Pubertal stage and measures of adiposity in British schoolchildren

Abstract

Background: Puberty is a critical period in the development of obesity. Body mass index (BMI), waist circumference and skin-fold thickness are used generally as estimates of body fat in children and adults.

Aim: To identify a marker of adiposity that is independent of pubertal status and determine its relationship to physical fitness in adolescence.

Subjects and methods: Girls (n = 147) and boys (n = 100) from year 8 in three Welsh schools self-reported Tanner stages. Anthropometric measurements of adiposity were made and aerobic fitness estimated with a 20-metre shuttle-run test.

Results: Children in early and late puberty were of similar chronological age. BMI strongly correlated with height in early puberty in girls (r = 0.366, p < 0.001) and boys (r = 0.594, p < 0.001), but not in late puberty. Waist-to-height ratio adjusted for the effect of height on waist measurements; and correlated with percentage fat mass in early and late puberty in girls (r = 0.865 and r = 0.772, both p < 0.001) and boys (r = 0.868 and r = 0.877, both p < 0.001). Physical fitness score was inversely related to waist-to-height ratio, with similar regression lines in early and late puberty, in girls (r = − 0.545, p < 0.001 and r = − 0.362, p = 0.005) and boys (r = − 0.490, p < 0.001 and r = − 0.400, p = 0.003).

Conclusion: Pubertal status should be taken into account in adjusting weight for height in adolescents. Waist-to-height ratio is a convenient and appropriate measure of adiposity during puberty.

Keywords::

• Puberty
• anthropometry
• body mass index
• waist circumference
• physical activity

Acknowledgements

We would like to thank the parents, teachers and, most importantly, the children who participated in this study. These data were presented in part at the Society for the Study of Human Biology Symposium, celebrating the Human Biology of Jim Tanner, Cambridge UK, December 2011.

Declaration of interest : The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper