Sets
A set is a group of consecutive repetitions of an exercise performed before stopping to rest or moving to another exercise. In "3 sets of 8 reps," you perform eight repetitions, pause, and repeat that sequence twice more. Sets organize an exercise into manageable bouts and are one of the main units used to prescribe and record strength training.
Not every set has the same purpose. Warm-up sets prepare you for the movement and heavier loads, whereas working sets provide the main training practice or stimulus. A straight set is completed and followed by a normal rest interval; methods such as supersets, drop sets, and rest-pause sets arrange the work differently. A set may contain one repetition, many repetitions, or even a timed effort, depending on the exercise and goal.
Set count is a useful but incomplete measure of training volume. Three challenging sets are not necessarily equivalent to three easy sets, and sets of different exercises may not train a target muscle to the same degree. Load, repetition count, range of motion, technique, and proximity to failure all affect what a set demands and what adaptation it is likely to support. Warm-up sets are therefore usually recorded separately rather than counted toward weekly working-set volume.
When comparing workouts, define what you are counting. "Ten chest sets per week" normally means sets intended to train the chest, not every set in an upper-body workout. Compound exercises also complicate counting: a bench-press set primarily trains the chest while also loading the triceps, but its contribution to each muscle is not identical. Consistent definitions make set totals more useful than false precision.