss Sandri

MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY

12 13 14 15 16

19 20 21 22 23

26 27 28 29 30

CALENDAR SEPTEMBER 2013

CALENDAR AUGUST 2013

2 3 4 5 6

9 10 11 12 13

16 17 18 19

EXAM1.20pm

Study Leave

RevisionRevision

HOSE 16 x Lessons

No Lesson

No Lesson

No Lesson

No Lesson

No Lesson

Hose- Theory Hose- PracticalBIOMECANICS

Force SummationForce Summation

*Practical*

Newton’s LawsTheory

Practical- Cross Country OR Frisbee

Golf

Projectile Motion/ Leavers

Practical- Volleyball

PHYSIOLOGYSTARTS

MONDAY TUESDAY WEDNESDAY THURSDAY FRIDAY

12 13 14 15 16

19 20 21 22 23

26 27 28 29 30

CALENDAR SEPTEMBER 2013

CALENDAR AUGUST 2013

2 3 4 5 6

9 10 11 12 13

16 17 18 19

EXAM1.20pm

Study Leave

RevisionRevision

BRADLEY 14 x Lessons

No Lesson

No Lesson

No Lesson

No Lesson

Bradley- Cross Country

Bradley- AnatomyBradley- AnatomyForce

Summation/ Practical

Cross Country- No class

Stability/ Force Summation

Force Summation- Frisbee Golf

Newton's Laws of Motion

Practical Session-Volleyball

Biomechanics Revision & Intro to

PHYSIOLOGY

BiomechanicsBiomechanics is the study of forces and their effects on

the human body during movement.

Forces are the basis for all movement.

Body TypesEctomorph:

Tall and slenderVery little muscleBasketball

Mesomorph:Muscular and athleticStrength and enduranceAthletics

Endomorph: Short and high proportion of fatShort durationSwimming, sumo, power lifting

1.Balance and Stability

2.Force Summation

3.Newton’s Laws

4.Projectile Motion

5.Levers

Biomechanics

1. Balance and Stability

•Centre of Gravity (CoG)

•Base of Support (BoS)

• Line of Gravity (LoG)

Centre of Gravity• The point at which all parts of an object

are equally balanced.

• Standing up right our centre of gravity is around our navel.

• The centre of gravity changes depending upon what position the body is in.

• The centre of gravity can lie outside an object.

• Generally, the lower the COG the more stable an object will be.

Base of Support• The area within an object’s point of contact with the ground.

• Generally, the larger the area the base of support covers, the more stable an object will be.

Line of Gravity•The vertical line that passes

through the centre of gravity to the ground.

•The line of gravity is important when determining the stability of an object.

• If the line of gravity falls within an object’s base of support the object is relatively stable.

Stability Summary•COG, BOS & LOG

•Key points- to maximise stability you should…▫Lower the _____▫Increase the size of the ____▫Keep the ____ within the ____▫The _____ passes within the ____

• Lets think of some sporting examples…

COG

BOS

LOG BOS

LOG COG

2. Force Summation•To give an object momentum in activities such as throwing, kicking orstriking an object, the amount of momentum given to the object is determined by‘the sum of all forces generated by each body

part’.

Principles of Force Summation…

•Use the greatest number of body segments or muscle groups as possible.

• In the correct sequence, use large muscle groups first and then the small muscles last, but fast.

•Use the correct timing of the body segments or muscle groups.

Force Summation

• Stop the video at 7.25mins

Research Task• Collect a work sheet and follow the instructions

When finished, come back into the classroom.

Do now/ for homework:▫Using the information you have acquired surrounding force

summation, and in table 1, describe your findings and give explanations as to why the throw distance may vary. Use the principles of force summation to explain your answer.

DUE: Finished?? See me!

3. Newton’s 3 Laws of Motion•Sir Isaac NewtonExplains the relationship between the forces acting on a body and the motion of a body.

Newton’s 3 Laws of Motion

1st BOX: Key words, definition.

2nd BOX: Sports related diagram.

3rd BOX: Connecting the two.

Law 1: Inertia

Law 1: Inertia- an object remains at rest or in motion unless acted upon by an external

force.

Law 1: Inertia• Inertia is an objects resistance to change in motion.

An objects inertia is proportional to it’s weight (mass).

•The heavier the object, the more inertia it has.

•Sporting example…

Law 2: Acceleration• Law 2: Acceleration- the acceleration of an object is

dependant on the mass, size and direction of the force acting upon it.

• force = mass x acceleration [ f = m x a ]

Law 2: Acceleration•When a force is applied

to an object, it will move in the direction the force was applied.

• Depending on the size/ mass of the object, it will accelerate accordingly. ▫The smaller the object

the faster it will accelerate.

▫The larger the mass, the slower the acceleration.

Law 3: Action/Reaction

• Law 3: Action- reaction- whenever a force is

applied there is an equal and opposite reaction.

Law 3: Action/ Reaction• If an athlete exerts a force

onto the ground in order to push off, the ground will exert an equal and opposite force on the athlete, pushing them up into the air.

•Action force

•Reaction force

http://www.youtube.com/watch?v=MAm6LOUnJ80

Example- Swimming•Think about a swimmer:

a) When would Newton’s 3 laws take place?

b) How could Newton’s 3 laws of motion help their performance?

Summary: Newton’s 3 Laws of Motion•Sir Isaac NewtonExplains the relationship between the forces acting on a body and the motion of a body.

Law 1: Inertia- an object remains at rest or in motion unless acted upon by an external force.

Law 2: Acceleration- the acceleration of an object is dependant on the mass, size and direction of the force acting upon it.

Law 3: Action- reaction- whenever a force is applied there is an equal and opposite reaction.

4. Projectile Motion •Principles of Flight (Projectile Motion)

A projectile is an object upon which the only force acting is gravity (for the purposes of this unit we assume air resistance is negligible). This means that even you can be a projectile if you leave the ground!

Projectile Motion•When maximum distance is required there are 3

things that will influence the distance of the projectile.

▫Height of release.▫Speed of release. ▫Angle of release

Height of Release•For a given speed and angle of release, the greater

the height of release the greater the distance gained.

•Question 1 & 2

Speed of Release•For any given angle of release, speed of release

makes a considerable difference to the distance a projectile will travel.

•Connection to force summation.

•Question 3

Angle of Release

When throwing for distance- 45degrees is the ultimate angle.

Question 4

5. Levers• Leavers help apply force as they can move greater

loads with a set amount of force.

• Most levers have three clearly identified parts:▫ The pivot (or fulcrum)▫ The load (resistance)▫ The effort (force)

Three Types of Levers1. First Class Lever

e.g. see saw, rower, leg press etc.

Question 5

2. Second Class Lever

e.g. a wheel barrow

Question 6

Third Class Lever•The third class lever is the most applicable to sports

biomechanics. •Any instrument such as a bat, club, arm, leg etc

could be considered a third class lever.

•Question 7 & 8

Levers• Longer levers result in more speed, beneficial for

striking and throwing objects.

• Shorter levers result in greater strength, beneficial for pushing, pulling, and lifting objects.

▫Which one has more control? Try writing with your pen with your hand holding the

top of it.

•Question 9

Summary•Projectile Motion▫Height of release▫Angle of release▫Speed of release

• Levers▫First class▫Second class▫Third class (THE MOST IMPORTANT)

Longer levers= increased speed Shorter levers= greater strength