For young women, lifting lighter weights can be just as good as lifting heavier ones for building muscle and getting stronger, as long as you do the same total amount of work.

For young women, doing lighter weightlifting for 10 weeks can build leg muscle just as well as heavier lifting, with muscle growth between 3% and 12%.

Lifting heavier weights with proper form was better than lifting lighter weights for building both muscle strength and size in men after 3 months of training.

For young women lifting weights, how much total work you do might matter more for building muscle and strength than how heavy the weights are, because studies show similar results when the total effort is the same but intensity differs.

If you're a woman who's already been working out, doing 5 to 10 sets of strength training per muscle group each week seems to be enough to build muscle and get stronger over half a year — doing more doesn't seem to help extra.

Doing just one set of each exercise can still help build muscle, even if you're already fit — and it saves time.