Glossary of Terms

Get clued up with the relevant terms with our all-encompassing health and fitness glossary.


The region between the diaphragm and the pelvis.
Movement away from the midline of the body.
Absolute Strength:
The maximum force that an individual’s muscle can produce is a single voluntary effort, regardless of the rate of force production.
Active Range of Motion:
The degree of motion that occurs between two adjacent segments through voluntary contraction of the agonist.
A practice, chiefly in Chinese medicine, of attempting to cure illness or relieve pain by puncturing specific areas of the skin with needles.
Sharp, brief or severe; the initial stage of an injury
To adjust to new conditions.
Movement toward the midline of the body
The abnormal union of body tissues that are normally separate (similar to scar tissue).
Fatty substance
Aerobic exercise:
Exercise occurring in the presence of molecular oxygen in the muscle.
Afferent Neuron:
Sensory neuron carrying information toward the central nervous system.
Ability to start, stop, and move the body quickly in different directions.
A muscle responsible for producing a specific movement through concentric muscle action.
Amino Acids:
A class of organic compounds that are building blocks from which protein is constructed.
Anaerobic exercise:
Exercise occurring in the absence of molecular oxygen in the muscle.
Anatomical Position:
Standing erect, with feet and palms facing forward.
Anorexia Athletica:
The use of excessive exercise to lose weight, normally associated with anorexia nervosa.
Anorexia Nervosa:
An eating disorder characterized by a distorted body image in which a person does not take in a sufficient amount of calories, eventually causing harm to the body, and sometimes death.
A muscle responsible for opposing the concentric muscle action of the agonist.
Anterior Tilt:
Pelvic tilt in which the vertical plane through the anterior-superior spines is anterior to the vertical plane through the symphysis pubis.
Anatomical term referring to the front of the body; toward the front.
A structure attached to the body such as the upper and lower extremities.
Inflammation of a joint.
A joint or connection of bones.
Anterior Superior Iliac Spine.
Imbalance of the arrangement of parts. Not moving together.
Wasting away of any part, organ, tissue or cell.
Autogenic Inhibition:
Inhibition of the muscle spindle resulting from the Golgi tendon organ stimulation.
Without blood supply.
Forceful tearing away of any part of a structure.


A state of equilibrium; a state in which the body has the ability to move in space in a controlled movement.
Fast, dynamic movement.
Basal Metabolic Rate (BMR):
The rate at which the body expends energy while at rest.
With reference to two sides.
Biomechanical Efficiency:
How effectively the body operates with absolute minimal stress on specific joints.
The study of motion and the effects of forces relative to the body.
Blood Pressure:
Has two measurable components:

  • Systolic – Used to estimate the pressure exerted against the arterial walls as blood is forcefully ejected during the ventricular contraction (systole).
  • Diastolic – Used to estimate the pressure exerted against the arterial walls when no blood is being forcefully ejected through the vessels (diastole).
  • (REFERENCE – “Essentials of Strength Training and Conditioning” by Baechle & Earle)
Body Composition:
Refers to the ratio of an individual’s percentage of fatty mass to fat free tissue mass (I.E. muscle, organs, etc.).
Body Part Exercises:
Exercises that isolate a particular muscle group.
A synovial-lined sac existing between tendons and bone, muscle and muscles and any other site in which movement of structure occurs.


Calcium Deposit:
Abnormal hardening of soft tissue, usually from repeated injury.
The amount of heat required to raise 1 kg of water 1°C; unit of energy.
Relating to the heart and blood vessels.
Center of Gravity:
The center of a body’s mass. In the human body it is the point, which all parts are in balance with one another. It is dependant on current position in space, anatomical structure, gender, habitual standing posture and if external weights are being held.
Circuit Training:
Selected exercises or activities performed in sequence.
Closed Chain Exercise:
Exercise that occurs when the distal segment of an extremity is fixed, such as performing a squat, in which the foot is in contact with the ground.
Closed Skill:
One for which the environment is stable and predictable.
The protein of connective tissue fibers.
Combined Movement:
Any combination of exercises or trunk movements.
Concentric Action (shortening):
The force produced by the muscle is greater than the external resistance; therefore the muscle is able to shorten while overcoming the external load.
Connective Tissue:
The body’s supporting framework of tissue consisting of strands of collagen, elastic fibers between muscles and around muscle groups and blood vessels, and simple cells.
A shortening of muscle fibers, which occurs when tension is generated across numerous actin and myosin filaments.
Harmonious interaction; synchronizing movement.
Core Training:
Refers to the progressive training of the musculature of the lumbo-pelvic-hip complex.
A spasmodic contraction of one or many muscles.
Referring to the skin.


Davis’s Law states:
that soft tissue models along the line of stress. Which when applied means we must train in optimal alignment and never allow gross compensations or the tissues will adapt to the potential detrimental forces placed upon the human movement system (kinetic chain).
Diastolic Blood Pressure:
Pressure exerted by the blood on the vessel walls when the heart is in its filling stage (bottom number).
Further away from the center or median line.
A class of drugs used to force the kidney to excrete more sodium than usual. Increased sodium excretion causes increased water excretion, so urine volume increases. The increased sodium excretion is desirable and therapeutic in disorders causing abnormal fluid retention due to heart failure, liver failure or kidney failure.
Pertaining to the back.
Dynamic Exercise:
Joint movement resulting from muscular exertion (concentric or eccentric).
Dynamic Posture:
The maintenance of the instantaneous axis or rotation of any/all working joints.


Eccentric (lengthening) Action:
The force produced by the muscle is less than the external resistance, but it is causing the joint movement to occur more slowly than the external resistance would tend to make the limb move.
Accumulation of abnormal quantities of fluid in spaces between the cells of the body. Edema can accumulate in almost any location in the body.
Efferent Neuron:
Conducts impulses from the CNS to the effector organ (E.G., motor neuron).
The power to produce and effect.
A charged ion capable of conducting electrical current when in solutions.
Electromyography (EMG):
The recording of the electrical activity in the muscle; recording the action potentials in a muscle or in muscle groups.
The thin connective tissue surrounding each muscle cell.
The potential or capacity to do work.
The sheath of fibrous connective tissue surrounding a muscle.
Dorsal exercises or trunk movements performed in the sagittal plane around a transverse axis.
External Rotation:
Rotation occurring away from midline; outward rotation.


A general term for a layer or layers of loose or dense fibrous connective tissue.
In terms of training and exercise it may be defined as: The failure of one or more neuromuscular energy systems (phosphagen, glycolysis, & oxidative systems), cause by repetitive movements (exercising), of given intensities (intrinsic/extrinsic resistance loads, etc.), over specific durations (minutes, hours, days, weeks, etc).
Feldenkrais Method:
A method of working with the body devised by Mosh Feldenkrais. Its main goal is to deprogram poor postural and muscular habits and reprogram new patterns by gentle awareness through movement exercises.
The formation of fibrous tissue. Fibrosis is caused by many factors including injury, inflammation and infection.
Fixed Pattern:
Many machines are designed with a predicable pattern of movement. Equipment manufacturers have designed machines to aid in the fixation of a joint(s), allowing for precise placement of limbs. This ensures that a target area is maximally recruited while other muscles remain largely dormant.
The ability to readily adapt to changes in position or alignment; may be expressed as normal limited, or excessive.
Anterior exercises or trunk movements performed in the sagittal plane around a transverse axis.
Force Couple:
Two forces that are equal in magnitude and, acting in opposite directions, produce rotation about an axis.
An interaction between two objects in the form of a push or pull that may or may not produce motion.
Free Weights:
Free weights are often used without the constraint that machines offer. For example, in the standing position, the entire body supports the free weight, taxing a larger portion of the body’s musculature than would a traditional machine. The movement of a free weight is constrained by the lifter rather than a machine, requiring muscles to work in stabilization as well as in motion. The lifting of free weights involves a more natural coordination of several muscle groups.
Rate of reoccurrence.
(n) The acts or operations expected of a person or thing. The ability of a living being to perform in a given way or capacity for a particular kind of performance. (v) To perform the duties or function of. To serve, operate, perform.
Functional Carry-over:
The skill obtained through training that can be carried over to every day function.


Generalized Motor Programs:
Consists of a stored pattern, which can be modulated slightly when the program is executed. This allows the movement to be adjusted to meet the altered environmental demands.
Genu Valgum:
Knock-knees, defined as a medial displacement of the distal end of the distal bone in the joint.
The presence of glucose in the blood.
Golgi Tendon Organ:
A sensory organ. Located within the tendon, that has a high threshold and responds to (great amounts of tension on the tendon), regardless if produced by stretch or contraction. When stimulated, will cause an inhibition of the agonist and facilitation of the antagonist.


Heavy Weight Training:
usually defined (changes based on author) as a load used to enhance strength adaptation or neural adaptation. The repetition for strength are usually set @ 6-8 using 3-4 sets @ 75-85% intensity. Neural adaptations utilize 1-5 repetitions for 4-8 sets @ 85-100% intensity.
Maintenance of the body’s internal environment.
A prefix meaning above, beyond or excessive. For example, hypertonic means tone beyond normal.
Excessive curvature of the thoracic (middle) spine.
Excessive curvature of the lumbar (lower) spine and/or cervical spine.
Excessive growth of an organ and/or tissues.
A prefix meaning below or deficient. For example, hypotonic means tone below normal.
Lack of physical activity.


The state or condition of lacking balance. (Muscular imbalances) Lack of balance and normal symmetry within the muscular system.
An encroachment on the space occupied by soft tissue, such as nerve or muscle. In this text, impingement refers to nerve irritation (i.e., from pressure or friction) associated with muscles.
In Vitro:
Functioning outside of, or detached from the body.
In Vivo:
Functioning within the body.
Nerve stimulation of a muscle.
Internal Rotation:
Rotation occurring toward midline; movement inward.
Intersegmental Stabilization:
Scientists have categorized the trunk muscles into inner and outer structure groups based in their main function in stabilization. The inner structure includes deep muscles with attachments to the lumbar vertebrae. Anatomically, being closer to the center of rotation of the spinal segments, and having shorter muscle lengths allow for intersegmental control. The outer structure includes the larger, more superficial muscles that span many vertebral segments. Besides moving the spine, their innermost function is to balance the external loads applied to the trunk. This requires the deep muscles to handle the left over forces transferred to the lumbar region. Research has shown that superficial muscle contribution to spinal stiffness is not enough to provide intersegmental stability. A small increase of activity in the deep muscles has been shown to prevent instability.
The space within an organ.
The same side of the body.
Isokinetic Exercise:
Contractions performed at constant angular velocity.
When a weak link is identified, it may be important to emphasize the target area by isolating the joint movement. Isolated strength can then be integrated with the rest of the body.
Normally defined as a single joint motion. It is important to remember that one cannot isolate a muscle while resistance training. For example, immediately following a load application, the stabilizer muscles become partially involved, due to the machine’s assistance. The outside assistance (machine) helps the body or specific joint(s) to remain stable while the prime movers cope with the load. Although we cannot isolate muscles, we can use certain machines to isolate a joint(s), which will emphasize a target area.
Isometric Action (iso = same; metric = length):
The force produced by the muscle is equal and opposite to the external resistance, therefore, there is no net change in muscle length – no limb movement.(Also referred to as Static exercise)
Isotonic exercise:
Exercise involving constant muscle contraction.


Joint Capsule:
The thin, cartilaginous, fatty, fibrous, membranous structure that envelopes a joint. Fluid inside the joint capsule lubricates the area, allowing bones to glide smoothly against each other.


Kegal Exercises:
Exercises designed to gain control of and tone the pelvic floor muscles by controlled isometric contractions and relaxation of the muscles surrounding the vagina.
Area of study that examines the spatial and temporal components of motion (position, velocity, acceleration).
The scientific study of human movement.
Kinetic System:
Any system where each part of it is in some way influenced when changes occur in other parts of the system.
A condition characterized by an abnormally increased convexity in the curvature of the thoracic spine as viewed from the side.


Length-Tension Ratios:
The relationship between the length of the muscle and the tension produced by the muscle.
A fibrous connective tissue that connects bone to bone or cartilage to bone, supporting and strengthening a joint.
An abnormal anterior curve, usually found in the lumbar region, and as such is an exaggeration of the normal anterior curve (avoid use of the term “normal lordosis”); often called “hollow back.” It is accompanied by anterior pelvic tilt and hip joint flexion. If used without any modifying word, it refers to lumbar lordosis. In the thoracic region, occasionally, there is a slight lordosis which is a reversal of the normal posterior curve. In a typical forward head position, the neck is in a position of extension that is greater than the normal anterior curve and as such resembles a lordosis. (REFERENCE – “Muscles Testing and Function” By Kendall, McCreary, & Provance)
Bones in a joint that are no longer in the correct functional position to each other. Means the same as dislocation.
Lymph Node:
A small oval structure located along lymphatic vessels.
Often pertains to the system of vessels involved with drainage of bodily fluids.


Machine Assistance:
Outside support which equates to less overall muscular effort.
Maintenance of Center of Gravity:
Most activities involve the influence of gravity in a three-dimensional, unstable environment.
stands for Metabolic Equivalent – 1 MET is equal to the amount of energy expended during 1 minute at rest, which is roughly 3.5 milliliters of oxygen per kilogram of bodyweight per minute (3.5 ml/kg/min) or 1.2 kcals per minute for a 70 kg (150 lb.) person.
Very slow changes in progression.
The vitamins and minerals that help structure the body, as well as regulate all reactions and processes that take place within the body.
Capable of moving or being moved readily. (Joint mobility) Movement around an entire joint.
Motor Neuron:
Neurons that carry impulses from the brain and spinal cord to the muscle receptors.
Motor Unit:
A motoneuron and all the muscle fibers it stimulates, innervates, or activates. The size of the motor unit is usually related to the degree of control required by the whole muscle.
A result of the harmonious functioning of the sensory and motor systems in concert with the central and peripheral nervous system.
Musculoskeletal System:
The skeleton and its associated bones, the ligaments, tendons and the muscles.
Myofascial Unit:
A muscle and the fascia, which directly surrounds it.
Skeletal muscles ensheathed by fibrous connective tissue.


Nervous System:
The brain, spinal cord and all the nerves in the body.
Neural Drive:
A measure of the number and amplitude of nervous system impulses to a muscle.
A conducting cell in the nervous system that specialized in generating and transmitting nerve impulses.
Neutral Posture:
A halfway zone between a person’s ability to flex and extend. Neutral posture involves a minimal amount of stress and strain, and is conducive to maximal efficiency of the body. (Also called Ideal posture)
Neutralizer Muscle:
A muscle responsible for eliminating or canceling out an undesired movement.


One Repetition Max:
The greatest amount of weight a person can lift one time in good form.
Open Chain Exercise:
Exercise that occurs when the distal segment of an extremity is free, such as performing a knee extension exercise
Open Skill:
One for which the environment is stable and unpredictable.
A decrease in bone density.
Stressing the body or parts of the body to levels above what is normally experienced.


Path Variable:
Many path options.
Pattern Overload:
Many repetitions performed in the same pattern can lead to overloading soft tissues beyond necessary stimulus.
Pelvic Girdle:
The two hip bones.
Composed of the two hip bones, sacrum and coccyx.
Perceived Volitional Fatigue:
Similar to Rate of Perceived Exertion (RPE). The exerciser is choosing/deciding on a specific level of exertion/fatigue based on how they feel.
The fibrous connective tissue, which surrounds the surface of bones.
The connective tissue enveloping bundles of muscle fibers.
The three basic planes of reference are derived from the dimensions in space and are at right angles to each other.

Types of planes:

  • Sagittal:Is vertical and extends front to back. It may also be called anterior-posterior plane.
  • Coronal Is vertical and extends from side to side. It is also called the frontal or lateral plane, and divides the body into anterior and posterior sections.
  • Transverse:>Is horizontal and divides the body into upper and lower portions. It is also termed the horizontal plane.
Popliteal Space:
The space behind the knee joint. The space is bounded by ligaments and contains soft tissue including nerves, fat, membranes and blood vessels.
Postural Response:
A change of body position that leads to a change in the projection of the center of mass.
Ability to exert muscular strength quickly.
Refers to the prevention of injury by training the joints and muscles that are most susceptible to injury in an activity. Unlike rehabilitation, prehabilitation deals with injuries before they occur.
Prediction of the course of an injury or disease, including its end result.
Lying face downward.
The neurological sense that allows one to know not only where one is in space, but also the position and location of each individual part and joint.
Proprioceptive Neuromuscular Facilitation (PNF):
A method of promoting a response of neuromuscular mechanisms through the stimulation of proprioceptors in an attempt to facilitate increased range of motion, increased strength and movement pattern control.
Nearer to the center or median line, or to the thorax.
Done in two ways: 1. Beginning with sets that use a lighter load and higher rep count, progressing to heavier load and lower rep count. 2. Beginning with sets that use a heavier load and lower rep count, progressing to lighter load and higher rep count.


The angle formed by the longitudinal axis of the femur and the line of pull of the patellar ligament.


Range of Motion:
The range, measured in degrees of a circle, through which a joint can be flexed and extended. 1. Active range of motion: Voluntarily moving a joint through a controlled range of motion; active movement of a joint. 2. Passive range of motion: Having an external force move a joint through its range of motion.
Reciprocal Inhibition:
The concept of muscle inhibition caused by a tight agonist, which inhibits its functional antagonist.
The act of repeating an action/ movement.
Resting Heart Rate:
A measure of heat beats per minute when the body is completely at rest, such as in the morning right out of bed.
Exercises or trunk movements performed in the transverse plane, around a longitudinal axis, to the left or right.


The Saggital plane (otherwise known as the anterior/posterior plane), is an imaginary line that divides the body into right and left halves. Sagittal plane exercises lie on the frontal axis.
Is a shoulder movement that is in-between a shoulder lateral raise and a front raise. You raise your arm at a 45-degree angle from your body, so it’s not straight in front (front raise) of you or straight out to the side (lateral raise) AND the thumb is pointing upward. This allows the greater tubercle of the humerus to avoid impingement with the acromion process.
Scapulohumeral Rhythm:
The movement relationship between the humerus and the scapula during arm raising movements.
Soft Tissue:
Usually referring to myofascial tissues, or any tissues that do not contain minerals (such as bone).
Ability to move the whole body quickly.
Remaining consistent and steady. Joint stability: Integrity of the entire joint.
The ability to control the body both statically and dynamically.
Stabilizer Muscle:
A muscle responsible for stabilizing an adjacent segment.
Static Posture:
The position of the body at rest, sitting, standing or lying.
Sticking Point:
The point in a movement or exercise through which movement is most difficult. This is especially pertinent in free motion exercises like the squat where posture and body position are so demanding – it is often very tempting to break form in order to pass through the sticking point, and that is where the body becomes most susceptible to precarious positions and potential injury.
Another example:
The point in the range of motion where the person performing is at a biomechanical DIS-advantage.
The 90-degree position in an isolated arm curl.
A physiological or psychological response to a stressor beyond what is needed to accomplish a task.
Any stimulus or condition that causes physiological arousal beyond what is necessary to accomplish the activity.
Structural Exercises:
Exercises that require neural communication between muscles, and promote coordinated use of multi-joint movements.
Below the skin.
Super Setting:
Done in two ways: 1. Two exercises involving ANTAGONISTIC muscles performed back-to-back.(ex: overhead press/pull-ups) 2. Two exercises involving the SAME muscle group performed back-to-back. (ex: overhead press/lateral raise).
Lying with the face upward.
Synchronization of Motor Units:
A neural factor that could increase force production. The greater the synchronization, the greater the number of motor units firing at any one time.
A set of symptoms occurring together, the sum of signs of a morbid (sad, melancholic) state.
A thin layer of connective tissue with a free smooth surface that lines the capsule of a joint. Synovial fluid lubricates and facilitates movements of the joint.


Pertaining to touch.
The rate of speed of a repetition.
A cord of dense, tough tissue connecting a muscle with a bone or part.
Primary male hormone responsible for skeletal muscle development.
TFL (Tensor Fasciae Latae):
A muscle of the hip and leg. Origin – Iliac crest just posterior to the ASIS. Insertion – Tibia by way of the Iliotibial tract (IT band). Function(s) – Concentric – Hip flexion, hip Abduction, hip internal rotation. Isometric – Dynamic stabilization of the lumbo-pelvic-hip complex. Eccentric – Deceleration of hip extension, hip Adduction, and external rotation.
The chest or rib region of the trunk consisting of twelve vertebrae.
The region between the neck and abdomen.
Shortness; denotes a slight to moderate decrease in muscle length; movement in the direction of lengthening the muscle is limited.
Transverse Abdominus:
Muscle inserting on the last six ribs, iliac crest, inguinal ligament, lumbodorsal fascia, linea alba and pubic crest; increases intra-abdominal pressure.
The part of the body to which the upper and lower extremities attach.


Pertaining to one side.


Individual bones that comprise the spinal column.
VO2 Max:
Maximal oxygen consumption.
Refers to total work load done within the context of a training session and/or particular time frame (i.e.Total sets, reps, load, etc.)
Voluntary Movement:
A movement performed under the volition of an individual.


A non-medical term meaning an injury to the neck caused by hyperextension and/or hyperflexion.
The product of force and distance.


Freedom of the self from its temporary state through methods such as exercise and relaxation.
A person who practices yoga.