Crystal Smit

Chapter 5 94 ABSTRACT There is a need to develop and improve interventions promoting healthy drinking behaviors among children. A promising method could be to stimulate peer influence within children’s social networks. In the Share H 2 O social network intervention, peer influence was utilized by selecting a subset of influential children and training them as ‘influence agents’ to promote water consumption—as an alternative to sugar-sweetened beverages. Previous research has mainly focused on the process of selecting influence agents. However, the process of motivating influence agents to promote the behavior has hardly received any research attention. Therefore, in the Share H 2 O social network intervention, this motivation process was emphasized and grounded in the self-determination theory. This study evaluated the implementation of the Share H 2 O social network intervention, focusing on whether and how applying self-determination theory-based techniques canmotivate the influence agents and, indirectly, their peers. The study included data collected in the Netherlands from both the influence agents ( n = 37) and the peers ( n = 112) in the classroom networks of the influence agents. Self- reported measurements assessed the influence agents’ enjoyment of the training, duration and perceived autonomy support during the training, and changes in their intrinsic motivation and water consumption before and after the start of the intervention. Changes in the peers’ intrinsic motivation, perceived social support, and social norms were measured before and after the start of the intervention. Results showed that the influence agents enjoyed the training, considered the duration to be adequate, and perceived the training to be autonomy supportive. There was an increase in the influence agents’ intrinsic motivation to drink water and their actual water consumption. Providing personal meaningful rationales seemed to have motivated the influence agents. The intrinsic motivation and perceived descriptive norm of the peers remained stable. The peers reported an increase in their perceived social support and injunctive norm concerning water drinking after the intervention. Influence agents appeared to mainly use face-to- face strategies, such as modeling, talking to peers, and providing social support to promote the behavior. The current findings provided preliminary evidence for the