Soccer star Lionel Messi wears cleats inscribed with his son's name and part of Argentina's flag. The cleats of Austrian star David Alaba have a Nigerian flag in honor of his father and say, “Jesus loves u.” But do these personal touches help them play better? Research suggests that may be the case.

In several studies in an upcoming issue of the Journal of Marketing Research, students worked and played better when using items they had decorated to portray aspects of themselves. Even though participants did not expect any benefit, they threw customized darts more accurately, they came up with more anagrams using a customized pen, and they played a beer-coaster flipping game better with customized coasters. Across the studies, customization boosted performance by 25 percent.

The trick worked best when people cared about doing well and when the decoration embodied a task-relevant part of their identities (for example, decorating a coaster with a drawing of a competitive athlete will help you more in a flip game than will drawing a picture of people holding hands). “If there is an alignment between the goal and the identity, then you are more motivated to pursue this goal because you can affirm this part of the identity,” says Martin Schreier, one of the study's authors and a professor of marketing at the Vienna University of Economics and Business in Austria. Indeed, when people did well with their custom coasters, it actually strengthened that aspect of their personal image—as if player and coaster had become one.

So, Schreier says, first make sure your gear suits you functionally, then put yourself into it expressively.