Combined use of a wristband and a smartphone to reduce body weight in obese children: randomized controlled trial.

BACKGROUND: Technological instruments may help control paediatric obesity.

OBJECTIVE: We tested whether a personalized programme based on the energy expenditure obtained from a wristband (WB) and the energy intake obtained from a smartphone application (APP) is superior to a standard approach at promoting weight loss.

METHODS: We performed a randomized controlled trial in obese children aged 10-17 years. The experimental (EXP) and control (CTR) groups were given a low-energy diet and a prescription for physical activity. The EXP group was equipped with a WB and an APP and given personalized feedback every 7 days. The main outcome was weight loss at 3 months.

RESULTS: The mean (standard deviation) z-score of body mass index at the enrollment was 2.20 (0.47) in the EXP (n = 16 out of 23) and 2.09 (0.34) in the CTR group (n = 14 out of 20) of children who completed the trial. The mean (95%CI) difference in weight loss at 3 months was 0.07 kg (95%CI: 2.81 to 2.96) for EXP vs. the CTR.

CONCLUSION: A personalized lifestyle programme based on a WB and an APP was not superior to a standard lifestyle programme at promoting weight loss in obese children.