How heavy should you lift?
How heavy should you lift when working out?
We generally recommend that you finish each set with about one or two reps in reserve.
For example, if you’re doing 10 bicep curls, you should feel by the time you get to the tenth rep like you could maybe do 11 or 12 total reps with good form.
If you feel like you could do 20 total reps with good form, you should try a heavier weight.
(Notice we’ve said “with good form” twice now?)
And if the tenth rep is a serious struggle, go a little lighter next time.
Unless you’re testing your one-rep max with a coach’s supervision, we don’t generally recommend going to failure, that is, until your muscles physically can’t lift the weight anymore. You’re more likely to lose form and injure yourself that way.
Focusing on form and finishing a set with one or two reps in reserve is a safer approach to building strength and muscle.

