Whether it’s hitting a killer first serve or doing an Olympic lift, it pays to keep practicing even after you think you’ve got it down pat.

A recent study from the journal Nature Neuroscience found that to cement your skill and create a shift in the part of the brain where learning occurs, you need to do it about 20 minutes past the point of mastery. The authors of the study call this “overlearning,” which is pretty self explanatory.

The researchers started the study by giving a group of testers a visual-recognition test—it was found that the testers understood how the test worked after about eight rounds of practice. Then, the next group of testers were split in two: Group A was given one task that they practiced for eight rounds, took a 30 minute break, and then did a similar task for another eight rounds. In contrast, Group B was given 16 rounds of practice for the first task (or double the amount of practice they would normally need to learn it), while the second test was the usual eight rounds. The researchers found that Group B did significantly better on the first task than Group A, while on the second task Group A did better while Group B stayed the same. When the researchers repeated the test but increased the break time between tasks from 30 minutes to 3.5 hours, the group that experienced overlearning improved in both tasks instead of just the first.

The takeaway? “Overlearning” helps solidify new skills to memory, though you may want to spread out your time between learning new workouts. Without overlearning, your brain may “overwrite” skills you’ve already learned with new skills, especially if you’re learning the skills in quick succession.