Low-volume resistance training protocols can induce muscular hypertrophy but are generally suboptimal for maximizing muscle growth compared to moderate-to-high volume resistance training protocols.

Study: Is There Too Much of a Good Thing?

Doing more sets per workout generally builds more muscle, but after a certain point, adding extra sets stops making a big difference. This means light workouts can grow muscle, but heavier workouts are better for getting the most growth possible.

Study: The Resistance Training Dose Response: Meta-Regressions Exploring the Effects of Weekly Volume and Frequency on Muscle Hypertrophy and Strength Gains.

More sets and reps usually make your muscles grow bigger, but even a few sets can still help—just not as much as doing more. This study looked at lots of workouts and found that more volume = more muscle, but with diminishing returns.

Study: Higher volume resistance training enhances whole-body muscle hypertrophy in postmenopausal and older females: A secondary analysis of systematic review and meta-analysis of randomized clinical trials.

The study shows that while doing a small amount of weightlifting still builds muscle, doing more sets and reps leads to significantly bigger muscle gains, especially in older women.