Those randomized to this condition focused on reducing their overall sitting time by two hours per day (a goal achieved in similar studies [17,18] that represented approximately a 25% reduction in daily sitting time). Participants were encouraged to reach this goal by standing in bouts of roughly 10 minutes per hour. The purpose of this arm was to investigate whether we could replicate improvements in sitting time achieved in other worksite studies in our cohort of older adults, which included both workers and non-workers.

Those randomized to the sit-to-stand condition focused on increasing the number of sit-to-stand transitions they performed throughout the day with a goal of adding 30 additional transitions per day. Previous studies have not succeeded in increasing the number of sit-to-stand transitions in older adults, possibly because they focused on reducing overall sitting time, encouraged longer standing breaks and did not provide a specific goal for sit-to-stand transitions [26-28]. An increase in sit-to-stand transitions would not be expected with an increase standing intervention alone, as prolonged standing reduces the opportunity for sit-to-stand transitions.

Participants were randomized to either reduce their total sitting time or increase sit-to-stand transitions. Information was provided in person, through written materials and by emails and phone calls in both conditions. Both groups received written educational materials on the dangers of excessive sitting and reviewed a generic day to illustrate how many sitting opportunities individuals face each day. During each session, the health educator also discussed the benefits of sitting less or increasing sit-to-stand transitions (depending on study condition) and brainstormed potential barriers to implementing the new behavior as well as strategies to overcome these barriers.

To determine the acceptability and feasibility of selected personal, social and environmental strategies to reduce overall sitting time and increase the number of times participants stand up in a day

To assess whether existing and new measurement approaches can detect specific changes in sedentary behavior.

To establish whether specified intervention strategies were efficacious in reducing sedentary behavior and whether intervention effects were specific to the targeted sedentary behavior construct (e.g. decreased overall sitting time or increased number of breaks in sitting).