After 10 weeks of hard lifting, your arms only get a tiny bit bigger — less than the thickness of a penny — no matter which method you use.

Doing regular weightlifting reps with full rest between sets builds a tiny bit more arm muscle than doing drop sets on a smart machine, but the difference is so small it doesn’t really matter in real life.

When young men who don't work out start doing arm exercises twice a week for 10 weeks, their biceps get about 6% bigger.

Young guys who took a break from working out didn’t see much muscle growth in certain areas—like the middle of the outer thigh and upper arm—after nine weeks of doing the same strength exercises.

When young men who haven't trained before do arm exercises twice a week for about 2 months, their biceps and related muscles grow by about 6% on average.

Even though guys doing drop sets did only one set instead of three, their muscles grew just as much or more than those who did three sets.