Author(s): KIDOKORO, T., KITANO, N., KLUG, M., MAGNUSSEN, C.G., TOMKINSON, G.R. , Institution: NIPPON SPORT SCIENCE UNIVERSITY, Country: JAPAN, Abstract-ID: 537

INTRODUCTION:
Although the health benefits of cardiorespiratory fitness (CRF) have been well-established, evidence for other components of PF (muscular fitness [MF] and flexibility) is lacking. Multiple PF components, including CRF, MF, and flexibility, may improve health-related predictive accuracy over single PF tests. However, no study has examined this. Given that childhood blood lipid levels track strongly into adulthood and are major risk factors for cardiometabolic disease, identifying the best predictive model using multiple PF tests in children could aid in describing current and future health. Therefore, the aim of the study was to identify the best predictive model for blood lipid levels among Japanese children using national physical PF tests (including eight PF items).
METHODS:
Participants were 983 Japanese children (489 boys and 494 girls) aged 9–12 years. PF was assessed as part of the national PF surveillance and anthropometric assessments (height and body mass). Blood lipids (triglycerides, high-density lipoprotein cholesterol [HDL-C], non-HDL-C) were directly measured or calculated from a non-fasted venous blood sample. To identify the model with the highest predictive utility for blood lipid levels, receiver operating characteristic analyses were performed to examine the area under the curve (AUC) for all combinations of the eight PF tests (1,530 models were examined).
RESULTS:
For boys, the best single predictor PF tests were the standing long jump [AUC:0.64-0.67], 20-m shuttle run [AUC:0.64-0.67], 50-m sprint [AUC:0.63-0.80], and softball throw [AUC:0.60-0.69]. These AUC values were greater than those for body mass index (BMI) [AUC:0.58-0.67], and the models remained significant even after adjusting for BMI and maturity offset. For girls, no PF test demonstrated significant discriminatory utility after adjusting for BMI and maturity offset. Using multiple PF tests (up to eight) improved the AUC; however, the changes in the AUC were negligible (<6% for boys and <4% for girls), except for HDL-C in girls.
CONCLUSION:
Our study identified the PF tests with the best utility for predicting blood lipid levels in Japanese children. For boys, the standing long jump, 20-m shuttle run, 50-m sprint, and softball throw emerged as the most superior PF tests, with their discriminatory ability superior to BMI. In contrast, no single or combination of PF test showed improved discrimination for girls after considering key covariates. Our findings suggest that multiple PF tests do not markedly improve prediction over a single PF test. Thus, using the national PF tests as an initial screening tool can identify children at risk of dyslipidaemia in Japan, potentially complementing BMI and other risk factors and aiding early education and intervention strategies.