Effects of walking or resistance training on weight loss maintenance in obese, middle-aged men: a randomized trial

OBJECTIVE: To investigate whether walking or resistance training improves weight maintenance after weight loss when added to dietary counselling. DESIGN: Two months' weight reduction with very-low-energy-diet (VLED) followed by randomization into three groups (control, walking, resistance training) for 6 months' weight maintenance (WM) program and 23 months' unsupervised follow-up. During VLED and WM all groups received similar dietary counselling. SUBJECTS: The main inclusion criteria were BMI > 30 kg/m(2), waist > 100 cm and physical inactivity (exercise less than or equal to once a week). Ninety healthy, obese (mean BMI 32.9 kg/m(2) and waist 112.5 cm), 35 - 50 y-old men started the study and 68 were measured at the end of the study. MEASUREMENTS: Weight and body composition assessed by underwater weighing. Exercise diaries and dietary records to assess energy balance. RESULTS: During VLED the mean body weight decreased from 106.0 (s.d. 9.9) kg to 91.7 (9.4) kg. Weight was regained mostly during follow-up and in the end of the study the mean weight in groups was 99.9 - 102.0 kg. Exercise training did not improve short or long-term weight maintenance when compared to the control group. However, resistance training attenuated the regain of body fat mass during WM (P = 0.01), but not during follow-up. In the combined groups the estimated total energy expenditure (EE) of reported physical activity was associated with less weight regain during WM. EE of 10.1 MJ/week was associated with maintaining weight after weight loss. EE of physical activity tended to decrease after WM in exercise groups due to poor long-term adherence to prescribed exercise. Energy intake seemed to increase during follow-up. CONCLUSION: Exercise training of moderate dose did not seem to improve long-term weight maintenance because of poor adherence to prescribed exercise.