Kinesiology >> Human Motion

Types of Motions

Classification based on path of motion

·  translatory motion (linear motion, translation)： a motion in which all parts of the moving body move toward the same direction

·  linear (or rectilinear) motion： a motion in which all parts of a moving body move in the same direction and the path follows a straight line
·  curvilinear motion： a motion in which the net motion of a moving body move toward the same direction although the path follows a curved line, e.g. the path of the center of mass of the body during level walking
		circular motion： a special form of curvilinear motion, which is the motion when a body moves along a circumference of a circle

·  rotary motion (angular motion, rotation)： a motion in which the object acts as a radius and all parts of the moving object rotate in the same angular direction and follow a circular path about a pivot point

·  angular motion： the rotary motion with one side of the moving object fixed, e.g. rotation of a limb

·  spin： the rotary motion with the axis of rotation around the center of mass

　

Classification based on repetition of motion

·  single motion： movement performed only once

·  repeated motion： same movement pattern that is done many times in a given time

·  reciprocal motion

·  oscillation： repeated motions in a small amplitude

·  pendulum motion： repeated motions like a pendulum

　

Classification based on degree of freedom

·  degree of freedom (DOF)： a minimum number of kinematic variables required to specified all positions and orientations of the segments in a body system i.e.

·  the number of planes in which the segments move

·  the number of the primary axes which the segments possess

·  Examples:

·  The joint that moves in one plane possesses one axis and has one degree of freedom

·  For the glenohumeral joint, there are three angular degrees of freedom and three linear degrees of freedom.

　

Classification based on relative segment kinematics

·  kinematic chain： a series of connected segment links

·  open kinematic chain motion： the joint motion with the distal segment moves free in space, e.g. raising lower leg or throwing a ball

·  closed kinematic chain motion： the joint motion with the distal segment is fixed, e.g. standing up or squatting down

·  In Neumann's book, "distal-on-proximal segment kinematics" and "proximal-on-distal segment kinematics" were used in stead of open and closed kinematic chain motion, respectively (Neumann 2002, p.7).

·  What kind of kinematic chain is performed as one-legged squatting?

　

Classification based on presence of muscle contraction

·  active motion： the motion that is caused by muscle contraction

·  passive motion： the motion that is created by sources other than muscle, such as from gravity

　

Classification based on joint kinematics

·  osteokinematic movement： movements between 2 bony segments

·  arhtrokinematic movement： movements between 2 articular surfaces