Sets, reps and rest

“3 × 8–12” means 3 sets of 8 to 12 repetitions. Rest the stated time between sets.

The words

• Rep (repetition): one full movement, e.g. one squat down and up.
• Set: a group of reps done without stopping.
• Rest: the break between sets. Start the timer when you finish a set.
• Range (8–12): you aim to land anywhere in it with good form. When you can do the top of the range on every set, the weight goes up.

How much for beginners

For novices, the American College of Sports Medicine recommends training each major muscle group 2–3 days a week with full-body sessions, using 1–3 sets per exercise [1]. For general health, adults should do muscle-strengthening activity at least 2 days a week, alongside cardio [2].

Rest of 1–2 minutes suits most beginner work; heavy lower-body sets can use 2–3 minutes [1].

How hard should a set feel?

The last two reps should be hard but clean. If your form breaks down, the set is over, even if you haven’t reached the number.

Do reps matter for muscle?

Across studies, muscle growth was similar with heavy and light loads when sets were taken close to failure; heavier loads gave bigger strength gains [3]. So the range you choose depends more on your goal than on a magic number. See Goals.