KINS 4200 Exam 1

Biomechanics

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

Biomechanics 2nd definition

study of human motion and forces that cause and/or result from those motions

The two branches of biomechanics are

kinematics and kinetics

Kinematics

Movement of an object or body segment without regards to forces causing the motion

Kinetics

Forces that cause the motion

Linear motion is also called

translation/translational motion

Linear motion is when

all part of the object move the same distance at the same time

Angular motion is

Motion around an axis of rotation

An axis can be ___ or ____, and _____ or ______

moving or fixed, internal or external

Angular motion is when

all parts of the object do not move through the same distance at the same time

Linear kinematics includes

linear position, linear velocity, and linear acceleration

linear velocity is

displacement over time

linear acceleration is

change in velocity over time

angular kinematics includes

angular position, angular velocity, and angular acceleration

linear kinetics example

ground reaction force

Ground reaction force is

force from foot stepping has an equal and opposite force coming back up from the ground

angular kinetics example

muscle torque

biodex is

a machine that measures force about an axis

statics

non-moving, rigid bodies in equilibrium

equilibrium is

a balanced state, no movement or movement at constant velocity

dynamics is

bodies in motion, acceleration is present

dynamics describes

motion and force that causes motion

Proximal

toward the attachment point

Distal

away from the attachment point

ipsilateral

on the same side

contralateral

on the opposite side

flexion

decreasing joint angle

extension

increasing joint angle

hyperextension

extension beyond normal range

abduction

moving away from midline

adduction

moving toward midline

rotation

internal or external

lateral flexion is for only

the head and the trunk

horizontal adduction

combination of flexion and adduction, moving horizontally toward midline

horizontal abduction

combination of extension and abduction, moving horizontally away from midline

radial flexion

moving hand towards the thumb side

ulnar flexion

moving hand towards the pinky finger side

scapula elevation

shrugging shoulders up

scapula depression

shrugging shoulders down

scapula adduction (retraction)

moving shoulders closer together from behind, opening chest up

scapula abduction (protraction)

moving shoulders closer together in front, closing chest

scapula upward rotation

moving shoulders and hands up

dorsiflexion

moving toes up toward knee

plantar flexion

pointing toes down

plantar inversion

moving arch of foot toward midline

plantar eversion

moving arch of foot away from midline

degrees of freedom

number of planes in which a joint can move

uniaxial definition

1 degree of freedom

uniaxial example

humeroulnar joint (elbow)

biaxial definition

2 degrees of freedom

biaxial example

tibiofemoral joint (knee)

triaxial definition

3 degrees of freedom

triaxial example

femoracetabular joint (hip)

plane

flat, two-dimensional surface

in which way does movement occur compared to its plane

parallel

what are the three types of planes

transverse, sagittal, and frontal

axis of rotation

point about which movement occurs

in which way does movement occur compared to its axis of rotation

perpendicular

what are the three types of axes of rotation

longitudinal, anteroposterior, mediolateral

is transverse a plane or axis of rotation

plane

is anteroposterior a plane or axis of rotation

axis of rotation

is sagittal a plane or axis of rotation

plane

is mediolateral a plane or axis of rotation

axis of rotation

is frontal a plane or axis of rotation

plane

is longitudinal a plane or axis of rotation

axis of rotation

the transverse plane goes with which axis of rotation

longitudinal

the sagittal plane goes with which axis of rotation

mediolateral

the frontal plane goes with which axis of rotation

anteroposterior

the longitudinal axis of rotation goes with which plane

transverse

the anteroposterior axis of rotation goes with which plane

frontal

the mediolateral axis of rotation goes with which plane

sagittal

The transverse plane bisects the body into ____ halves/parts

superior and inferior

The frontal plane bisects the body into _____ halves/parts

anterior and posterior

The sagittal plane bisects the body into _____ halves/parts

left and right

What movement is associated with the longitudinal axis?

trunk rotation, internal and external rotation

What movement is associated with the anteroposterior axis?

abduction and adduction

What movement is associated with the mediolateral axis?

flexion and extension

What is the gold standard for measuring kinematics?

Motion capture camera with infrared lights

Where must retroreflective markers be placed?

On anatomical landmarks

Do motion capture cameras track the joints or the retroreflective markers?

Retroreflective markers

When using motion capture cameras, the system may show a large red line. What is this?

The force vector

What is the sampling rate?

how fast the shutter opens and closes

What is the normal unit used for sampling rate

frames per second

What is another way to say frames per second

Hertz

What is a benefit of markerless motion capture

The research does not have to be done in a lab

What is an issue with markerless motion capture

Tracking software isn’t fully developed

Position

location in space

What is position measured with

Origin and frame of reference

Displacement

change in position

is displacement scalar or vector

vector

Distance

length of a path traveled

Is distance scalar or vector

scalar

Formula of displacement

Δs = s_f - s_i

velocity

displacement over time

velocity formula

= (s_f - s_i)/(t_f - t_i) = Δs/Δt

speed

distance over time

speed formula

d/t

is speed scalar or vector

scalar

is velocity scalar or vector

vector

Can velocity and speed have the same units?

yes