The purpose of the study is to learn more about effective ways to motivate people to increase their non-exercise energy expenditure exercise. This is an important research question because obesity and weight-related issues are increasingly becoming a problem in America. This project will address this research question by testing the effect of group dynamics in motivating employees who are predominantly sedentary to use Walkstations at work. The Walkstations are treadmills that move at a very slow rate (maximum 2miles / hour) and are attached to a work station (i.e. with computer and telephone); they therefore are designed to increase energy spent not through heavy exercise, but through small changes in posture and movement associated with routines in daily life (called nonexercise activity thermogenesis or NEAT). The proposed study is designed to build upon previous research (Levine et al., 2005) suggesting the role of NEAT-enhanced behaviors in weight loss.

In this study, the investigators are interested in the impact of group dynamics on the propensity to use the Walkstations. Participants in the active arms will be asked to use the Walkstations for at least 3 hours per week. They will do so by signing up for a time slot. During their session, they will be asked to log into the scheduling system to indicate that they are using the Walkstation. Walkstation usage will be assessed by log-in data: employees will log-in to the phone and computer when they use the Walkstation. This log-in data is work-station specific; therefore the investigators will be able to tell when a given subject used the Walkstation.

Subjects will be randomly assigned to one of three conditions:

1. Individual. In the individual condition, participants will not be part of a team. They will receive weekly email feedback on their Walkstation performance (e.g. number of time slots they signed up for, and number of times they showed up for the time slot.) Participants will also receive a wellness tip in each email. (see appendix for a sample email)
2. Pairs. In the pair condition, participants will be randomly assigned to a partner. They will receive the same feedback as those in the individual condition, for both themselves AND their partner.
3. Group. In the group condition, participants will be randomly assigned to a group of 5 people. They will receive the same feedback as those in the individual condition, for both themselves AND each member of their group.

Inclusion Criteria:

• Must pass the ParQ
• Must be employee of BCBS Massachusetts

Exclusion Criteria:

• Failing the ParQ
• Not being an employee of BCBS Massachusetts