In the intervention group, the researcher gave feedback on the subjects' exercise amount through telephone contact every 2 weeks during the 12-week study period. Through phone consultations, they answered questions about exercise or discussed problems, encouraged to continue exercising, answered questions or discussed problems related to wearable devices and apps, and encouraged continuous data transmission.

In the case of the control group, physical activity is monitored by itself through wearable devices and smartphone apps without phone counseling.

Receving regular feedback from a health provider

Blood samples were collected from the Jeonju vein after fasting for 6 hours and analyzed in our hospital's laboratory. The lipid profile was tested using an automated analyzer (Hitachi 747, Hitachi Corp, Japan) and enzyme colorimetric method. FPG levels were evaluated using glucose oxidase methods and Synchron LX 20 (Beckman Coulter, Fullerton, CA)

Blood pressure was measured in a sitting position after resting using BP-203 RVII(Colin Corp, Aichi, Japan)

The waist circumference was evaluated by a trained examiner (after normal exhalation) to the nearest millimeter from the midpoint between the lower edge of the rib and the iliac ridge.

Investigators provided with wrist-wearable device (B.BAND, B Life Inc, Korea), which allowed them to wear and live for 12 weeks. Subsequently, a compatible app was installed on the participants' mobile phones and connected to a wearable device. Researchers who have been granted access can check and track participants' steps, calorie consumption, and MVPA (moderate- to vigorousintensity physical activity) on a daily basis through a web page.

Body weight in kilograms and height in meters were measured using a digital scale and stadiometer (BSM370, Biospace Co Ltd, Seoul), while the study subjects were dressed in light clothing without shoes. Body composition was measured by bioelectrical impedance analysis (Inbody 720, Biospace Co Ltd, Seoul)

All participants received information on demographics, occupation (usually for estimating physical activity intensity), frequency and duration of physical activity, history (diagnosis or drug treatment of hypertension, diabetes or dyslipidemia), health-related habits (smoking, drinking and alcohol), and medications taken through the survey. Participants were defined as non-smokers, past smokers, and current smokers, and non-smokers (0 to 98 g/week) or drinkers who drink an average of 7 cups of men and 5 or more cups of women twice per person.