Every gym has its own shorthand — AMRAP, RIR, drop sets, deload. Here's a plain-English glossary of the most common weightlifting terms, defined in one or two sentences so you can decode any program, app or coaching cue without guessing.
This is a plain-English glossary of the weightlifting terms you'll actually run into — set and rep basics (rep, set, superset, drop set, cluster set), progression ideas (progressive overload, double progression, deload, periodization), effort measures (RPE, RIR, failure), movement types (compound, isolation, eccentric, concentric, isometric), and nutrition phases (cutting, bulking). Each term gets a one- or two-sentence definition; where a concept has its own full guide, it's linked inline. Use it as a quick reference whenever a workout throws a word you don't recognize.
One complete execution of an exercise — lowering and lifting the weight through the full movement once. Reps are the smallest unit of a workout; several done in a row make a set.
A group of consecutive reps performed without resting, followed by a rest period. A workout is usually written as sets × reps, for example 3 × 8 meaning three sets of eight reps.
The heaviest weight you can lift for a single rep with good form on a given exercise. It's a common benchmark for strength and the basis for percentage-based programs.
Short for "As Many Reps As Possible" — a set where you perform as many quality reps as you can at a set weight, usually stopping a rep or two short of a form breakdown. Some programs use an AMRAP set to gauge progress.
Two exercises performed back to back with no rest in between. Supersets save time and can raise intensity; pairing opposing muscles (like biceps and triceps) is a common approach.
A set taken close to failure, then immediately continued at a lighter weight to squeeze out extra reps. It's an intensity technique used mainly to add volume and fatigue for muscle growth — see the full drop sets guide.
A set taken near failure, then continued after very short rests (often 10–20 seconds) to accumulate more reps at the same weight. It packs extra work into one heavy set.
A single set deliberately broken into small mini-sets with brief intra-set rests. The short breaks let you handle heavier loads for more total quality reps than one continuous set would allow.
A lighter, submaximal set done before your working sets to prepare the muscles and joints and groove the movement. Warm-up sets don't count toward your hard training volume.
A challenging set performed at your target weight that actually drives adaptation, as opposed to a warm-up. When people talk about "3 sets" of an exercise, they usually mean working sets.
The principle of gradually increasing the demand on your muscles over time — usually more weight or reps — so they keep adapting and getting stronger or bigger. It's the core idea behind almost every gain; read the full progressive overload guide.
A simple progression method: keep the weight fixed and add reps within a target range first, then once you hit the top of the range on every set, add weight and reset the reps to the bottom.
A planned lighter week of reduced weight or volume that lets accumulated fatigue clear so you recover and can keep progressing. It's scheduled recovery, not a break — see the deload guide.
Organizing training into phases over weeks or months — varying volume, intensity and focus — to manage fatigue and keep making progress instead of stalling. Learn more in the periodization guide.
The total amount of work you do, generally counted as sets × reps × load over a session or week. Rising volume over time is a primary driver of muscle growth, so many lifters track weekly sets per muscle.
How often you train a given muscle group or lift, usually measured as sessions per week. Spreading volume across more frequent sessions can make each one more productive.
A slightly submaximal weight, set a little below your true 1RM, used as the number that program percentages are based on. Working from a training max keeps prescribed weights realistic and repeatable.
Your best-ever performance on a lift — a new heaviest weight, most reps at a weight, or best estimated max. PRs are the clearest sign that progressive overload is working.
A 1-to-10 rating of how hard a set felt, used to gauge and regulate effort. An RPE 8 roughly means you had two reps left before failure; it lets you push harder on good days and back off on bad ones — full RPE guide.
How many more reps you could have done before hitting failure at the end of a set. It's the mirror image of RPE — 2 RIR is about an RPE of 8 — and a straightforward way to keep sets challenging but safe; see the RIR guide.
The point in a set where you can no longer complete another rep with proper form. Training to failure is one tool for stimulus, but doing it on every set adds fatigue that can slow recovery.
The controlled speed of each phase of a rep, often written as four numbers for the lowering, bottom pause, lifting and top pause. Slowing the tempo adds time under tension without adding weight.
An exercise that works multiple muscle groups across more than one joint — squats, deadlifts, bench press, rows and overhead press. Compounds build the most strength and are usually the backbone of a program.
An exercise that targets a single muscle across one joint, like a biceps curl, leg extension or lateral raise. Isolation work is used to bring up specific muscles or add volume.
A supporting exercise done to strengthen weak points, balance a physique, or add volume beyond the main lifts. Accessories are usually lighter isolation or smaller compound movements.
How far a joint or limb travels through an exercise, from full stretch to full contraction. Training through a full, controlled ROM generally provides more stimulus than cutting the movement short.
The lowering or lengthening phase of a rep — for example, descending in a squat or lowering the bar to your chest. Muscles can control more weight eccentrically than they can lift.
The lifting or shortening phase of a rep — standing back up out of a squat or pressing the bar away from your chest. It's the phase where the muscle actively contracts to move the load.
A muscle contraction with no movement, holding a position under tension — like a plank, a wall sit, or pausing mid-rep. Isometrics build stability and control at a specific joint angle.
The growth of muscle size in response to resistance training. It's driven mainly by challenging volume and progression over time — see how to train for it in the build muscle guide.
The muscle soreness that shows up a day or two after training, especially after new or unusually hard work. Some soreness is normal, but it's a poor measure of how good a workout was.
A phase of eating in a calorie deficit to lose body fat while training to keep as much muscle as possible. Lifters often alternate cutting phases with bulking phases.
A phase of eating in a calorie surplus to support muscle and strength gains. A slower, controlled surplus limits how much extra fat comes along with the muscle.
1RM stands for one-rep max — the heaviest weight you can lift for a single rep with good form on a given exercise. It's a common benchmark for strength and for setting training percentages.
RPE is Rate of Perceived Exertion, a 1-to-10 rating of how hard a set felt. An RPE 8 means you had about two reps left in the tank; it's used to regulate effort day to day. See the RPE guide.
RIR means Reps in Reserve — how many more reps you could have done before failure at the end of a set. It's the mirror image of RPE: 2 RIR is roughly an RPE of 8. See the RIR guide.
A compound lift works several muscle groups across more than one joint, like a squat or bench press. An isolation exercise targets a single muscle across one joint, like a biceps curl.
A deload is a planned lighter week of reduced weight or volume that lets accumulated fatigue clear so you can recover and keep progressing afterward. See the deload guide.
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This is a plain-English reference and not medical advice. Consult a qualified coach or medical professional before starting or changing a training program.
By Meitar Lazimi, founder of LiftHero · Last updated July 9, 2026.