Defining Optimal Cut-Points for Cardiorespiratory Fitness Associated With Overweight/Obesity in Children: A School-Based Study

Mario Kasović; Lovro Štefan; Vilko Petrić; Vesna Štemberger; Iva Blažević

doi:10.3389/fphys.2022.784787

Defining Optimal Cut-Points for Cardiorespiratory Fitness Associated With Overweight/Obesity in Children: A School-Based Study

Front Physiol. 2022 Mar 10:13:784787. doi: 10.3389/fphys.2022.784787. eCollection 2022.

Authors

Mario Kasović^{1

2}, Lovro Štefan^{1

2

3}, Vilko Petrić⁴, Vesna Štemberger⁵, Iva Blažević⁶

Affiliations

¹ Department of General and Applied Kinesiology, Faculty of Kinesiology, University of Zagreb, Zagreb, Croatia.
² Department of Sport Motorics and Methodology in Kinanthropology, Faculty of Sports Studies, Masaryk University, Brno, Czechia.
³ Recruitment and Examination (RECETOX), Faculty of Science, Masaryk University, Brno, Czechia.
⁴ Department of Educational Studies, Faculty of Teacher Education, University of Rijeka, Rijeka, Croatia.
⁵ Department of Primary Teacher Education, Faculty of Education, University of Ljubljana, Ljubljana, Slovenia.
⁶ Department of Primary Teacher Education, Faculty of Educational Science, University of Pula, Pula, Croatia.

Abstract

The main purpose of the study was to define optimal criterion-referenced cut-points for cardiorespiratory fitness (CRF) associated with overweight/obesity. In this cross-sectional study, participants were 1,612 children aged 7-14 years (mean age ± SD = 9.7 ± 2.4 years; 52.5% girls). CRF was assessed by the Maximal multistage 20-m shuttle run test, from which maximal oxygen uptake (VO₂max) was estimated. Anthropometric indices included body-mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR). Receiver operating characteristic (ROC) curves were performed to determine cut-off points. In boys, the optimal cut-off points of CRF in defining overweight/obesity for BMI, WC, and WHtR were 44.6, 46.4, and 46.9 mlO₂/kg/min. The areas under the curves (AUC) were 0.83 (95% CI 0.78-0.88, p < 0.001), 0.77 (95% CI 0.71-0.83, p < 0.001), and 0.90 (95% CI 0.86-0.93, p < 0.001). In girls, the optimal cut-off points were 41.0, 40.8, and 40.7 mlO₂/kg/min for BMI, WC, and WHtR, with the AUCs of 0.86 (95% CI 0.82-0.90, p < 0.001), 0.83 (95% CI 0.79-0.88), and 0.88 (95% CI 0.84-0.93, p < 0.001). In conclusion, our newly developed cut-off points for CRF assessed by the Maximal multistage 20-m shuttle run test may adequately detect primary school-aged boys and girls with general and abdominal obesity.

Keywords: anthropometric indices; diagnostics; maximal oxygen uptake; primary-school students; receiver operating curve.