Why Fitness Jargon Matters
Walking into a group fitness class or picking up a structured workout plan for the first time can feel like learning a new language. Instructors call out cues like "keep your RPE around a seven" or "we're going into a superset now," and the expectation is that you'll just know what that means. You shouldn't have to guess.
This reference glossary defines the most common terms you'll encounter in fitness classes, gym programming, and workout apps — in plain language, with no assumed background. Think of it as a quick-lookup companion, not a textbook. Once the vocabulary clicks, you can focus on the actual work rather than decoding the instructions.
For context on how these terms connect to broader health habits, our nutrition fundamentals glossary covers the complementary language you'll encounter around eating and fueling activity.
Rep (Repetition)
One complete execution of an exercise movement from start to finish. Reps are counted to measure workout volume within a set.
Set
A group of consecutive repetitions performed without a rest break. Workout programs specify both the number of sets and reps.
RPE
Rate of Perceived Exertion — a self-assessed scale (typically 1–10) indicating how hard an activity feels. Used to guide effort intensity without requiring external measurement tools.
AMRAP
As Many Reps (or Rounds) As Possible within a set time period. A format designed to maximize work output while maintaining safe form.
EMOM
Every Minute On the Minute — a workout structure where a task begins at the start of each minute, and remaining time serves as rest.
Superset
Two exercises performed consecutively with minimal rest between them, followed by a rest period. Used to increase training efficiency or intensity.
Tempo
The prescribed speed of each movement phase, expressed in seconds. Controls how quickly you lower, pause, and lift during an exercise.
Progressive Overload
The principle of gradually increasing training demands over time to continue driving adaptation. Can be applied through weight, volume, rest reduction, or range of motion.
1RM
One-Rep Maximum — the maximum load that can be lifted for a single repetition with proper form. Used as a reference point for setting training weights.
Compound Exercise
A movement that engages multiple muscle groups and joints at once, such as a squat or deadlift. Generally considered more efficient for building overall strength.
Eccentric Phase
The portion of a movement where the muscle lengthens under load — typically the lowering phase. Controlled eccentric movement is important for strength and injury prevention.
Time Under Tension (TUT)
The total duration a muscle is loaded during a set. Longer TUT, often achieved through slower tempo, is associated with muscle growth stimulus.
Core Training Concepts
These terms describe how workouts are structured and measured. You'll see them in written programs, on fitness apps, and in class descriptions.
| What does RPE stand for? | Rate of Perceived Exertion — a 1–10 self-reported effort scale |
| What is AMRAP? | As Many Reps (or Rounds) As Possible in a fixed time |
| What is a superset? | Two exercises performed back-to-back with minimal rest between them |
| What does tempo mean in workouts? | The prescribed speed (in seconds) for each phase of a movement |
| What is progressive overload? | Gradually increasing training demand over time to drive continued adaptation (General exercise science consensus) |
| What does EMOM mean? | Every Minute On the Minute — work starts at the top of each minute |
Rep, Set, and Rest
A rep (repetition) is one complete movement — one squat, one push-up. A set is a group of consecutive reps performed without stopping. Rest is the recovery period between sets. A program might call for "3 sets of 10 reps" with 60 seconds of rest between sets.
Superset
Two exercises performed back-to-back with little or no rest between them before taking a rest period. Supersets can pair opposing muscle groups (like biceps and triceps) or the same muscle group for added intensity.
AMRAP
As Many Reps (or Rounds) As Possible within a fixed time window. Common in CrossFit-style workouts and circuit formats. The goal is to complete as much work as you can with good form — not to rush at the expense of technique.
EMOM
Every Minute On the Minute. You start a set number of reps at the top of each minute; whatever time remains in that minute is your rest. EMOM workouts build pacing discipline alongside conditioning.
Tempo
The speed at which you perform each phase of a movement, usually written as a four-digit code (e.g., 3-1-2-0). The digits represent seconds for each phase: lowering, pause at the bottom, lifting, and pause at the top. Slowing tempo increases time under tension, which can support muscle development.
Time Under Tension (TUT)
The total time a muscle is actively working during a set. Longer TUT (often achieved through controlled tempo) is associated with muscle growth stimulus, though overall training volume and effort remain the most important variables.
Progressive Overload
Gradually increasing the demand placed on the body over time — through more weight, more reps, shorter rest, or greater range of motion. This principle is foundational to long-term fitness improvement.
If you're exploring how different training formats apply these concepts, see our comparison of HIIT, circuit training, and interval workouts.
Effort, Intensity, and Movement Terms
RPE (Rate of Perceived Exertion)
A self-reported scale — commonly 1 to 10 — rating how hard an exercise feels. An RPE of 5 might feel like a brisk walk; an RPE of 9 is near-maximum effort. Using RPE helps you regulate intensity relative to how your body feels on a given day, rather than relying solely on fixed weights or speeds.
1RM (One-Rep Maximum)
The maximum weight you can lift for a single rep of a given exercise with good form. Programs often prescribe loads as a percentage of your 1RM (e.g., "work at 75% of your 1RM"). Beginners should estimate rather than test 1RM directly; near-maximal lifts carry injury risk without appropriate experience and supervision.
A Note on Testing Your 1RM
Attempting a true one-rep maximum lift carries injury risk, particularly for those new to resistance training. Many coaches recommend using a rep-based estimation formula instead — for example, lifting a weight you can move for several reps and using a calculation to approximate your maximum. If you're newer to strength training, work with a certified coach or personal trainer before attempting near-maximal loads.
Compound vs. Isolation Movements
Compound exercises engage multiple muscle groups and joints simultaneously — think squats, deadlifts, and rows. Isolation exercises target a single muscle group, such as a bicep curl. Most balanced programs incorporate both.
Concentric and Eccentric
The two main phases of a muscle contraction. The concentric phase is when the muscle shortens (the "lifting" phase of a curl). The eccentric phase is when the muscle lengthens under load (the "lowering" phase). Eccentric control is a key factor in strength development and injury prevention.
Warm-Up and Cool-Down
A warm-up prepares the body for exercise — raising heart rate, increasing blood flow to muscles, and moving joints through their range. A cool-down allows the body to gradually return to rest. Both are associated with better performance and reduced injury risk, according to general sports science guidance.
This article is for general informational purposes only and does not constitute medical or fitness advice. Consult a qualified healthcare or exercise professional before beginning or changing any physical activity program, especially if you have an existing health condition or injury.
