Setting and Participants
A total of 66 office workers were recruited in clusters from the Massachusetts General Hospital and Northeastern University in Boston, Massachusetts (ie, Massachusetts General Hospital: 19 clusters; n=60, 91%; Northeastern University: 5 clusters; n=6, 9%). These clusters were randomized into the following groups: seated desk control (21/66, 32%; 8 clusters), sit-to-stand desk (23/66, 35%; 9 clusters), and treadmill desk intervention (22/66, 33%; 7 clusters) groups. Participant clusters were identified based on office space, such that clusters were separated by walls or were located on a different floor or building. Separations were aimed at preventing participants in one cluster from being visible to other clusters during day-to-day office activities. Employees within these clusters were considered eligible if they were employed in a full-time seated desk job, were aged between 18 and 65 years, had a BMI of >25 kg/m