PowerPoint 2 Flashcards
System definition?
Any structure or organization of related structures whose state of motion is of analytical interest (entire human, part of a person, an objected kicked or thrown).
A body or body portion that is deliberately chosen to be the focus of a particular biomechanical analysis (throwing arm, kicking leg, trunk during a lift, entire body during a vertical jump, entire runner and stride segments)
Anthropometry simple definition?
Describes the shape of the system
Anthropometry entire definition?
The discipline that studies the measurements and body segments in terms of height, weight, volume, length, breadth, proportion, inertia, and other properties related to shape, mass, and mass distribution
Inertia?
The tendency to do nothing or remain unchanged
What are the three anthropometric measures and subcategories?
-Height and weight
BMI
PI
-Somatotype
-Body segment proportion
Waist-to-hip-ratio
Crural index
What is BMI?
Body mass index = Kg/m^2
What is PI?
Ponderal index = Kg/m^3
What is the crural index?
Tibial length/femur length
What are the three somatotypes and what are their shapes?
-Endomorph (large & thick)
-Mesomorph (Average)
-Ectomorph (long & lean)
What is the anatomical position used for?
A reference point for the body
Anatomical position definition?
The person standing erect, all joints extended, feet parallel, palms facing forward, and fingers together
Superior?
Toward/closer to the head
Inferior?
Toward or closer to the feet
Anterior?
Toward the front of the body
Posterior?
Toward the rear of the body
Medial?
Position or movement toward the midline of the body
Lateral?
Position or movement away from the midline of the body
Proximal?
Closer to the attachment of a limb to the body
Distal?
Having a position farther from the attachment of the limb to the body
Superficial?
Closer to the surface of the body
Deep?
Further from the surface of the body
Cardinal plane defintion?
A plane that passes directly through the midline of the body, dividing the mass in half
What are the three cardinal planes and their definitions?
Sagittal plane-forward and backward movements occur; divides the body into left and right halves
Frontal/Coronal plane-lateral movements occur; splits the body vertically into front and back
Transverse plane-rotational movements occur; separates the body into the top and bottom
Movement occurring ____ to the plane it occurs in is described as having moved in that plane?
Parallel
Axis of rotation?
A line that is perpendicular to one of the described planes
Mediolateral axis?
Passes horizontally side to side and perpendicular to the sagittal plane
Anteroposterior axis?
Runs horizontally front to back and perpendicular to the frontal plane
Superioferior axis?
Passes up and down and perpendicular to the transverse plane
What are the three axes?
-Mediolateral axis
-Anteroposterior axis
-Superoinferior axis
Center of mass?
The point at the intersection of the three cardinal planes that represents the average location of a system’s mass
What term is the term Center of Mass synonymous with and why?
It is synonymous with the Center of Gravity because gravitational pull is concentrated at the Center of Mass
What are the five movements in the sagittal plane?
-Flexion
-Extension
-Hyperextension
-Dorsiflexion
-Plantar flexion
What are the seven movements in the frontal plane?
-Abduction
-Adduction
-Elevation and depression of the scapula
-Upward and downward rotation of the scapula
-Eversion
-Inversion
-Radial and ulnar deviation
What are the seven movements of the transverse plane?
-Rotation (left and right)
-Internal rotation
-External rotation
-Protraction
-Retraction
-Pronation
-Supination
What is the cartesian coordinate system?
A frame of reference defined by an origin and two or three orthogonal axes, each passing through the origin and define on spatial demension
Orthogonal?
Involving right angles
What is the global/fixed coordinate system?
The polar coordinate system
What is the local/somatic coordinate system?
The cartesian coordinate system/3D coordinate system that uses the three dimensions of (x,y) and possibly z
Free-body diagram?
A simplified representation of the system free of the movement environment (often a stick figure or geometric model with the center of mass and points of contact with the environment depicted)
What two things are needed for a free-body diagram?
-A sketch of the object being analyzed
-Vectors representing the forces acting on it
Closed skills?
Actions performed under standard environmental conditions (nature of the task is identical each time)
Open skills?
Actions performed in a dynamic environment (unpredictable conditions change the nature of the task)
Motion?
Change in position with respect to both spatial and temporal frames of reference (change with respect to space and time)
Force?
Something that possesses the capability to cause a change in motion or shape of the system (push or pull)
No motion occurs without ____?
Force
Translation/linear movement?
Motion along an axis in which all points of the system move at the same time, in the same direction, and at the same distance with respect to the defined reference frame (center of gravity is translating such as sledding or skateboarding)
Rotation/angular movement?
Occurs when the system is restricted to moving around a fixed axis (circular path such as a merry-go-round)
General motion?
Combination of translation and rotation (most human movement is general)
What are the three types of linear motion?
-Linear
-Rectilinear
-Curvilinear
What is linear motion?
Motion along a line
What is another name for linear motion?
Translation
What is rectilinear motion?
Two objects moving parallel to each other
What is curvilinear motion?
Moving along a curved line
What is angular motion?
Rotation around a fixed axis or central line which describes a circle
Rotating segments in angular motion have the same ____ ____?
Angular displacement
Motion in most human JOINTS is ____ ____?
Angular motion
Angular motion occurs in the plane ____ in which the rotation occurs?
Perpendicular
Most human motion is ____ ____?
General motion
____ ____ + ____ ____ = general motion
Linear motion + angular motion
What is pure rotation in a joint termed?
Spin (ulna spinning on the humerus)
What is pure translation at a joint called?
Glide
What is a combination of rotation/spin and translation/glide called?
Roll (knee joint)
Descrete movement?
Definite beginning and ending points (pole vault, tennis serve, or jump)
Continuous movement?
Cycles of motion with no well-defined beginning and end (swimming, cycling, or running)
Repeated discrete movment?
May appear continues, but the body is not in position for the next repetition because of a brief recovery phase (rowing, manual wheelchair racing, or assembly line jobs)
Serial movement?
Connected discrete motions, may appear continues but motions distinctly different (triple jump or gymnastic routines)
What are the four types of movement?
-Discrete
-Continuous
-Repeated discrete
-Serial
What are the two levels of movement?
-Gross motor
-Fine motor
Gross motor movement?
Less precision with major muscle groups and large muscles (running or lifting)
Fine motor movement?
High precision and generally controlled by small muscle groups (visual tracking)
Kinetic chain?
System of linked rigid bodies subject to force application (motion at one link affects force transfer at one or more of the other links in the chain)
What is the serial/simple kinetic chain?
Each segment participates in no more than two linkages
What is the complex kinetic chain?
A segment is linked to more than two other segments
Mobility?
Total degrees of freedom in the kinetic chain
What does more mobility require?
Greater degrees of motor control
What are the four types of kinetic chains?
-Serial/simple kinetic chain
-Complex kinetic chain
-Open kinetic chain
-Closed kinetic chain
What is an open kinetic chain?
One where the most distal segment is free to move
What is the closed kinetic chain?
One where the most distal segment is stationary
What is compensatory motion?
Adaptations at normal kinetic chain links as a result of abnormal motion at another link so the task can still be accomplished
