A REP is one complete repetition of an exercise.
A SET is a group of repetitions.
3 × 10 means:
3 sets of 10 repetitions.
Why do Rep Ranges Differ?
Different goals can favor different loading and repetition strategies.
Strength training generally uses heavier loads.
Muscle growth can be achieved across a relatively broad range of repetitions when sets are sufficiently challenging.
Beginners should not obsess over one magical rep number.
Focus on
- Good technique
- Appropriate resistance
- Enough effort
- Consistency
- Progressive training
Example
Goblet squat:
3 sets × 8 to 12 reps
If you can perform 12 good repetitions comfortably, your program may call for a small progression.