Doing one set of strength training until your muscles are totally tired might help you jump higher than stopping two reps early, but we’re not sure if the difference really matters.

If you're already used to lifting weights, going all the way to failure on each set doesn't give you better strength or endurance gains than stopping two reps short — at least over 8 weeks.

When people lift weights until they're almost too tired to continue, especially with arm exercises, they get better at guessing how many more reps they could do. It's like training your body to feel its limits more accurately.

When people do more reps in a row during weight training, they become worse at guessing how many more reps they could do. This means longer sets make it harder to judge your own effort accurately.

You don’t have to push yourself to the absolute limit during strength training to get stronger—studies show you can make similar gains even if you stop a few reps short.

Whether you're new to lifting weights or have been doing it for years, you're just as good at guessing how many more reps you can do before your muscles give out.