Biomechanics Flashcards
(81 cards)
1
Q
Define articulating bones
A
The bones that form a joint
2
Q
What type of joint is the shoulder?
A
Ball and socket
3
Q
What type of joint is the elbow?
A
Hinge
4
Q
What type of joint is the hip?
A
Ball and socket
5
Q
What type of joint is the knee?
A
Hinge
6
Q
What type of joint is the ankle?
A
Hinge
7
Q
What type of joint is the neck?
A
Pivot
8
Q
How many articulating bones from the neck?
A
2
9
Q
Name the articulating bones of the neck
A
Atlas and axis
10
Q
How many articulating bones form the shoulder?
A
2
11
Q
Name the articulating bones of the shoulder
A
Humerus and scapula
12
Q
Name the articulating bones of the elbow
A
Humerus, ulna and radius
13
Q
Name the articulating bones of the hip
A
Pelvis and femur
14
Q
Name the articulating bones of the knee
A
Femur and tibia
15
Q
Name the articulating bones of the ankle
A
Talus, tibia and fibula
16
Q
Define the term agonist
A
Prime mover - the muscles that cause a movement
17
Q
Define the term antagonist
A
The muscle that works against the agonist to help produce a co-ordinated movement
18
Q
Define the term fixator
A
Muscles that stabilise the origin so that antagonists can work effectively
19
Q
Define the term synergist
A
A muscle that works together with another muscles to generate movement
20
Q
Name 3 types of muscle contraction
A
- Concentric
- Eccentric
- Isometric
21
Q
Define concentric contraction
A
The muscle shortens as it contracts
22
Q
Define the term eccentric contraction
A
The muscle lengthens as it contracts
23
Q
Define the term isometric contraction
A
The muscle contracts with no movement
24
Q
Which movements can be used at the elbow?
A
Flexion and extension
25
Which movements can be used at the knee?
Flexion and extension
26
Which movements can be used at the ankle
Plantar flexion and dorsi flexion
27
What is the agonist at the knee in the eccentric phase of a squat?
Quadriceps
28
What is the agonist at the knee in the concentric phase of a squat?
Quadriceps
29
What is the agonist at the elbow in the eccentric phase of a bicep curl?
Biceps
30
Identify the plane and axis a shot putter moves through when completing their throw
Sagittal plane/transverse axis
31
Identify the plane and axis of motion at the shoulder in the upwards phase of a press up
Transverse plane/longitudinal axis
32
Identify the plane and axis of movement at the shoulder as a performer plays a forehand shot in tennis
Transverse plane/longitudinal axis
33
During sprinting, flexion occurs at the hip.
Identify which plane and about which axis hip flexion occurs.
Sagittal plane/transverse axis
34
How many lever systems are there
3
35
During which movement does the 1st class lever system occur?
Elbow extension
36
At which part of the body do we see a 2nd class level system?
The ankle
37
How is a fulcrum represented when drawing a lever system?
Traingle
38
How is a resistance represented when drawing a lever system?
Rectangle
39
How is effort represented when drawing a lever system?
Arrow
40
In a first class lever system, what is drawn in the centre?
Triangle (fulcrum)
41
In a second class lever system, what is drawn in the centre?
Rectangle (resistance)
42
In a third class lever system, what is drawn in the centre?
Arrow (effort)
43
Identify two advantages of a second class lever system
* The effort arm is longer than the resistance arm.
* This allows the performer to generate a lot of force with minimal effort.
* Beneficial when jumping as high as possible during a high jump.
44
Identify 2 disadvantages of a second class lever system
* The resistance arm is shorter than the effort arm.
* This means there is a short range of movement.
45
Identify two advantages of a third class lever system
* The resistance arm is longer than the effort arm.
* This allows for a large range of movement.
* This also allows movements to occur faster, which helps build momentum.
* This means that a long jumper can lift their legs higher during the flight phase and can also build more momentum within the run up.
46
Identify two disadvantages of a third class lever system
* The effort arm is shorter than the resistance arm.
* This means it requires a large amount of effort to produce force;
* Which could cause fatigue.
47
Define displacement and state its unit of measurement
The shortest straight line distance between 2 points
Metres (m)
48
Define velocity and state its unit of measurement
The rate in change of displacement
Metres per second (m/s)
49
How is velocity calculated?
Displacement/time
50
Define acceleration and state its unit of measurement
The rate a body changes from one velocity to another
m/s2
51
How is acceleration calculated?
Final velocity - initial velocity/time
52
Define momentum and state its unit of measurement
Mass x velocity
Kilogram metres per second (KGM/S)
53
Define weight and state its unit of measurement
The amount of force exerted by gravity on an object
Newtons (N)
54
How is weight calculated?
Mass (kg) x gravity (9.8)
55
Name Newton's first law of motion
Law of inertia
56
Explain Newton's first law of moition
* The performer will remain stationary until an external force Is applied
* The performer will travel with a constant velocity until another force is applied
* External force is applied by the performer’s muscles
57
Name Newton's second law of motion
Law of acceleration
58
Explain Newton's second law of motion
The rate of change of momentum of a body is directly proportional to the force causing it and the change takes place in the direction in which forces the act
59
Name Newton's third law of motion
The law of action-reaction
60
Explain Newton's third law of motion
To every action there is an equal and opposite reaction
61
Define stability
The ability to maintain a centre of mass over a base of supprot
62
Name 3 factors that affect stability
1. Height of centre of mass
2. Size of base of support
3. Line of gravity
4. Mass
63
How does height of centre of mass effect stability?
The lower the centre of mass, the more stable a performer
64
How does the size of base of support effect a performer's stability?
The wider the base of support, the more stable the performer
65
How does line of gravity effect a performer's stability?
The closer the line of gravity to base of support, the grater the stability
66
How does mass effect a performer's stability?
The greater the mass of the object/performer, the greater the stability
67
Define impulse
Force x Time
68
Explain the forces of an impulse at the start of a 100m race
* Small Negative (Landing)force
* Large Positive (Push off) Force
* Net force is Positive
* Causes performer to accelerate
69
Explain the forces of an impulse during a 100m race
Both Negative landing force and positive push of force are equal
Net force is 0
Performer will travel at a constant velocity.
70
Explain the forces of an impulse during the end part of a 100m race
* Large negative landing force.
* Small positive push off force.
* Net force is negative.
* Performer will decelerate.
71
Define moment of inertia
The spread of mass from the axis of rotation
72
Define angular velocity
Speed of rotation
73
If a performer increase moment of inertia, what happens to angular velocity?
Decreases
74
How can an increase in moment of inertia be achieved?
Spreading limbs away from the body
75
If a performer decreases moment of inertia, what happens to angular velocity?
Increases
76
How can a decrease in moment of inertia be achieved?
Bringing limbs towards the body
77
How can angular momentum be calculated?
Moment of inertia x Angular velocity
78
Angular momentum always...
remains constant
79
Identify 3 factors that effect flight path
1. Height of release
2. Angle of relase
3. Force of release
80
Define drage
A force that happens in the opposite direction to motion
81
Name 2 forms of drag
1. Form drag
2. Skin drag
