877 digital scales

All children undertook anthropometric assessments at the school sites according to standard procedures [30 ]. Height and sitting height were measured to the nearest 0.1 cm using a portable stadiometer (Seca 213 height measure, Seca UK, Birmingham, UK). Body mass was measured to the nearest 0.1 kg using calibrated digital scales (Seca 877 digital scales, Seca UK, Birmingham, UK). Body mass index (BMI) was calculated from height and body mass as a proxy measure of body composition (kg · m²), and BMI z-scores were assigned to each child [31 (link)]. Age and sex-specific BMI cutpoints were used to classify children’s weight status [32 (link)]. Gender-specific regression equations [33 (link)] were used to predict children’s maturity offset (i.e., age from peak height velocity), which was used as a proxy measure of somatic maturation.

Height was measured to the nearest 0.1 cm using a portable stadiometer (Seca 213 height measure, Seca UK, Birmingham, UK). Body mass was measured to the nearest 0.1 kg using digital scales (Seca 877 digital scales, Seca UK, Birmingham, UK). Waist circumference was measured to the nearest 0.1 cm using a non-elastic measuring tape, which was positioned around the mid-section of the waist, over the participants’ school shirts. All anthropometric measures were administered and recorded by pairs of trained researchers in accordance with standardised procedures [28 ]. Height and weight data were converted to body mass index (BMI), which were subsequently used to categorise participants into weight status classifications using International Obesity Task Force BMI cut-points (11).