If you're lifting weights and go all the way to muscle failure, doing between about 6 and 35 reps per set can help you build muscle just as well as lower reps.

You can still build muscle even if you don't push your sets to within five reps of total failure, which goes against the idea that only the last few tough reps really matter for growth.

If you mix up your workout reps—sometimes doing just a few, sometimes a bunch—your muscles grow about as much as if you always stuck to the usual 8 to 12 reps per set.

Doing around 31 sets per muscle group each week is the sweet spot for building muscle, and doing more than that won't give you noticeably better results.

Progressive increases in strength within the 6–12 repetition range under consistent training conditions are a reliable proxy for skeletal muscle hypertrophy.

If you're already someone who lifts weights, doing light weights twice a week until you can't do more reps can make your muscles bigger and stronger in just 8 weeks.