If older people don’t get stronger with light workouts, doing more sets of leg exercises might help them build more strength over 10 weeks.

If older people don’t get stronger from doing just one set of weight exercises, doing four sets instead might help them build more strength after training twice a week for 10 weeks.

If older people don’t get stronger with just one set of weight exercises, doing four sets instead might help them build more strength.

If older people don’t get stronger from doing just one or two sets of weight exercises, doing four sets might help them build more strength—but it doesn’t work as reliably as it does for making muscles bigger.

If older people who didn’t get stronger from doing just one set of leg exercises start doing four sets instead, they’ll likely see bigger thigh muscles after 10 weeks of training twice a week.

If you're an older adult who's already seeing some muscle growth from light weight training, doing more sets might help you build even more muscle—but the extra gain isn't big enough to be sure it's real and not just luck.