If you're already an experienced lifter, just adding more sets to your workouts won't keep making your muscles grow bigger. After a certain point, your body stops responding to extra volume, so doing more sets won't give you more muscle.

Doing more sets at the gym than you're used to—like going from 18 to 33 sets a week per muscle group—doesn’t make your muscles grow significantly more, even though you might see a little more growth overall.

Everyone’s body responds differently to workouts—what works wonders for one person might be too much or too little for another, because of differences in genes, energy use, and how fast they recover.

If you lift weights, your muscles grow bigger — but only up to about 45 sets a week per muscle group; after that, you don’t get much extra growth no matter how much more you train.

If you are already experienced with weightlifting, working out your muscles more often each week might help you build more muscle than just lifting heavier weights or doing more sets.

If you're new to lifting, doing just a few sets per workout might be enough to build upper body muscle — doing more sets probably won't give you much extra benefit.