Middle school students who take part in a greater number of sports are less likely to smoke than those who participate in fewer, a new study suggests. The researchers also found middle schoolers’ decision about whether to smoke is influenced by whether their teammates do so.

The influence of teammates’ smoking behavior is greater among girls than boys, HealthDay reports.

“This result suggests that peers on athletic teams influence the smoking behavior of others even though there might be a protective effect overall of increased participation in athletics on smoking,” study leader Kayo Fujimoto said in a journal news release.

The study included 1,260 sixth through eighth graders, who were questioned about their smoking behavior. The researchers asked the students to name friends at school, as well as the organized sports they participated in at school. They used a social network method they developed to evaluate how participation in sports with teammates who smoked affected the students’ own smoking behavior.

Fujimoto said that the findings suggest peer-led smoking prevention programs should be expanded to include sports teams.

The results are published in Child Development.