When it comes to sports, forming rivalries with opponents could motivate you to perform better, says a study.
Runners ran faster in the races featuring their rivals, the findings showed.
"We may be able to boost our own levels of motivation and performance by either forming rivalries or harnessing the ones we already have," said Gavin Kilduff of New York University's (NYU) Stern School of Business.
"It might also get us to think about whether other individuals in our lives may view us as their rivals," Kilduff added.
Rivalries are distinct from other competitions as those involved place higher stakes on their performance independent of any tangible outcomes.
Kilduff took two approaches to studying rivalries: First, he surveyed people online about their feelings toward rivals, as well as characteristics of the rivalries.
Then, he analysed results from 184 races over a six-year time period in a US running club to try to identify rivalries and to match them to changes in performance over time.
The races ranged from three to 21 km.
Results of past contests can make people more motivated in future ones, the researcher found.
"How we behave in competition situations depends on our relationship and history of interaction with our opponent," Kilduff added.
The study appeared in the journal Social Psychological and Personality Science.