Association between BMI and health-related physical fitness: A cross-sectional study in Chinese high school students

Abstract

BackgroundExisting studies reporting on the levels of physical fitness among high school students use relatively few fitness tests for indicators of physical fitness, thus, incomprehensively evaluating the levels of physical fitness. Therefore, this study investigated the relationship between body mass index (BMI) and physical fitness index (PFI) by investigating five physical fitness indicators and calculating PHI.MethodAnthropometric measurements and indicators from five measures of physical fitness (50-m sprint, sit and reach, standing long jump, 800/1,000-m run, pull-up/bent-leg sit-up) were assessed. BMI was calculated to classify individuals into underweight, normal weight, overweight, and obese categories. Z-scores based on sex-specific mean and standard deviation were calculated, and the sum of Z-scores from the six fitness tests indicated the PFI. The findings were fitted to a linear regression model to elucidate the potential relationship between BMI and PFI.ResultsIn total, 176,655 high school students (male: 88,243, female: 88,412, age: 17.1 ± 1.05 years, height: 168.87 ± 11.1 cm, weight: 62.54 ± 15.15 kg) in Jinan, China, completed the physical fitness tests between 2020 and 2021. The one-way ANOVA models showed that PFI in the normal category was significantly higher as compared to all the other BMI categories within both male and female groups (p < 0.001), and PFI in the obese category was significantly lower as compared to all the other BMI categories for both male and female groups (p < 0.001). The association between PFI and BMI showed an inverted U-shape relationship.ConclusionsThis study demonstrated that BMI affects the PFI in both males and females. As compared to the obese and overweight categories based on BMI, significantly higher scores of PFI were observed for males and females.

The relationships between body mass index, reciprocal ponderal index, waist-to-height ratio, and fitness in young adult males

“…The best predictor for COD also appears to be BMI. Thus, our results are consistent with those of previous studies ( Campa et al, 2019 ; Chen et al, 2020 ; Qin et al, 2022 ). However, discrepancies remain between studies, as some have identified the RPI as the best predictor of COD ( Silva et al, 2016 ).…”

“…BMI has been widely used to quantify body fat and identify people who are overweight ( Qin et al, 2022 ) which have negative consequences for the health of children (e.g., dyslipidemia, arterial stiffness, and less cardio-respiratory capacity) ( Vaara et al, 2013 ; Abdelkarim et al, 2020 ) and adults (e.g., risk of heart attack) ( Jafari et al, 2019 ). Several studies have identified that a high BMI is related to poor cardiorespiratory fitness and vertical jump ( Qin et al, 2022 ; Manzano-Carrasco et al, 2023 ), which is linked to effects by the kind of sport done on physical fitness ( Tahira, 2021 ). In this sense, regular sport participation could be a great strategy to increase fitness and combat the consequences of high BMI ( Tahira, 2021 ).…”

Relationship between Body Mass Index and lower limb strength in children and adolescents

“…These ndings are consistent with other studies conducted in various geographic regions of the world, which have shown quadratic (non-linear) relationships, clearly re ecting that schoolchildren categorized as underweight and overweight according to BMI induce negative effects on physical tness levels in children and adolescents [17,19,20,24] On the contrary, in the normal BMI category, the best results in HJ were observed in schoolchildren of both sexes.…”

Secular trends in physical fitness of rural Chinese children and adolescents aged 7–18 years from 1985 to 2019

“…During the period 2000-2019, the BMI of boys and girls in all age groups increased and the increase accelerated, especially in those aged 16-18 years. It has been shown that both higher and lower BMI can have a detrimental effect on physical fitness 22,59 . Overweight and obesity individuals tend to perform less physical activity, have longer screen time, consume more calories 60 and have a substantial decrease in physical activity.…”