Use the movement terms precisely.

Movement and exercise

Active range of motion

The movement a person produces using their own effort. The setup, symptoms, and task instructions affect the result.

Passive range of motion

Movement produced with external assistance. The amount of assistance and testing position matter when comparing it with active range.

Dorsiflexion

At the ankle, bringing the top of the foot and front of the shin closer together. See ankle mobility.

Flexion and extension

Terms describing joint movement, commonly bending and straightening. The exact convention depends on the joint.

Moment arm

The perpendicular distance from an axis of rotation to a force’s line of action. Along with force magnitude, it determines the turning effect in a simplified model. See movement mechanics.

External load

Resistance applied from outside the body, such as a weight, band, or object. The same load can create different demands in different positions.

Volume

The amount of work described by a chosen measure, such as sets and repetitions, duration, distance, or contacts. State which measure you use.

Intensity

A context-dependent description of how demanding an exercise is. It might mean external load relative to capacity, pace, or perceived effort. Name the definition.

Isometric exercise

Force production with little visible joint movement. Internal muscle-tendon behavior can still change. See tendon loading.

Concentric and eccentric muscle action

Respectively, muscle shortening and lengthening while producing force. A resistance exercise often includes both.

Repetitions in reserve (RIR)

An estimate of how many further repetitions could be completed to a defined standard. Estimates contain error; stopping because of symptoms complicates interpretation.[1]

Rating of perceived exertion (RPE)

A rating of perceived effort using a specified scale. Different scales have different anchors, so “RPE 7” needs a definition.

Progressive overload

Adjusting training demands over time to support adaptation. The appropriate variable and rate depend on the goal, capacity, recovery, and clinical context.

Pain, balance, and learning

Pain

A personal sensory and emotional experience associated with actual or potential tissue damage, or resembling that experience. Biological, psychological, and social factors influence it.[2]

Nociception

The nervous system’s encoding of potentially harmful events. It is related to pain but is not the same experience or measurement.[2]

Symptom irritability

A clinical description of how readily symptoms are provoked, their severity, and how long they take to settle. It is not simply the age of an injury.

Proprioception

Sensing body position and movement, with aspects of effort and force. It contributes to balance but is not synonymous with a balance test.[3]

Retention

Performance of a practiced skill after a delay. It helps examine what remains beyond the practice session.[4]

Transfer

Using a learned skill in a changed task or context. Improvement in one drill does not guarantee useful transfer.[4]

Contextual interference

The challenge created by switching among task variants during practice. Random and blocked schedules can produce different practice and later-learning results; greater difficulty is not always preferable.

Measurement and evidence

Reliability

The consistency of a measurement under specified conditions, including how well it distinguishes among people. Reliability is not a guarantee of accuracy or clinical importance.

Measurement error

Variation in a score that is not attributable to a real change in the attribute being measured.[5]

Minimal detectable change (MDC)

An estimated threshold beyond measurement error for a particular instrument, method, and confidence level.[5]

Minimal important change (MIC or MCID)

A change judged important using a particular outcome, population, method, and reference. It answers a different question from MDC.[5]

Limb symmetry index

A comparison between limbs, often expressed as a percentage. Record the original scores and reference side; symmetry can conceal low capacity on both sides.

Between-group difference

The difference between the outcomes of comparison groups. It addresses a different question from improvement within one group.

Confidence interval

An interval expressing uncertainty in an estimated effect under a statistical method. It does not describe the range of individual treatment responses.[6]

Standardized mean difference (SMD)

A difference expressed in standard-deviation units, often used to combine studies measuring the same outcome with different instruments. It is not a percentage improvement.[7]

Relative and absolute effect

A relative effect compares outcomes as a ratio; an absolute effect expresses the difference on the underlying risk or outcome scale. Baseline risk affects the absolute benefit associated with a relative risk reduction.[7]

Certainty of evidence

Confidence in an effect estimate for a particular outcome after considering limitations such as bias, inconsistency, indirectness, imprecision, and publication bias.[8]

Keep the definition beside the decision

Use the research guide to apply the measurement terms, and the loading guide to turn exercise terms into a useful record. If a paper uses a different definition, report that definition before comparing its result with another study.