This study aimed to classify the body composition of puberty students into six categories, using Fat Mass Index (FMI) and Fat Free Mass Index (FFMI), and to identify the characteristics of their physical fitness and motor capacity in each category. FMI and FFMI are body composition (FM; Fat Mass, FFM; Fat Free Mass) divided by height squared. The participants were 1,482 high school students (815 males and 667 females) aged 15-17 years old. The body measurements were height, weight, and FFM (Fat Free Mass). In addition to the calculation of Body Mass Index, fat mass (FM) was calculated from fat free mass (FFM) and body weight, and FMI and FFMI were calculated FM, FFM and height. The students body were categorized into six groups using cluster analysis with FMI and FFMI as variables: low FFMI and low FMI (Category 1), low FFMI and normal FMI (Category 2), high FFMI and low FMI (Category 3), high FFMI and normal FMI (Category 4), high FFMI and high FMI (Category 5), and high FFMI and very high FMI (Category 6). Among the categories, Categories 3 and 4 showed significantly higher scores in total physical fitness and all the physical fitness factors, revealing endurance sports type and power sports type respectively.
