Impact of social support intensity on walking in the severely obese:: A randomized clinical trial

Objective: There are few established methods for promoting physical activity (PA) in the severely obese. Because social support is a potential method for promoting PA, we compared mean steps/day during 18 weeks in severely obese outpatients receiving either standard support (SS) or added support (AS). Methods and Procedures: Eighty severely obese outpatients from an obesity clinic were invited; 66 provided written consent, 55 were randomized, and 42 were included in final analyses (9 men, 33 women; age 44.4 +/- 13.1 years; BMI 41.9 +/- 5.5 kg/m(2)). All participants received a pedometer and a walking promotion booklet. In addition to SS, the AS group received ten 2-h group counseling sessions aimed at increasing weekly accumulated steps, every second week during the study. Each participant was asked to complete a 7-day walking diary every second week (10 observations). Results: Baseline steps/day was 6,912 for the AS group and 5,311 for the SS group (P = 0.023). Data at 18 weeks showed that the AS group recorded 10,136 steps/day and the SS group 6,118 steps/day (P = 0.024). There was no allocation x time interaction (P = 0.46). During the follow-up period as a whole, the AS group recorded 1,794 more steps/day than the SS group (P = 0.0074). Discussion: The AS group recorded more steps/day than the SS group, reaching a mean level of similar to 10,000 steps/day. However, the nonsignificant interaction between allocation x time suggests that this difference was present already at baseline and did not increase during follow-up.