Human Movement Science

human movement system (HMS)

the collective components and structures that work together to move the body (muscular, skeletal, and nervous systems)

nervous system

Controls and coordinates movement by sending electrical signals to muscles

skeletal system

Provides structure, protection, and attachment sites for muscles; forms joints for movement

muscular system

Produces force and movement through muscle contraction

medial

Toward the midline of the body.

lateral

Away from the midline of the body.

ipsilateral

On the same side of the body.

contralateral

On opposite sides of the body.

superior

Above or toward the head.

inferior

Below or toward the feet.

anterior

Toward the front of the body.

posterior

Toward the back of the body.

saggital plane

Divides the body into left and right halves; flexion and extension occur here.
(Ex: squat, biceps curl)

frontal plane

Divides the body into front and back halves; abduction and adduction occur here.
(Ex: lateral raise)

transverse plane

Divides the body into top and bottom halves; rotational movements occur here.
(Ex: Russian twists)

flexion

Decreasing the angle between two body parts

extension

Increasing the angle between two body parts.

abduction

Movement away from the midline of the body.

adduction

Movement toward the midline of the body.

internal rotation

Rotation toward the midline of the body

external rotation

Rotation away from the midline of the body.

hyperextension

extension of a joint beyond normal limit/ROM

dorsiflexion

Bringing the top of the foot toward the shin.

plantarflexion

Pointing the toes downward.

osteokinematics

movement of a limb that is visible

arthrokinematics

description of a joint surface movement: roll, slide, and spin

radioulnar pronation

Palm rotates downward

radioulnar supination

Palm rotates upward

pronation of the foot

Foot rolls inward; arch flattens

supination of the foot

Foot rolls outward; weight shifts to outside edge

gait

motion of the lower extremities during walking, running

scapular retraction

Movement of the shoulder blades (scapulae) toward the spine

scapular protraction

Movement of the shoulder blades away from the spine

scapular elevation

Movement of the shoulder blades upward toward the ears.

scapular depression

Movement of the shoulder blades downward, away from the ears.

elasticity

the ability of soft tissues to return to resting length after being stretched

ligament

fibrous connective tissue that connects bone to bone

flexibility

the normal extensibility of soft tissues that allow for full range of motion of a joint

hypermobility

lack of neuromuscular support leads to a joint having more ROM than it should, risking injury

hypomobility

when ROM at a joint is limited

isotonic

force is produced as a muscle develops tension while visibly changing in length

eccentric muscle action

Muscle lengthens while producing force.
(Ex: lowering phase of a squat)

concentric muscle action

Muscle shortens while producing force.
(Ex: lifting phase of a curl)

isometric muscle action

Muscle produces force without changing length.
(Ex: plank hold)

agonists

The primary muscles responsible for producing a specific movement

antagonists

The muscle that opposes the action of the agonist on the opposite side of a joint

synergists

Assists the agonist in performing a movement

stabilizer

Supports and stabilizes a joint during movement.

kinetic chain

The interconnected system of joints and muscles working together to produce movement.

open kinetic-chain exercise

Distal segment (hand/foot) moves freely.
(Ex: leg extension)

closed kinetic-chain exercise

Distal segment is fixed against a surface.
(Ex: squat, push-up)

overactive muscle

A muscle that is tight or excessively active, often limiting proper movement

underactive muscle

A muscle that is weak or inhibited, often contributing to compensation patterns.

length-tension relationships

A muscle produces optimal force at its resting length

muscle balance

when all muscles surrounding a joint have optimal length-tension relationships, allowing the joint to rest in a neutral position

altered length-tension relationship

when a muscle’s resting length is too short or too long, reducing the amount of force produced

muscle imbalance

when muscles on each side of a joint have altered length-tension relationships

stretch-shortening cycle

loading of the muscle eccentrically to prepare it for a rapid concentric contraction

series elastic component

springlike noncontractile component of muscle and tendon that stores elastic energy

amortizaton phase

the transition from eccentric loading to concentric unloading during the stretch-shortening cycle

stretch reflex

neurological signal from the muscle spindle that causes a muscle to contract to prevent excessive lengthening

tendon

fibrous connective tissue that connects muscle to bone

force-couple relationship

the synergistic action of multiple muscles working together to produce movement around a joint

local muscular system

generally attatch on/near the vertebrae and serve the primary purpose of stabilizing the trunk of the body

joint support systems

muscular stabilization systems located in joints distal of the spine

global muscular system

comprised of larger muscles that initiate movements and function across 1 or more joints

deep longitudinal subsystem (DLS)

lower leg, hamstrings, and lower back region. create a contracting tension to absorb and control ground reaction forces during gait

posterior oblique system (POS)

latissimus dorsi, thoracolumbar fascia (connective tissue of the low back) and contralateral gluteus maximus provide a functional element of stability to the LPHC as a whole

anterior oblique system (AOS)

obliques, adductor muscles, hip external rotators - creates stability from the trunk, through the pelvis, to the hips - contributes to rotational movement

lateral subsystem (LS)

lateral hip (gluteus medius) and medial adductors, and contralateral quadratus, lumborum - provides movement in the frontal plane (side to side)

rotary motion

movement of the bones around the jointd

torque

a force that produces rotation

motor behavior

motor response to internal and external environmental stimulus

motor control

how the CNS integrates internal and external sensory information with previous experiences to produce a motor response

muscle synergies

groups of muscles that are recruited simultaneously by the CNS to provide movement

mechanoreceptors

specialized structures that respond to mechanical forces (touch and pressure) within tissues that then transmit signals through sensory nerves

proprioception

the body’s ability to naturally sense its general orientation and relative position of its parts

sensorimotor integration

cooperation of the nervous and muscular system in gathering and interpreting movement and executing movement

external feedback

info provided by some external source such as fitness professional, video, mirror, or heart rate monitor to supplement the internal environment

internal feedback

process whereby sensory info is used by the body to reactively monitor movement and the environment

neuromuscular efficiency

the ability of the NS to recruit the correct muscles to produce force, reduce force, and dynamically stabilize the body’s structure in all 3 planes of motion