If you’re already experienced with weightlifting, doing either kind of set—short breaks or long continuous sets—will make your muscles grow, as long as you’re working hard and doing the same total amount of work.

When people who already lift weights do either short breaks between reps (cluster sets) or long continuous sets (traditional sets), both ways make their muscles grow about the same amount if they work just as hard and do the same total number of reps.

If you lift weights with either light weights and short breaks, or heavy weights and long breaks—but keep the total work the same—you’ll still build muscle in about 8 weeks. So, there’s more than one way to get stronger and bigger muscles.

Higher weekly resistance training volume leads to greater muscle hypertrophy in trained individuals.

If you're already experienced with weight training, doing 5 to 10 sets per muscle group each week builds just as much muscle and strength as doing 15 to 20 sets—so going over 10 sets won't give you extra gains.

If you’re already experienced with weightlifting and train your legs twice a week for 8 weeks with hard sets, your muscles will grow whether you take short breaks between reps or not.