Studied by 6 people

0.0(0)

get a hint

hint

1

Biomechanics

study of structure and function of biological system by means of the methods of mechanics

New cards

2

Kinematics

study of motion WITHOUT regard to the forces that cause it

New cards

3

Kinetics

study of forces

New cards

4

Quantitative analysis definition and example

numerical evaluation of motion based on measurement

hip flexes X degrees, knee flexes Y degrees

New cards

5

pros/cons of quantitative analysis

pros: objective, accurate, specific cons: expensive, difficult to get data (special training and equipment required), difficult to apply, need norms

New cards

6

Qualitative analysis definition and example

non-numerical evaluation of motion based on observation

hip flexes, knees flex

New cards

7

pros/cons on qualitative analysis

pros: cheaper, time efficient cons: subjective, general, less accurate, experience changes results

New cards

8

statics is the evaluation of objects in a state of ...

evaluation of objects in a state of equilibrium - at rest or constant velocity

New cards

9

dynamics is the evaluation of objects ...

evaluation of objects that are not in a state of equilibrium - acceleration

New cards

10

Evaluating a runner at the start position would be static or dynamic?

static

New cards

11

Evaluating a runner after the start position would be static or dynamic?

dynamic

New cards

12

Scalar definition and examples

can be described by magnitude

distance, speed, mass, volume, energy

New cards

13

Vector definition and examples

can be described by magnitude and direction

displacement, velocity, acceleration, force

New cards

14

linear motion definition and example

straight or curved motion where all parts move the same distance in an equal amount of time

ball travelling after a throw

New cards

15

Angular motion definition and example

motion about an axis of rotation where regions do not move the same distance in an equal amount of time

a rotating sprinkler

New cards

16

Gait definition. What are the two primary gait patterns?

particular pattern of footfalls that are used in locomotion

walk and run

New cards

17

Describe the gait cycle events

Stance Phase (60% of the stride): Heel #1 makes contact with ground in frontward position (double support). All weight transfers to #1 (single support) as hip extends. Heel #2 makes contact with ground (double support).

Swing Phase (40% of the stride): All weight transfers to leg #2(single support). Leg #1 swings from hip extension to flexion

New cards

18

Step

process of moving one limb forward

New cards

19

stride

porcess of making one step with each foot

New cards

20

stride time

time it takes to complete one stride

New cards

21

stride length

distance between heel strikes of the same foot

New cards

22

stride velocity

vector so includes changes in direction

stride length/stride time

New cards

23

walking speed

scalar

distance/time

New cards

24

stride cadence (this is a frequency)

1/stride time

New cards

25

If time decreases what happens to stride velocity and walking speed?

increases

New cards

26

What is the relationship between stride velocity and stride length, and stride velocity and cadence? What does this relationship show?

There is a linear relationship (increase stride length = increase stride velocity, increase cadence = increase stride velocity). This shows the preferred speed-step length relationship where the pace chosen is the pace with the least metabolic cost

New cards

27

What happens to stride length and cadence as velocity increases during running?

The linear relationship held at walking speed does not continue. Stride length plateaus and cadence increases

New cards

28

What is the difference between a walk and a run?

Walk:

always one foot in contact with ground

contact pattern: 1, 2,1

Run:

an airborne phase between single supports

contact pattern: 1, 0, 1

New cards

29

What is considered to be a functional vital sign?

Walking speed. It is used to identify health issues and can predict adverse health outcomes

New cards

30

displacement

change in an objects position from initial to final location

vector = final position - initial position

New cards

31

velocity

rate of change of an objects displacement over a particular time interval

vector = displacement/time or (final position- initial position)/ (final time - initial time)

New cards

32

when velocity = 0

object not moving or object changing direction

New cards

33

Distance

total length travelled

scalar

New cards

34

when distance = displacement

object moves in straight line

New cards

35

Displacement is always _____ than or _____ to distance

less than or equal

New cards

36

speed

distance travelled over time or rate of distance travelled over time

scalar = distance/time

New cards

37

average velocity

average change in displacement over a time interval

New cards

38

instantaneous velocity

rate of change of displacement at a particular instant in time

New cards

39

what happens to displacement when velocity increases and time is constant?

displacement increases

New cards

40

What happens to displacement when time increases and velocity is constant

displacement increases

New cards

41

On a displacement over time graph, what represents velocity? A positive velocity is indicated by? A negative velocity is indicated by? What point on a graph would indicate that the object is changing direction? The greater the slope = ? Lesser?

slope

positive slope (line going upward)

negative slope (line going downward)

when slope changes from pos to neg or neg/pos. This indicates velocity = 0

greater velocity

lesser velocity

New cards

42

How do you calculate velocity on a displacement over time graph?

slope = rise/run

New cards

43

What motion is each segment represent?

Accelerating walking in positive direction (speeding up)

decelerating walking in positive direction (slowing down)

y = 0 stop or change in direction

Accelerating in negative direction

Decelerating in negative direction

stop

New cards

44

How is displacement calculated on a velocity vs time graph?

By taking the area of the graph and subtracting positive and negative displacements. Calculate area of a triangle = 0.5 x base x height

New cards

45

Describe the motion that each velocity vs time graph illustrates

A: slow acceleration , fast acceleration , fast deceleration, slower deceleration B: deceleration + direction, change direction, acceleration in - direction C: constant deceleration to a stop D: moving at a constant velocity

New cards

46

Acceleration

measure of the rate of change of velocity with respect to time

vector quantity

New cards

47

True or False. A change in velocity does not always indicate there is acceleration?

False. If there is a change in velocity (either magnitude or direction) then there is acceleration

New cards

48

If acceleration and velocity are in the same direction

velocity will increase

New cards

49

If acceleration and velocity are in opposite directions

velocity will decrease until the object stops or changes direction

New cards

50

What type of path do projectiles follow?

Parabolic

New cards

51

What are the vertical and horizontal accelerations of projectiles

vertical -9.81 m/s^2

horizontal 0, remains constant

New cards

52

If you kick a ball upwards at 0, 45, and 90 degrees, which will have the greatest vertical and horizontal displacement?

0

no vertical displacement

horizontal displacement but slows down from surface friction

45

less vertical displacement than kicking upwards at 90

greatest horizontal displacement

90

greatest vertical displacement

no horizontal displacement

New cards

53

Describe the time and horizontal displacement of a projectile with equal launch and landing height

time from launch to apex is equal to time from apex to landing

horizontal displacement equal from launch to apex and apex to landing

New cards

54

Describe the time and horizontal displacement of a projectile with a higher launch point than landing point

time from launch to apex will be shorter than apex to landing

horizontal displacement will be shorter from launch to apex than apex to land

New cards

55

Describe the time and horizontal displacement of a projectile with a lower launch point than landing point

time from launch to apex will be longer than apex to land

horizontal displacement from launch to apex will be longer than apex to land

New cards

56

When are velocity formulas inaccurate?

when the object is undergoing acceleration

New cards

57

If a person is not undergoing acceleration, what formula can be used and will be accurate

average velocity formulas can be used

New cards

58

frontal plane

anterior and posterior halves

New cards

59

transverse plane

inferior and superior portions

New cards

60

saggital plane

left and right sides

New cards

61

Anteroposterior axis

goes through the body from front to back

associated with frontal plane

New cards

62

Longitudinal axis

runs from top to bottom

associated with the transverse plane

New cards

63

Mediolateral axis

side to side

associated with sagittal plane

New cards

64

what are degrees of freedom? What is the max degrees of freedom? How many degrees of freedom do joints have?

number of independent movements an object can perform

max 6 degrees of freedom (3 rotations, 3 translations)

joints have 1-3 however, translation also occurs at many joints, increasing their degrees of freedom

New cards

65

Shoulder joint (Glenohumeral) - what type of joint and how many degrees of freedom?

ball and socket

3 df

New cards

66

Name the glenohumeral joint movements and what plane/axis they occur in

Flexion/extension

saggital and mediolateral

Abduction/abduction

frontal and anteroposterior

Medial and lateral rotation

transverse plane longitudinal axis

New cards

67

Superior and inferior radioulnar joints - what type of joint and how many degrees of freedom

pivot joint

1 df

New cards

68

ulnarhumeral and radiohumeral joint - what type of joint and how many degrees of freedom

hinge

1 df

New cards

69

Acetabulofemoral - what type of joint and how many df?

ball and socket

3 df

New cards

70

Describe the movements of the hip joint and what plane/axis they occur in

Flexion/extension

sagital

mediolateral

Adduction/abduction

frontal

anteroposterior

medial/lateral rotation

transverse

longitudinal

New cards

71

Knee (Tibiofemoral) joint - what type of joint and how many df?

double condyloid (modified hinge)

2 df

significant translation accompanies knee joint motion

New cards

72

Name the movements of the knee joint and what plane/axis they occur in

Flexion/extension

sagital

mediolateral

Medial/lateral rotation

transverse

longitudinal axis

New cards

73

Ankle (talocrural) joint - what type of joint and how many df?

hinge

1 df

New cards

74

ankle joint movements and plane/axis

dorsi/plantar flexion

sagital

mediolateral

New cards

75

What symbols are used for angular kinematics?

theta: angular displacement

omega: angular velocity

alpha: angular acceleration

New cards

76

Counter clockwise rotations are? Clockwise?

positive

negative

New cards

77

Angular displacement definition. Vector/scalar? Formula

differences between the initial and final orientation of a rotating object

vector = final orientation - initial orientation

New cards

78

Angular distance definition. Vector/scalar?

total of all angular changes measured following a rotating segments exact path

scalar

New cards

79

Angular displacement cannot be greater than _____, angular distance can be ______

360 degrees

any value

New cards

80

Angular velocity definition. What is it analogous to? Formula.

rate of change of angular displacement over time

analogous to linear velocity

w = (theta final - initial)/time

New cards

81

The steepness of an angle vs time graph determines the? The direction of the slope determines the?

magnitude of angular velocity

direction of angular velocity

New cards

82

On an angle vs time graph, a change in the direction of the slope indicates a?

a change in the direction of movement

New cards

83

on an angular velocity vs time graph, a change in the sign of angular velocity indicates

a change in direction of movement

New cards

84

Angular motion definition

evaluation of an objects motion around a fixed axis

all parts move through the same angle, but do not have equal linear distance

New cards

85

Name 3 techniques used to measure angular motion

Video: camera captures frames/sec

Motion capture: uses specific dots/points on body, then is input into computer

goniometry: measures the joint angle with specific instruments ex. the bendy wire

New cards

86

local reference system

axes are aligned with a segment and intersect at the joint center

New cards

87

global reference system

axes are aligned with the vertical and horizontal relative to the environment (lab)

New cards

88

How are absolute segment angles calculated?

use the trigonometric relationship of tangent

the distal end coordinate values are subtracted from the proximal end coordinate values

theta = [(y prox - y dist)/ (x prox - x dist)]

New cards

89

What is a relative joint angle? What reference system is used? Where is the vertex located?

the angle between the longitudinal axis of two segments. Defined as the angle of one segment relative to another segment

local reference system

at joint

New cards

90

Relative (joint) angle conventions - a system of lower limb conventions has been proposed for two dimensional sagittal plane rotation of the _____, _______, and ______ joints.

This system uses the _______ angles of the trunk, thigh, leg, and foot to calculate relative joint angles

With this system, it is assumed that the _____ side of the body is captured

hip, knee, and ankle

absolute

right

New cards

91

The relative hip angle is based on the absolute angles of the?

thigh and trunk

New cards

92

When the hip angle is positive, the hip is in what position? Angle = zero? Angle is negative?

flexed (because it is to the right of the vertical axis)

neutral

extended (because it is left of the vertical axis)

New cards

93

What is the formula for calculating relative hip angle

theta hip = theta thigh - theta trunk

New cards

94

The relative knee angle is based on the absolute angles of the?

thigh and leg

New cards

95

When the knee is in a flexed position the angle is? When the knee is in the extended position? Hyper-extended?

positive (extend the shin line upwards and it will end up in the positive right quadrant)

neutral

negative (extend the shin line upwards and it will be in the negative x quadrant)

New cards

96

What is the formula for calculating relative knee angle?

theta knee = theta thigh - theta leg

New cards

97

The relative ankle angle is based on the absolute angles of the

leg and foot

New cards

98

When the angle is positive, the ankle is in what position? Angle = zero? Negative?

plantarflexed

neutral position (ex standing)

dorsiflexed position

New cards

99

What is the formula for relative ankle angle?

theta ankle = theta leg - theta foot + 90

New cards

100

Define angular acceleration. It is analogous to?

rate of change of angular velocity over time

analogous to linear acceleration

New cards