The purpose of this study was to determine the effects of smartphone apps applying BodyThink program on BMI, percentage of body fat, skeletal muscle rate, body image, and self-esteem of adolescent girls.

Sixty-eight high school girls with a BMI of over 25kg/m² were recruited to participate in this study. Girls from four schools were divided into two groups: the experimental group, which used the smartphone apps applying BodyThink program, and the control group, which used smartphone apps and small group counseling. The experimental group received the BodyThink program 6 times, scheduled once a week, with each session lasting 40~50 minutes. Test measures were completed before and after the 6 week intervention period for all participants. Collected data was analyzed using Shapiro-Wilk test, descriptive statistics, χ² test, independent t-test, Mann-Whitney U test with the SPSS/WIN 18.0 program.

The girls in the experimental group significantly improved their results in BMI(Z=-1.67, p=.042), percentage of body fat (Z=-3.01, p=.001), skeletal muscle rate (t=-3.50, p<.001), and self-esteem (t=2.66, p=.005) after the program, compared to the girls in the control group.

Mobile applications applying psychological and emotional intervention programs have the potential to be effective alternative methods to improve the body composition and self-esteem of obese adolescent girls.