The Influence of Behavior Self-Monitoring Using Technology on Weight Loss in Overweight Adults

Abstract

The BodyMedia® FIT System (BodyMedia Inc.) is a commercially available tool that includes a multi-sensor armband, a display that provides real time feedback of energy expenditure and physical activity, and is integrated with a website that allows for monitoring of energy intake and body weight. It is unclear if use of these self-monitoring components are predictive of weight loss. PURPOSE: To examine which of the monitored energy balance variables using the BodyMedia® FIT System (wearing the multi-sensor armband, self-monitoring of energy intake, self-monitoring of weight) was predictive of weight loss in overweight and obese adults. METHODS: Thirty overweight and obese adults (BMI: 33.9±3.5 kg/m2; Age: 44.2±8.7 yrs) were randomized to one of two groups: standard in-person group-based behavioral weight loss with the addition of the BodyMedia® FIT System (SBWL+TECH), or the BodyMedia® FIT System plus one brief telephone contact per month (TECH). Energy intake was prescribed at 1200-1800 kcal/d and physical activity progressed to 300 min/wk. Weight was assessed at 0 and 6 months. Use of the multi-sensor armband, self-monitoring of energy intake, and self-monitoring of weight were computed for the 6 month intervention period. RESULTS: For TECH, there were significant correlations between weight loss and both self-monitoring of weight (r=0.77, p=0.01) and self-monitoring of energy intake (r=0.63, p=0.01), with no association between weight loss and time wearing the armband. Regression analysis revealed that only frequency of self-monitoring of body weight was predictive of weight loss, which explained 56% of the variability in weight loss (p=0.002). None of the self-monitoring variables using technology were significantly associated with weight change in SBWL+TECH. CONCLUSION: These findings provide insight into the importance of regular self-monitoring of body weight within interventions delivered remotely using technology that do not include an in-person intervention component. These results require replication using a larger sample followed over a longer period of time, and do not downplay the importance of self-monitoring of physical activity and energy intake within weight loss interventions.