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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