"I think the findings have real-world applications, such as using avatars in video games to 'nudge' people to increase physical activity," said one of the researchers Jorge Pena from the University of California, Davis in the US.
The study was published in the Journal of Computer-Mediated Communication.
The researchers conducted an experiment where participants were randomly assigned to a normal weight or obese avatar as well as normal weight or obese opponent in a virtual tennis game.
The avatar and the opponent were essentially the same male virtual character.
The body size of the avatar was manipulated by setting a different Body Mass Index (BMI) for the normal or obese virtual character.
The normal weight character was thin and had a BMI of 18.6 (where normal range BMI is 18.5 to 24.9). The obese character had a BMI of 32.1.
The researchers found that regardless of participants' own BMI, those using thin avatars showed increased physical activity compared to those using obese avatars.