Table 1. Characteristics of the study participants at baseline and after six months.

n = 12; *: p < 0.001. Data were analyzed using paired-sample t-test; ^a: Body mass index (BMI) was calculated using the participants’ height (cm) and weight (kg); ^b: BMIz was calculated using the average and standard deviation of the BMI stratified by age, according to the guidelines of the Japanese Society for Pediatric Endocrinology; ^c: Obesity rate (%): ((measured weight – standard weight)/standard weight) × 100. The degree of obesity was categorized as mild (20-30%), moderate (30-50%), and highly obese (>50%); ​​​​​​​^d: Total body water (TBW) obtained using BIA was determined using the following equation using doubly labeled water (DLW): (y = 1.0715x + 2.125);​​​​​​​^e: Fat-free mass (FFM) derived from total body water; ​​​​​​​^f: Fat mass (FM) calculated by subtracting FFM from body weight; ​​​​​​​^g: Using Wilcoxon signed-rang sum test.

	Baseline, mean ± SD	After six months, mean ± SD	Amount of change	P-value
Age (year)	15.1 ± 1.4	15.7 ± 1.4	0.6 ± 0.5	0.002
Height (cm)	171.1 ± 3.8	171.9 ± 4.2	0.8 ± 1.2	0.049
Weight (kg)	100.1 ± 18.0	102.1 ± 19.6	2.0 ± 3.2	0.045
BMIa	34.2 ± 5.8	34.5 ± 6.3	0.3 ± 1.3	0.355
BMIzb	2.4 ± 0.6	2.4 ± 0.7	0.0± 0.1	0.638g
Obesity rate (%)c	66.9 ± 27.3	67.8 ± 29.4	0.9 ± 6.2	0.641
%Fat	33.0 ± 5.3	31.8 ± 7.5	−1.2 ± 4.1	0.001*
TBW (kg)d	49.2 ± 6.3	50.8 ± 6.0	1.6 ± 2.5	0.048
FFM (kg)e	66.3 ± 8.5	68.4 ± 7.9	2.1 ± 3.3	0.049
FM (kg)f	33.8 ± 10.2	33.7 ± 12.9	−0.1 ± 4.8	0.940