Engaging self-correcting feedback control to increase physical activity and reduce body weight and disease risk in overweight sedentary adults

Introduction: Physical activity recommendations and interventions for weight loss and disease prevention in overweight adults suffer from low compliance and high drop-out rates. We hypothesized that engaging web-enabled cognitive feedback control over the introduction of individually prescribed leisure time physical activity (LTPA) will yield adoption of health enhancing LTPA volumes among sedentary, overweight adults, and promote clinically relevant improvements of anthropometric, metabolic and fitness-related vital signs. Materials and Methods: Longitudinal LTPA intervention study, commencing with a minimum weekly requirement of 3×20 minutes of individually designed high-intensity interval training (HIT), and requirement for web-based self-monitoring and -reporting of LTPA volume and body weight. Subjects: 83 overweight, sedentary, otherwise healthy adults (age 26–68y, BMI 25.1-. 41.7kg/m², 24% female). Measurements: Anthropometric parameters, body fat (phase sensitive multi-frequency BIA), total-to-HDL cholesterol ratio, VO2peak (cardiopulmonary exercise testing, CPET), self-reported time spent for LTPA, frequency and latency of use of the web-enabled tool. Results: At 24-week follow-up, substantial voluntary increase of time spent for LTPA (mean and median of 135 and 170 minutes per week respectively) in the group of 72% of participants who successfully engaged cognitive feedback control (CFG), vs. no increase in the remaining participants who served as the control group (CG). CFG witnessed significantly improved peak oxygen consumption >1 metabolic equivalent (MET) vs. no improvement in CG. CFG also reduced BMI, body weight, body fat and TCH/HDL by 1.6kg/m², 4.8kg, 3.6kg and 0.25 respectively in CFG vs. 0.4kg/m², 1.4kg, 1.1kg and an increase in TCH/HDL ratio (0.16) in CG. Discussion: Engaging self-correcting feedback via internet-based self-monitoring and feedback control may be a promising strategy for instituting sustainable health enhancing behavior change in overweight adults, offering the possibility of open-ended intervention delivery at low costs.