A study found that for women new to weightlifting, doing many reps with lighter weights or fewer reps with heavier weights both built muscle and strength equally well over 8 weeks.

For women who don't usually lift weights, doing lots of lighter reps or fewer heavy reps both build similar muscle size and make you stronger after two months.

For women new to weight training, doing either many lighter reps or fewer heavier reps for 8 weeks gives about the same muscle growth in the thigh muscles, showing both methods work well for beginners.

Most of the research on how much to lift and how often was done on young men who already train—so we don’t know if the same rules apply to women, older people, or beginners.

When women who haven't trained before do weightlifting for 8 weeks, they get much stronger (27-43% stronger) but their muscles don't grow much (only 3-4% bigger), showing that getting stronger happens faster than building bigger muscles at the start.

Doing more weightlifting each week helps you build more muscle—but only up to a point. After a certain number of sets, doing even more doesn’t help much more.