[Effects of a weight loss program with group participation supported by strengthened social support]

The purpose of this study was to examine the efficacy of a weight loss program with group participation supported by strengthened social support (hereafter termed the Weight Loss Rally).

Thirty-eight groups (41 males, 73 females) with a BMI of more than 22 kg/m2 living or working in Shizuoka Prefecture participated in the Weight Loss Rally. In order to strengthen social support, group participation approaches were taken instead of an individual participation approach. In the Weight Loss Rally, the weight changes of each group were monitored for twelve weeks with a goal of reducing 5% of their initial weight. In addition, the average steps taken per day, the average achievement rate for exercise, and attainment of diet objectives were assessed at the same time. All evaluations with other characteristics, such as remuneration and communication systems, were made on a group rather than an individual basis. In order to confrim the benefit of the Weight Loss Rally, physical measurements of all participants were taken and questionnaires were administered before and after the program.

Complete data were obtained for 32 groups (35 males, 61 females). An average of 3.7 kg weight loss was observed for a total of 96 men and women (92.7%) along with increase of physical activity and decreased dietary intake (P < 0.001). An average of 1.4 kg/m2 decrease in BMI, an average of 2.8% decrease in body fat percentage, and an average of 3.9 cm reduction in waist circumference were reported (P < 0.001). According to the results of the questionnaires, 91 participants (94.8%) answered that they felt comfortable with the group participation toward the Weight Loss Rally. Other grouping methods were also used to analyze the results. First, group of colleagues, friends and family members were compared. Second, males, females and mixed groups were also compared for analysis. For every group similar results such as decrease in weight, BMI, body fat percentage, and waist circumference were recognized (P < 0.05).

Eighty-eight participants out of 96 reported effective loss of body weight. Social support apparently played an important role. For that reason, this new Weight Loss Rally with group participation and social support could be an effective method for attaining weight loss for many people.