angular kinematics

sagittal plane

divides body into left and right

frontal plane

divides body into front and back

transverse plane

divides the body into superior and inferior parts

medial-lateral axis

horizontally oriented; passes through body from side to side; perpendicular to sagittal plane

Sagittal plane movements

rotates around the medial-lateral axis

Ex.: flexion, extension, hyperextension, dorsiflexion, plantar flexion

anterior-posterior axis

perpendicular to frontal plane

longitudinal axis

perpendicular to transverse plane

Frontal plane movements

rotates around the anterior-posterior axis

Ex.: Abduction, adduction, lateral flexion, wrist radial/ulnar deviation, ankle inversion/eversion, knee and elbow valgus/varus

Transverse plane movements

rotates around the longitudinal axis

Ex.: Internal/external rotation, right/left rotation,forearm supination/pronation, shoulder horizontal abduction/adduction

angular distance

how far the point rotated around the axis (scalar)

angular displacement

how far the point rotated around the axis in a specific direction (vector) (+ or -)

angular speed

how fast the point is rotating around the axis

angular velocity (w)

how fast the point is rotating around the axis in a specific direction

sign of velocity indicates

direction (clockwise or counterclockwise)

clockwise (sign of velocity)

- (negative)

counterclockwise (sign of velocity)

+ (positive)

tangential velocity (V)

Velocity that is parallel (tangent) to a curved path.

V=wr

radius of rotation (r)

the distance between the axis of rotation and the point of interest on a system

greater the tangential velocity

greater the angular velocity and longer the radius of rotation

advantages of a longer limb when throwing

longer radius of rotation → greater velocity → farther distance

the greater the angular displacement

the greater the tangential displacement

tangential displacement (vector)

how far the point rotated around the axis in a specific direction (+ or -)

tangential acceleration

linear acceleration in the tangential direction (rate of change in magnitude of velocity)

tangential acceleration increases

increasing angular acceleration or radius of rotation

radial acceleration

rate of change in direction of velocity

radial acceleration direction

towards the center of rotation

factors effecting radial acceleration

swinging the object and turning the corner

factors of swinging the object and increasing radial acceleration

angular velocity and radius of rotation increase

factors of turning the corner and increasing radial acceleration

angular velocity increases and the radius of rotation (turning radius) decreases

centripetal force

a force that acts on the center around which the object is moving.

radial acceleration and centripetal force relationship

greater radial acceleration, the greater the centripetal force needed for object to stay in circular path

centripetal force increases as

radial acceleration and mass of object increases

Wide-Grip Bench Press Elbow

Name of Motion: Flexion/Extension

Plane/Axis: Sagittal/Medial-Lateral Axis

Primary Active Muscle: Triceps Brachii

Wide-Grip Bench Press Shoulder

Name of Motion: Horizontal/Abd/Adduction

Plane/Axis: Transverse Plane/Longitudinal Axis

Primary Active Muscle: Pectoralis Major

Closed-Grip Press Elbow

Name of Motion: Flexion/Extension

Plane/Axis: Sagittal/Medial-Lateral Axis

Primary Active Muscle: Triceps Brachii

Closed-Grip Press Shoulder

Name of Motion: Flexion/Extension

Plane/Axis: Sagittal/Medial-Lateral Axis

Primary Active Muscle: Pectoralis Major

A patient moves their elbow through +60 degrees of extension over 4 seconds. What was the average angular velocity of the elbow during this time?

60/4

How fast the golf club was rotating at the time of ball impact:

Golf: Instantaneous

How fast the figure skater was spinning during the jump:

Figure Skating: Average

The fastest angular velocity the pitcher’s arm reached during the pitching motion:

Pitching: Instantaneous