160 more like 160poo

what are some things in linear kinetics

• linear position (x,y,z,)

• linear displacement (delta, xyx) = change in linear position

• linear velocity - rate and direction of change of linear position (m/s)

• linear acceleration - rate and direction of linear velocity (m/s²)

what is gravitys constant

9.81m/s²

what is the law of acceleration

second law, net unbalance force caused by acceleration in a direction of force that is proportioned to net force and inverse proportion to its inertia

what is angular kinetics

inertia and how forces cause acceleration to be different

what is inertia

resistance to acceleration

what is the moment of inertia

• body’s rotational inertia (resistance to angular acceleration)

• depends on mass and spatial distribution to relative axis of rotation

simply - distribution of mass and where its located

what is the rotation of a freebody

a linear force that rotates around center of mass if the force is not aligned with it

what is the law of acceleration

rate of change of moment is proportional to unbalanced loads and inversely proportional to inertia

what are three deformation mechanics

viscosity

elasticity

plasticity

explain viscosity

• internal friction

• resistance to rate of deformation

• can dissipate energy with heat and sound

explain elasticity

• can return to its original shape when load is removed

explain plasticity

• deforms and has rearrangement of molecules and intermolecular bonds

• requires energy

• remains deformed

is deformation proportional

yes, it is proportional to extent or force generated by deformation

is elastic force proportional

yes elastic force is proportional to extent of deformation

if viscosity force proportional

no, force generated by viscosity is not proportional

what does flexibility do/have

• performance capacity benefits

• length of muscle generates more power

• more flexibility give more of a change to dislocate joint

• not just a health issue

how many mode of muscle activation modes are shortening velocity

4

how many mode of muscle activation modes are tension (isotonic)

1

what are the four shortening velocity modes

shortening activation - positive shortening velocity

lengthening activation - negative shortening velocity

isometric activation - zero shortening velocity

isokinetic activation - constant shortening velocity

what is isotonic muscle activation mode

activation with constant tension

what are the functions of mode activation

• accelerates with body segments - shortening muscles

• maintains constant velocity - isometric, shortening, and lengthening muscles

• decelerates body segments- lengthening muscles

how do elbow curl velocities work

goes from slow to fast to slow (going through the motion of curling)

what are the 6 independent components of degrees of freedom

• 3 orthogonal translations - x,y,z-axis

• 3 orthogonal rotaions - xy,xz,yz-planes

what is the global coordinate system (GCS)

fixed to the earth

what is the segmental coordinate system (SCS)

fixed to a segment (like a knee) and moves with segment relative to GCS

what are physiological DoF

movements in joints without injury

what are non-physiological DoF

movements in joints with injury so it constrains motion

what are accessory DoFs

have small amounts of motion

what is the ginglymi joint (with RDoF and examples)

• hinge joint

• 1 RDoF

• physiological DoF: flexion and extension

• non-physiological DoF: varus-valgus and axial rotation

• e.g. knee, elbow, IPJs (knuckles) in digits

what is a condyloid and saddle joint

• bi-hinge joints 

• 2 RDoFs

• condyloid - bi-convex/bi-concave elliptic articulation

• physiologic DoFs: flexion and extension, and adbuction-adduction

• non-physiologic DoFs: xial rotation and translations

• e.g. wrist, MCPJs (lower knuckles) in fingers, CMCJ (base of thumb)

what are trochoid joints

• barrel joints

• 1 RDoF - parallel

• physiologic DoF: pronation-supination

• non-physiologic DoF: sagittal plane and coronal plane roation

• eg. radio-ulnar joints in forearm

what are enarthroses joints

• ball and socket

• 3 RDoF

• physiologic DoF: three rotations

• non-physiologic DoF: translations

• eg. hip, GH shoulder

what three rotations does the hip joint do

• flexion and extension

• internal and external rotation

• abduction and adduction

• has a gimbal lock at 90 degree abduction

what three rotations does the gleno-humaral joint have

• horizontal ab-adduction

• internal and external rotation

• elevation

• gimbal lock in anatomical position

what the scapulo-thoracic joint do

• elevation

• protraction

• retraction

• shrug

what are the arthrodial joints

• sliding joints

• 2 TDoFs

• multi-joint unit

• eg. facet joints in spine

what are the complex joints

• multiple DoFs

• articular surfaces slightly curved

• sliding and gliding motions

• eg. tempero-mandibular joint (jaw)

what are some body shapes

• valgus

• varus

• kyphosis - primary curve

• lordosis - secondary curve

• scoliosis

what are some constraints of movement

• compression (articulation)

• tension

what are compression constraints of movement

• parts of contact between bones

• articular surfaces - surfaces of bone in contact with articulation

• tissues getting in between bones

what are tension constraints of motion

• ligaments

• blood vessels

• tendons

• muscles

these constrain motion but not usually considered part of the joint

what happens to the forces in a series chain

they are all the same

what happens to the forces in a parallel chain

all forces are added up

what is alignment for adjacent segments

inter-segmental/joint position in non-physiological DoF of motion - also known as joint position

angular position in coronal and axial planes, or its
translational position along any axis are all considered to be its “alignment”

what is alignment for non-adjacent segments

any DoF of position

e.g. – we can compare the axial alignment of the femur and talus – tibia and fibula between them,
but we’re interested in relative position of these non-adjacent segments above and below the leg

what are the constraints of squatting

• bi-articular muscles remain isometric

• muscles generate a net extension movement

  • only using uni-articular extensors

  • combo of one uni-articular and rest bi-articular

what are three bi articular muscles

• RF

• hams

• gastrox

what are three uni articular extensors

• soleus

• 3 vasti of quads

• Gmax

what determines compound of muscle force

• activation level

• anatomical cross sectional area (ACSA)

• normalized length

• normalized shortening velocity

what is active insufficiency

muscle is too short to the force decreases

what is passive insufficiency

muscle is too long and limits RoM

what is strength of muscle

the moment of a force it can produce

what are kin quantities

• mass

• energy (capacity to do work)

• work (energy transfer between bodies)

• force (agent of energy transfer between bodies)

• power (rate of work) P=force x velocity

what is the contact patch for stance (CP)

set of surfaces in contact with ground

what is base of support (BoS)

whole area within outline of CP

what is center of pressure (CoP)

point which application of total contact force equals distributed contact force

what is inertia

resistance to acceleration

what is the second law of acceleration equation

F=m x a

force equals mass times acceleration

why do extensors muscles work harder

they have greater muscle force in deep flexion

why are lengthening muscles stronger

because they have resistance from viscous forces

does lifting and lowering weight take the same amount of energy?

yes

why does it feel easier to lower/ decelerate lengthen muscles

• they are stronger

• have more decelerating capacity

• muscles are stronger when they act as decelerators

what are deformation mechanics

• contact forces causing acceleration or deformation

• elastic- go back to original shape

• plastic- remains deformed

what does standing squating and stance depends on

position

why do position joints change

change because of how mechanically hard it is

eg. when squatting, the moment arm of gravity increases, therefore mechanically harder to squat at the bottom of motion

coronal and axial plane of stance muscles and movements

• hip - abduction and external rotation with AbER muscles (10 of them)

• rear foot- supination (PF and adduction and IR) (with 4 muscles in this group)

how to determine strength of muscle

• force-length relationship and force-velocity relationship of muscles that change with the strength of the muscle

  • changes amount of force generated

  • how strong the muscle is determines how much flexion moment it can generate

what changes or determines strength of muscle

• components of the movement force

• force and movement arm

• moment arm being greatest at mid range of motion because there is no pully

how to change strength of muscle by changing position

• force-length relationship

• moment arm

motion of the rear food

• three linked DoF

• pronation and supination

• has two joints (talo-crural and sub-talar)

what is pronation

• foot having no arch

• flattens the arch and the talas rotates internally

what is the talo-crural joint and what does it do

• hinge joint

• dorsi-flexion and plantar-flexion

• axis of rotation

what is the sub0talar joint and what does it do

• mitred-hinge

• 1 physiologic DoF

  • pronation-supination in closed chain

  • inversion - eversion in open chain

what is equilibrium of stance

balance movements of gravity vs support

what are the movements of gravity - different at each LE joint

hip - flexion, adduction, internal rotaion

knee - flexion

ankle rear foot - talocrural dorsi flexion and sub-talar pronation

what are the support movements- opposite to moment of gravity at each joint

• hip - extension, abduction, external rotation

• knee - extension

• ankle rearfoot- talo-crucral planter flexion and sub-talar supination