Effects of an Exercise Intervention Based on mHealth Technology on the Physical Health of Male University Students With Overweight and Obesity: Randomized Controlled Trial

Background: Obesity has become one of today's global health challenges. According to the World Health Organization, in 2022, a total of 2.5 billion adults aged 18 years and older will be overweight, including more than 890 million adults with obesity. Objective: Exercise interventions based on mobile health (mHealth) technology are widely available, but the effectiveness and feasibility of interventions using mHealth apps and exercise watches to improve the physical health of male college students with overweight and obesity are unknown, and this study compares the effects of online interventions carried out by mHealth technology and offline interventions guided by physical trainers on the physical health of male college students with overweight and obesity. Methods: This study used a randomized controlled trial with a pretest-posttest design, and participants were randomly divided into an online group, an offline group, and a control group. The online group exercised online through the fitness app, and the offline group was instructed by a professional trainer to exercise offline, and both groups wore sports watches to monitor their activities, and the training content was the same. The control group did not carry out any intervention. Results: At the end of the intervention, the BMI of the online and offline groups decreased by 0.89(SD 1.17) and 0.68(SD 0.94)kg/m², respectively (P<.01), and the body fat rate decreased by 1.69%(SD 2.24) in the online group and 2.25% (SD 3.20)in the offline group (P<.01). Several physical fitness indicators, such as muscle mass, increased significantly by an average of 1115.23 (SD 1765.42) g in the online group and 1377.74(SD 2203.05)g in the offline group (P<.05), and lung capacity improved by 536.82 (SD 745.55) and 450.35 (SD 664.47)ml in the online and offline groups, respectively (P<.05). The changes in these indicators between the online and offline groups were not significantly different (P>.05). Additionally, a dose-effect relationship was found between the amount of physical activity and the rate of change in body fat, with a 6.9% increase in the rate of change in body fat for every 1 MET*h increase in moderate-intensity physical activity, and a 5.4% increase in the rate of change in body fat for every 1 MET*h increase in high-intensity physical activity. Conclusions: Exercise intervention based on mHealth technology effectively improves the physical fitness of male college students with overweight and obesity, and the effect is consistent with offline intervention. There was a significant dose-effect relationship between the amount of physical activity and the rate of change in body fat, which provided a scientific basis for the development of personalized training programs.