Body composition is a basic feature of the machinery of the human body. Knowledge on body composition provides valuable information for apart of clinical and research settings. Several studies have suggested relations between one of the accepted methods of determining body fat and a simpler technique, which could be widely applied. The present is aimed to describe the body composition of Pre-adolescents (9-12 years) by age, gender and to compare the agreement of BSA (Body Stat 1500 Analyzer) with the derived from Skin fold Thickness.

A total number of 450 children were selected and grouped in 3 age groups i.e., 9-10 years age group, 10-11 years age group and 11-12 years age group. Each age group consists of 75 girls and 75 boys. The subjects were recruited from schools of Hyderabad and Secunderabad. Skinfold thickness was measured to the nearest 0.05 mm on the left side of the body from sites i.e., triceps, biceps, sub scapular and suprailliac by using Harpenden’s caliper. The percent body fat was calculated by using the formula: Fat (%) = [(4.95/density) – 4.5] +100(1). Later body composition was analyzed using BSA unit which works on the principle of Bioelectrical Impedance Analysis (BIA) and the parameters included are fat (% and kg), Fat free mass (% and kg) and water (% and liters).

Sex related differences in body composition were observed in boys and girls. The mean fat (% and kg) was significantly (p>0.005) higher in girls (42.2% and 12.3 kg) than boys (35.2% and 9.8 kg) where as the mean fat free mass was higher significantly (p >0.005) in boys (64.7% and 20.1 kg) than girls (53.6% and 18 kg)(2). The mean water levels (% and liters) were also higher in boys (74.2% and 22.9 liters) than girls (68.4% and 20.3 liters).

The correlation results also showed that skin fold thickness strongly correlated with body weight (0.01%) (r.0.208) and a negative correlation (0.01%) (r.0.208) was observed between BSA fat mass (%), water (% and liters) and body weight. There was a positive correlation between weight and fat free mass (0.01%) (r.0.208) and negative correlation between fat mass and lean mass. It was also calculated that there was a significant difference at 5% level in the fat free mass (%) between the subjects who have maximum weight than minimum weight subject and significant difference was observed in both genders.

The total body fat and percent body fat decreased with increase in age in both genders. The average decrease in total body fat for girls was 13.2 kg at 9-10 years and 11.4 kg at 11-12 years. The corresponding decrease in total body fat for boys was from 10.2 kg at 9-10 years and 9.1 kg at 11-12 years. Similarly, the average percent body fat decreased from 52.4% to 36.5% in girls and 41.9% to 26.4% in boys. The overall increase in fat free mass from 9-12 years was found both in boys and girls. The average amount of fat free mass increased about 14.4 kg in boys and 7.6 kg in girls(3).

The mean BSA fat mass (% and kg) decreased with increase in age (41.9 to 26.4, boys and 52.4 to 36.5, girls) whereas SFT fat (% and kg) increased with an increase in age from 9-12 years (17.6 to 22.7, boys and 21.5 to 29.4, girls). BSA and SFT fat free mass (% and kg) increased with an age in boys and girls. BSA fat mass (%) was significantly higher (p <0.01) than SFT fat (%) except at the age of 11-12 years in boys where as significant difference (p <0.05) was observed between BSA fat (kg) and SFT (kg) except at the age of 9-10 years in girls. SFT fat free mass (% and kg) was higher than BSA fat free mass (% and kg) in boys and girls of all age groups.

Hence, assessment of body composition by BSA was not in agreement with that of SFT at the age of 9-10 years indicating that the BSA does not read the body composition of young children. But at the age of 11-12 years the agreement between BSA and SFT increased indicating BSA was suitable to assess body composition from 11 years onwards.

K. Rajeswari,
V. Vijaya Lakshmi,
Department of Foods & Nutrition,
College of Home Science,
Acharya N.G. Ranga Agricultural University, Hyderabad,
Andhra Pradesh, India.
E-mail: [email protected]

1. Siri WE. Body Composition from fluid spaces and density: analysis of methods. In techniques for Measuring Body Composition. 1966; pp. 223-244, Washington, DC National Academy of Sciences.

2. Guo SS, Chumela WC, Roche AF, Sievogel RM. Age and maturity related changes in body composition during adolescence into adulthood. The fels longitudinal study. Int J Obesity Related Metab Disord 1997; 52: 1147-1175.