Intro to the System [1] Flashcards
What is the system?
the body or a piece of the body
- any structire or organization of related structures whose state of motion is of analytical interest
What is anthropometry?
how the body looks: describes the shape of the system
- varying body shapes and limb proportiond affect motion
think Phelps w/ long torso & Usain w/ long legs
What are the basic anthropometric measures
- height & weight
- BMI
- Somatotype (body-type)
- Waist-to-hip
- Crural index: ratio of tibia length to femur length
What are the 3 somatotypes?
- Ectomorph: skinny, fast metabolism
- Mesomorph: even distribution of body weight
- Endomorph: slower metabolism, easy gainer, carries fat easier
What is anatomical position?
a person in an upright position w/ palms facing forward
What are the 10 directional terms?
- superior
- inferior
- medial
- lateral
- proximal (close to attatchment of limb)
- distal
- anterior
- posterior
- superficial
- deep
What are the 3 cardinal planes?
- frontal: anterior/posterior
- sagittal: right/left
- transverse: superior/inferior
Since Axes run through a plane; what are the 3 axes?
- Mediolateral (frontal) axis: passes horizontally from side to side
- Anterioposterior (saggital): runs horizontally from front to back
- Superioinferior (vertical) axis: passes up and down [perpendicular to transverse plane]
What motions occur in the sagittal plane? (and around the frontal axis)
- flexion
- extension
- hyperextension
- hyperflexion
What motions occur around the frontal plane? (and around the sagittal axis)
- abduction
- adduction
- lateral flexion/bending
- ulnar & radial deviation
- inversion & eversion
What motions occur around the transverse plane? (and around the vertical axis)
- rotation
- prontation
- supination
What motions can occur in multiple planes?
- circumduction: flexion, extension, abduction, and adduction
- Pronation of the ankle
- Supination of the ankle
What are degrees of freedom and BONUS how many DF’s in a shoulder
DF’s= the # of independent ways a system can move
- movement in 2 direction and rotation around 1 axis = 3DF’s
- A shoulder has 3DF’s bc it can
1. flex/extend
2. abduct/adduct
3. rotate medial/laterally
Knee has 1, Elbow has 2, hip has 3
What is your center of mass?
The point that represents the average location of a system’s mass
- all cardinal planes pass through this point and gravitational pull is concentrated here
What is your center of gravity and line of gravity?
COG= imaginary point representing the weight center of an object, point where all the parts are exactly balanced
LOG= imaginary vertical line that passes through the COG to the ground
What are the 3 ways we classify skills?
- Discrete: movement with a definite begining and end-point
- Continuous: cycles of motion performed repeatedly w/ no well-defined begining or end
- Serial: movemnets that appear to be continuous but are really a combination of discrete motions
Describe what **repeated discrete ** is?
It has 2 distinct phases in ROWING
- at the end of the stroke the body is not in the position to begin the next stroke
- a recovery phase is necessary
Gross VS Fine Motor Skills?
- Gross: involves large muscles/groups
- Fine: controlled by small muscles/groups or single muscles
What are closed VS open skills?
Closed skills: skill performed under a standard envriomnetal condition
- basketball free-throw
Open skills: skill that must be altered bc of the changing dynamics of the activity, enviroment, or object of interest
- passing duing soccer game
Describe motion?
The change in position w/ respect to spatial and temporal frames of reference
- motion cannot occur without force
- our muscles provide force that changes the position of the joint
What are the 3 types of “movements”?
- Translational (linear motion): motion along one axis in which all points of the system move at the same time, in the same direction
- Rotation: occurs when the system is restricted to move around a fixes axis and therefore in a circular path
- General motion: combination of linear and angular (the most “human” motion)
What are the 2 types of translation (linear motions)?
- Rectilinear translation: path of the system is a straight line (ex: driving a car)
- Curvilinear translation: path f the system is a curved line (ex: how a kicked ball arcs in the air)
Examples of Arthrokinematics?
things your joins can do:
- roll: each point on a surface contacts a unique location on another
- spin: all points on one articulating surface come in contact with one point on another
- glide: (translation) a point on one surface skids over many points on the other surface
Examples of osteokinematics?
things your bones can do: flexion, extension, abd, aduct.
Explain when a Convex surface is fixed?
when convex surface is fixed, the concave surface rolls and glides in the same direction
Explain what happens when a concave surface is fixed?
When concave is fixed, the convex surface rolls and glides in the opposite direction
What is a kinetic chain?
system of linked rigid bodies subject for force application; motion at one link of the chain affects force transfer and motion at other links [ex: we can stretch our hamstring laying down farther with a bent knee]
- simple kinetic chain: each segment participates in no more than 2 linkages (knee)
- complex kinetic chain: a segment is linked to more than 2 other segments (sacrum)
Open vs Closed Kinetic Chain?
- Open: the most distal segment is free to move
- Closed: the most distal segmnet is stationary; creates less mobilitu and cannot focus on specifc muscles, but you get more power
What is a functional kinetic chain?
A complex chain; some links are OKC while others are CKC
- think sport movements like pitching
What is compensatory motion?
- adaptations at normal KC links resulting from abnormal motion at another link
- but ensures task is performed
What are the disadvantages of compensatory motion?
- requires more energy to perform task
- changes in force patterns = pain or chronic conditions
