Reps and sets, explained: what 3x10 means, and how to read the rest of a program

A rep, short for repetition, is one complete lift: down and up once. A set is a group of reps done in a row before you rest. So a program line like "squat 3x10" means three sets of ten squats, with a rest after each set. Everything else in a program is a variation on those two numbers, and this page reads them one by one. The terms on their own are in the training glossary.

How to read sets x reps

The first number is sets and the second is reps. 3x10 is three sets of ten; 4x8 is four sets of eight; 5x5 is five sets of five. Unless the program says otherwise, every set uses the same weight. A program that changes the weight from set to set usually says so, or writes it as pyramid sets.

RPE and RIR are two ways of writing the same thing. On the reps-in-reserve scale used in strength research, RPE 10 means no reps left and RPE 9 means one left, and so on down.¹ So RPE 8 is about two reps left. How to judge it from inside a set: reps in reserve.

How to pick the weight for 3x10

The two numbers tell you the work, not the weight. For 3x10, pick a weight you could lift for about twelve: ten reps with two or so left. That matches the 2026 American College of Sports Medicine stand, which says sufficient effort can come from sets near failure or a target of 2 to 3 reps in reserve.² Percentage charts are a starting point, not an answer: a 2024 meta-regression of repetitions-to-failure tests from 269 studies found the number of reps people manage at a given percentage of their one-rep max varies between individuals and between exercises, with separate tables for the bench press and the leg press.³ So the first session is a test: if the tenth rep of the first set was easy, go up next set; if you couldn't reach ten, go down. More on how much weight to lift, and the one-rep max calculator if you want a starting estimate.

Do all three sets have to be ten?

Not always. At the same weight, reps can fall from the first set to the last, and more so when sets go all the way to failure: in a 2024 eight-week trial in 18 trained lifters, repetition loss was consistently greater when sets went to failure than when they stopped 1 or 2 reps short.⁴ If the program says 3x10 and you get 10, 10 and 8, write that down and keep the weight until all three reach ten. If the program gives a range, 3x8-12, any number inside it counts.

Sets or reps: which matters more?

For counting how much training you've done, sets. A 2021 systematic review of 14 studies concluded that the total number of sets taken to or near failure seems to be an adequate way to quantify training volume for muscle growth when reps fall between 6 and 20 or more.⁵ A 2017 meta-analysis of 15 studies found that each additional weekly set went with a little more muscle growth.⁶ So weekly hard sets per muscle are the number to track: how many sets per week.

The rep number decides more about what kind of strength you build. A 2017 review of 21 studies found heavier loads built more one-rep-max strength, while muscle growth was similar across loads when sets went to failure.⁷ The ranges by goal: how many reps.

Common questions

Is 3x10 a good workout?

It's a reasonable default, not a magic number. Ten reps sits in the 8 to 12 range the 2009 ACSM stand recommends for novices,⁸ three sets sits inside the 2026 stand's 2 to 3 sets for strength,² and a 2021 review argues that muscular adaptations can be obtained across a wide spectrum of loads.⁹ What decides whether it works is how hard the sets are and whether the weight goes up over time.

Is 3 sets of 10 enough to build muscle?

Count it by the week. The 2026 stand found muscle growth enhanced by 10 or more sets a week,² so three sets for a muscle, two or three times a week, plus the other exercises that work it, reaches that count. The rest of the plan: how to build a workout plan.

Do warm-up sets count?

Not toward the sets in the program. 3x10 means three working sets; the lighter sets before them are extra. How many and how heavy: the warm-up set calculator.

How long should I rest between sets?

If the program doesn't say, the 2009 ACSM stand pairs muscle-building sets with 1 to 2 minutes of rest and heavy strength sets with 3 to 5.⁸ The full picture: how long to rest between sets.

If you'd rather have the numbers chosen for you

Reading the shorthand is the easy part; choosing the numbers for your week, and changing them when a lift stalls, is the part people get stuck on. Coaching is the version where your program is written around the days you actually have, and a weekly call looks at your logbook and adjusts the plan. How coaching works explains it, and apply is the first step. Otherwise: pick one exercise, do 3x10, and write down what you lifted.