When trained men take longer breaks between weightlifting sets, they can lift heavier weights and still get just as strong as with shorter breaks, even if they do more total work over 6 weeks.

If two groups of young men lift weights with the same total effort but one rests longer with heavier weights and the other rests briefly with lighter weights, they both get just as strong after 8 weeks—even though you’d think the heavy weights would win.

If you lift weights more often each week, you’ll likely get stronger—but only up to a point. After a certain number of sessions, doing even more won’t help much more.

If you're already fit and lift weights, doing 5 to 10 sets per muscle group each week will make you stronger—but doing more than that (like 15 to 20 sets) won't make you any stronger, no matter how hard you push.

If you do the same total amount of weightlifting work, it doesn’t matter much if you rest 20 seconds or 2 minutes between sets—your muscles grow and get stronger about the same either way.

If you're new to lifting weights, doing a moderate amount of workouts each week will make you stronger faster than doing very few workouts — and you'll keep getting stronger week after week for the first 9 weeks.