I'm thinking more along the lines of practicing different scales, arpeggios and pieces each time, and practicing several different things instead of repeatedly practicing a single thing. Unfortunately, though, as an amateur violinist, I can say that this approach is not all that feasible after a certain level. Varying your warm-ups like what scales, arpeggios and etudes you play might be a good idea, but in the end the only really effective way of mastering a piece is to play it over and over, mostly in small sections, until you get it right. If you just scim over it each time, you're probably going to let mistakes slip in and ferment. But maybe changing something less related to the actual activity more in line with what you suggested might also work - lowering and raising the music stand and piano stool or chair, changing instruments or location, etc.