Doing a rep.
In the gym, a rep (repetition) by itself doesn't make much change to your body.
But 12 reps can make a set and 3 sets count as one exercise. A workout typically comprises of 8 exercises. And if you get in 3 workouts a week in 12 weeks, your body changes.
What counts as a rep in your project? How can you get more of them in?