Protein
A macronutrient your body uses to repair tissue, support muscle growth, and make training adaptations possible.
- dietary protein
- protein intake
Glossary
Fitness Glossary
Quick definitions for the words fitness content throws around, with a trail into the articles, claims, and topic hubs that explain them more deeply.
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188 of 188 published terms shown
Anabolic window
The idea that there is a narrow post-workout period when protein must be eaten to maximize muscle gain.
- 30-minute protein window
- post-workout window
Meal timing
How you distribute meals or nutrients across the day, including around training.
- nutrient timing
Fat loss
A reduction in stored body fat, mostly driven over time by energy balance, habits, and training consistency.
- body fat reduction
- cutting
Spot reduction
The claim that training one body area can directly burn fat from that same area first.
- targeted fat loss
- belly fat targeting
Fasted cardio
Cardio done before eating, often promoted as a shortcut for burning more body fat.
- cardio before breakfast
- fasted training
Creatine
A well-studied supplement that helps recycle high-energy phosphate during short, hard efforts.
- creatine monohydrate
Fat burner
A supplement category marketed as increasing fat loss, often with claims stronger than the evidence supports.
- thermogenic
- weight-loss supplement
Hypertrophy
An increase in muscle size, usually from repeated resistance training plus enough food, protein, and recovery.
- muscle growth
Strength training
Training that uses resistance to build strength, muscle, coordination, and tolerance for harder work.
- resistance training
- lifting weights
Training to failure
Performing a set until you cannot complete another good rep with the target technique.
- muscle failure
- failure training
Recovery
The process of adapting between training sessions, supported by sleep, nutrition, stress management, and sensible programming.
- training recovery
Strength
The ability to produce high force against resistance.
Open termPower
The ability to produce force quickly.
Open termMuscular Endurance
Ability of a muscle or muscle group to repeat force over time.
Open termAerobic Fitness
The ability to sustain exercise using oxygen-dependent energy systems.
Open termAnaerobic Capacity
The ability to produce energy for hard effort when oxygen demand exceeds supply.
Open termMobility
Capacity to move a joint through usable range with control.
Open termStability
The ability to resist unwanted movement and control position.
Open termBalance
The ability to maintain control of the body's center of mass over the base of support.
Open termWork Capacity
The ability to tolerate and complete a given amount of training work.
Open termTissue Tolerance
How much stress a tissue can handle before symptoms or failure appear.
Open termAdaptation
Long-term change in performance or structure in response to training.
Open termLoad
The external resistance applied in an exercise.
Open termIntensity
How hard a training stimulus is relative to capacity.
Open termVolume
Total amount of training performed, often sets x reps x load.
Open termFrequency
How often a muscle, movement, or training session is performed.
Open termDensity
Amount of work completed per unit of time.
Open termSpecificity
Adaptation is specific to the demands you train.
Open termProgressive Overload
Gradually increasing training stress over time.
Open termVariation
Planned changes in exercise, load, rep range, or tempo.
Open termFatigue
Temporary reduction in performance or capacity after stress.
Open termReadiness
How prepared you are to train on a given day.
Open termStimulus
The training input that triggers adaptation.
Open termTraining Age
How long someone has been training seriously.
Open termExercise Order
The sequence exercises are performed in a session.
Open termRest Interval
The time taken between sets or efforts.
Open termPeriodization
Structured long-term organization of training.
Open termMacrocycle
The longest training block in a plan, often months to a year.
Open termMesocycle
A medium-length block within a larger plan.
Open termMicrocycle
The shortest planning block, usually about a week.
Open termBlock Periodization
Periodization organized into focused blocks of specific qualities.
Open termLinear Periodization
Plan that gradually shifts from higher volume to higher intensity.
Open termUndulating Periodization
Training variables change more frequently across the week or block.
- nonlinear periodization
Reverse Periodization
A model that starts with higher intensity and later emphasizes volume.
Open termTaper
Planned reduction in training load before a peak event.
Open termDeload
Temporary reduction in training stress to dissipate fatigue.
Open termPeaking
Training to maximize performance at a specific time.
Open termAccumulation Phase
Block that emphasizes building volume and base qualities.
Open termTransmutation Phase
Block that shifts toward more specific training qualities.
Open termRealization Phase
Block that converts fitness into performance readiness.
Open termConcurrent Training
Training strength and endurance qualities in the same program.
Open termSet
A group of repetitions performed without rest.
Open termRep
One complete repetition of a movement.
- a repetition
Working Set
A set that is meant to drive the main training stimulus.
Open termWarm-up Set
A lighter set used to prepare for working sets.
Open termTop Set
The heaviest or hardest set in a sequence.
Open termBack-off Set
A lighter set done after a top set.
Open termStraight Sets
Repeated sets using the same exercise, load, and rep target.
Open termPyramid Set
Sets that progress up or down in load across a sequence.
Open termDrop Set
A set continued after lowering the load.
Open termSuperset
Two exercises done back-to-back with little or no rest.
Open termGiant Set
Three or more exercises chained with minimal rest.
Open termCluster Set
A set broken into short intra-set rests.
Open termRest-pause
Brief pauses inserted inside a set to continue reps.
Open termMyo-reps
A high-rep activation set followed by short mini-sets.
Open termCircuit Training
A series of exercises performed with minimal rest between stations.
Open termEMOM
Every-minute-on-the-minute training format.
Open termAMRAP
As many reps or rounds as possible within a time limit.
Open termTabata
Short interval format using 20 seconds work and 10 seconds rest for eight rounds.
Open term1RM
The maximum load you can lift once with proper form.
Open termRM
A load that can be lifted for a specified number of reps.
Open termSubmaximal
Below maximal effort or load.
Open termRPE
Rating of perceived exertion, a subjective measure of effort.
Open termRIR
Repetitions in reserve; reps left before failure.
Open termTechnical Failure
Point where form breaks down enough that the set should stop.
Open termVolitional Failure
The point where the lifter chooses or is unable to continue.
Open termAutoregulation
Adjusting training based on readiness or performance feedback.
Open termVelocity-based Training
Using bar speed to guide load selection and fatigue management.
Open termBar Speed
How fast the bar or implement is moving during a rep.
Open termPower Output
Work done per unit time, often measured in watts.
Open termConcentric
The muscle shortens while producing force.
Open termEccentric
The muscle lengthens while producing force.
Open termIsometric
The muscle produces force without visible joint movement.
Open termIsotonic
A dynamic contraction in which the muscle changes length under load.
Open termIsokinetic
A contraction performed at a constant movement speed.
Open termStretch-shortening Cycle
A rapid eccentric-to-concentric transition that stores and reuses elastic energy.
Open termPlyometric
Explosive work that uses the stretch-shortening cycle.
Open termROM
Range of motion through which a joint moves.
Open termTempo
The speed and timing of each rep phase.
Open termTime Under Tension
How long a muscle is loaded during a set.
Open termSticking Point
The hardest part of a lift where force output dips.
Open termTorque
Rotational force around a joint or axis.
Open termForce
A push or pull that can change motion.
Open termImpulse
Force applied over time.
Open termRate Of Force Development
How quickly force rises.
Open termForce-velocity Relationship
The tradeoff between how hard and how fast a muscle can contract.
Open termCompound Lift
An exercise using multiple joints and muscle groups.
Open termIsolation Lift
An exercise that emphasizes one joint or muscle group.
Open termMulti-joint
Involving movement at more than one joint.
Open termSingle-joint
Involving movement at primarily one joint.
Open termOpen-chain
The limb's distal end is free to move.
Open termClosed-chain
The limb's distal end is fixed against a surface.
Open termUnilateral
Training one limb or side at a time.
Open termBilateral
Training both limbs together.
Open termSagittal Plane
Plane dividing the body into left and right halves.
Open termFrontal Plane
Plane dividing the body into front and back halves.
Open termTransverse Plane
Plane dividing the body into upper and lower parts.
Open termHip Hinge
Movement pattern dominated by hip flexion and extension.
Open termSquat Pattern
Movement pattern dominated by knee and hip flexion/extension.
Open termLunge Pattern
Split-stance lower-body pattern with unilateral loading.
Open termPush Pattern
Any pressing action away from the body.
Open termPull Pattern
Any rowing or pulling action toward the body.
Open termCarry
Moving a load while maintaining posture and bracing.
Open termBracing
Creating torso stiffness to transfer force and protect the spine.
Open termStabilization
Controlling unwanted movement while producing force.
Open termHIIT
High-intensity interval training with hard efforts and recovery periods.
Open termSIT
Sprint interval training using very short all-out or near-all-out bouts.
Open termLISS
Low-intensity steady-state cardio.
Open termMICT
Moderate-intensity continuous training.
Open termSteady-state Cardio
Continuous aerobic work performed at a relatively constant intensity.
Open termZone 2
Informal label for lower aerobic intensity near easy endurance work.
Open termThreshold Training
Training near the highest intensity that can be sustained for a long time.
Open termInterval Training
Alternating harder work bouts with recovery periods.
Open termFartlek
Unstructured speed-play training with variable pace changes.
Open termTempo Run
Sustained run at a comfortably hard pace.
Open termLong Slow Distance
Long-duration low-intensity endurance work.
Open termVO2max
Maximal rate of oxygen uptake during intense exercise.
Open termLactate Threshold
Intensity at which lactate begins to rise faster than it can be cleared.
Open termVentilatory Threshold
Exercise intensity where ventilation increases disproportionately to workload.
Open termDOMS
Delayed onset muscle soreness after unfamiliar or strenuous exercise.
Open termEPOC
Excess post-exercise oxygen consumption after exercise ends.
Open termGlycogen Depletion
Reduction in stored carbohydrate in muscle or liver.
Open termGlycogen Supercompensation
Rebound increase in glycogen storage after depletion plus recovery.
Open termCentral Fatigue
Fatigue originating in the nervous system's drive to muscle.
Open termPeripheral Fatigue
Fatigue arising within the muscle itself.
Open termNeuromuscular Fatigue
Decline in force or power due to nervous and muscular factors.
Open termHormonal Response
Changes in hormones after exercise, such as acute stress responses.
Open termHeart Rate Variability
Beat-to-beat variation in heart rate, often used as a recovery proxy.
Open termSleep Debt
Accumulated shortage of sleep relative to need.
Open termActive Recovery
Low-intensity movement used to aid recovery.
Open termPassive Recovery
Rest with no planned movement.
Open termBMR
Basal metabolic rate, the energy cost of basic life functions at rest.
Open termRMR
Resting metabolic rate, the energy you burn at rest.
Open termEnergy Availability
Energy remaining for body functions after exercise expenditure.
Open termCalorie Surplus
Eating more energy than you expend.
Open termCalorie Deficit
Eating less energy than you expend.
Open termMaintenance Calories
Intake that roughly matches energy expenditure.
Open termBulk
Intentional phase of eating more and training to gain mass.
Open termCut
Intentional fat-loss phase, usually with a calorie deficit.
Open termRecomp
Body recomposition: gaining muscle and losing fat at the same time.
Open termLean Mass
Body mass excluding fat mass.
Open termFat Mass
The total mass of body fat.
Open termBody Recomposition
Improving body composition without large scale weight change.
Open termHypertrophy Training
Training that emphasizes muscle growth.
Open termPower Training
Training that emphasizes rapid force production.
Open termBodybuilding
Physique-focused training aimed at muscle size and shape.
Open termPowerlifting
Strength sport built around squat, bench press, and deadlift.
Open termOlympic Weightlifting
Sport centered on the snatch and clean & jerk.
Open termCalisthenics
Bodyweight-based strength training.
Open termFunctional Training
Training intended to transfer to daily life or sport tasks.
Open termGPP
General physical preparedness, or broad base fitness.
Open termS&C
Strength and conditioning, the field covering performance training.
Open termMetcon
Metabolic conditioning, usually high-density conditioning work.
Open termWOD
Workout of the day.
Open termPump
Temporary swelling and fullness in a muscle during or after training.
Open termMind-muscle Connection
The subjective focus on feeling a target muscle work.
Open termNatty
Natural, usually meaning no performance-enhancing drugs.
Open termEgo Lifting
Using loads or form that are too ambitious for the goal.
Open termNewbie Gains
Fast early progress seen in beginners.
- beginner gains
Shredded
Very lean and muscular appearance.
Open termJacked
Very muscular or strong-looking.
Open termSwole
Muscular, often exaggerated or humorous.
Open termPlate Math
The practice of calculating barbell loading with plates.
Open termGrinder
A rep that is completed very slowly and near failure.
Open termRep Out
To keep performing reps until the set ends.
Open termCheat Reps
Reps performed with body English or momentum.
Open termPartial Reps
Reps done through only part of the full range of motion.
Open termForced Reps
Extra reps helped by a spotter after the lifter reaches failure.
Open termNegative Reps
Reps emphasizing the eccentric phase.
- negatives
Burn Set
A very fatiguing set meant to create high local stress.
Open termFailure Set
A set taken to momentary muscular failure.
Open termSpotter
A person who helps keep a lift safe or assist if needed.
Open termDeload Week
A lighter week used to reduce accumulated fatigue.
Open termWarm-up
Pre-workout activity that prepares the body for harder work.
Open termCooldown
Easy movement or downshifting after training.
Open termPR
Personal record, your best result for a lift or performance metric.
Open termPB
Personal best, a record performance.
Open term