Kinesiology Introduction: Chapter 1-4

Vocabulary terms covering basic kinesiology, biomechanics, planes of motion, types of forces, and simple machines as discussed in the lecture.

Anatomy

The actual structure of the body, including bones and muscles.

Physiology

The study of how body structures move and function.

Kinesiology

The study of human movement that looks at anatomy, physiology, physics, and mechanics.

Ulnar nerve

The specific nerve that controls the pinky finger.

Biomechanics

How movement is applied and how the body uses muscles to make certain movements.

Mechanics

The way force is exerted on an object.

Kinematics

The motion of a body work without regard to the forces and torques.

Kinetics

Describes the effect of forces and how those forces affect the body.

Arthrokinematics

Joint movement literally involving motions between joint surfaces such as rolling, gliding, or sliding.

Osteokinematics

Bone movement including actions like flexion, extension, abduction, and adduction.

Kinetic chain

A series of connected links or limb segments that influence the types of movements body parts make.

Closed kinetic chain

A movement where the distal segment is fixed and the proximal segment is free to move.

Open kinetic chain

A movement where the distal segment is free to move and the proximal segment is fixed.

Sagittal plane

Divides the body into left and right portions.

Frontal plane

Divides the body into anterior and posterior portions, resembling a pane of glass.

Horizontal plane

Also known as the transverse plane, it divides the body into upper (superior) and lower (inferior) portions.

Vertical axis

The axis on which internal and external rotation (turning) occurs.

Degrees of freedom

The number of planes within which a joint can move.

Uniaxial

Motion in one plane about one axis, representing $1$ degree of freedom.

Biaxial

Motion in two planes with two axes, representing $2$ degrees of freedom.

Triaxial

Motion in three planes about three axes, representing $3$ degrees of freedom, such as the hip joint.

Range of motion

The amount of motion that a joint can move in any possible direction.

Goniometer

An instrument used to measure the degrees of movement in a joint, consisting of a stabilizing arm and a moving arm.

Static

A non-moving state, such as standing still or working on sitting balance.

Dynamic

State of being in motion, where the body must compensate for differences in balance.

Scalar quantity

A measurement that has only magnitude, such as speed, length, area, volume, and mass.

Vector

A measurement that has both magnitude and direction, such as force, velocity, or acceleration.

Force

How much an object responds to being pushed (compression) or pulled (traction).

Gravity

An external force that acts as resistance and must be considered in posture and safety.

Weight

The amount of gravitational force placed on an object, acting directly downwards.

Ground reaction force

Upward force from a supporting surface that acts against downward resistance.

Friction

Force that creates heat, can cause inflammation or pain, and is increased by compression.

Linear forces

Forces that act along the same line, whether in the same or opposite direction.

Parallel forces

Forces occurring in the same plane, which can be in the same or opposite direction.

Force couple

A configuration of parallel forces acting in different directions to produce rotation, such as the movement of the scapula.

Concurrent forces

Two or more forces acting on an object at the same time from different directions.

Traction

When joint surfaces pull apart, which can facilitate pain management.

Compression

When two joints are pushed together, often caused by injury or used for weight-bearing facilitate proprioception.

Shear force

A force that occurs when objects slide across one another, such as downward and side-to-side pressure on spinal discs.

Concave

A surface that dips in, similar to a cave cut into a rock.

Convex

A surface that curves or goes out.

Torsion

Two opposing forces twisting an object.

Torque

The tendency of a force to produce a rotation about an axis; it depends on force and distance from the axis.

Moment arm

The perpendicular distance between the line of application of the force and the axis of motion.

Newton's first law of inertia

An object stays at rest or in motion at a constant state unless acted upon by an external force.

Newton's second law of acceleration

Acceleration is inversely related to the mass of the object and directly proportional to the amount of force applied.

Newton's third law

For every action, there is an equal and opposite reaction.

Equilibrium

When the sum of all forces acting on an object is equal to $0$.

Base of support

The area encompassed by the body's contact with a supporting surface.

Plumb bob

A tool used to create an imaginary vertical line to ensure straight center alignment.

Curvilinear motion

Movement that goes in different directions along a curved path rather than a straight line.

Angular motion

Motion around a fixed point where all parts move through the same angle but not the same distance.

Lever

A simple machine consisting of a rigid plank that can rotate about a fulcrum when force is applied.

First class lever

A lever where the axis is located between the force and the resistance.

Second class lever

A lever where the resistance is between the axis and the force.

Third class lever

A lever where the force is between the axis and the resistance.

Pulley

A grooved wheel used to change the direction of a force or the magnitude of force applied to lift a load.

Incline plane

A slanted surface, such as a ramp, used to move an object to a different level more safely.

Carpal bones

The $8$ bones of the wrist that fit together and permit slight gliding motion.

Saddle joint

A biaxial joint where each bone is concave in one direction and convex in the other, such as the carpometacarpal joint of the thumb.

End feel

The perceived sensation from moving a passive joint to the end of its range of motion, categorized as bony (hard) or soft.