Effect of team competitions on participation and adherence to an Internet-mediated physical activity program

Internet-mediated interventions aimed at increasing physical activity are becoming increasingly popular; however, little is known about their effectiveness. Active U is an eight-week automated Internet-mediated physical activity intervention that incorporates physical activity tracking, team competition, motivational emails, and goal setting to promote physical activity. Participants joined Active U as an individual or as a member of a competitive team. This study sought to determine whether or not participation on a team increased individual success with the program.

The Active U intervention recruited 7,520 graduate students, staff, and faculty members from the University of Michigan during the winter of 2007 through an intensive publicity campaign. Zero inflated Poisson regression models with two different outcomes were developed: the number of weeks that physical activity was entered into the Active U tracker and the number of weeks that physical activity goals were met.

Overall, 5,166 participants (69%) used the physical activity tracker at least once during the intervention. Individuals who joined competitive teams were more likely to use the physical activity tracker (IRR=1.27, p<.001). In addition, participants on competitive teams were less likely to never have met their weekly goals than those who did not join teams (OR=0.37, p<.001). Finally, individuals on teams with 10 to 14 members met their goals more often than participants on either smaller or larger teams (IRR=1.20, p=.012). Thus, individuals who participate in team competitions in an Internet-mediated physical activity program, particularly teams of 10 to 14 participants, have better outcomes than those participating individually.