Wu Jingtao, Shao Yanhong, Hu Jun, Zhao Xinjuan
School of Physical Education, Leshan Normal University, 778 Binhe Road, Shizhong District, Leshan, Sichuan Province, 614000, China.
Xiangshui Teacher Development Center, Yancheng, China.
BMC Pediatr. 2025 Jul 1;25(1):478. doi: 10.1186/s12887-025-05647-z.
Although the nexus between Body Mass Index (BMI) and the physical fitness of the younger demographic has been well-documented, a comprehensive examination of this relationship among children from ethnic minority communities remains unexplored. This study aims to delineate the association between BMI and physical fitness among primary school students in Sichuan's ethnic minority regions, offering insights to inform health policy tailored to these communities.
Utilizing a randomized cluster sampling approach, the study was conducted across ethnic minority regions in Sichuan Province from September to October 2023, encompassing a cohort of 10,800 students from Grade 3 to Grade 6. A spectrum of physical metrics was assessed, including BMI, lung capacity, 50-m sprint, sit-and-reach, rope jumping, abdominal crunches, and shuttle run. Quantile regression analysis was applied, pinpointing 10 BMI quantiles to scrutinize the influence of physical fitness indicators across varying BMI thresholds.
The results of the study are as follows: (1) A nonlinear dynamic was identified between BMI and physical fitness indicators, with lung capacity demonstrating robust positive correlation with BMI within the intermediate range (45 th to 55 th percentiles) (β = 0.42, p < 0.001), diminishing at the extremes; (2) The 50-m sprint and standing long jump exhibited divergent correlations with BMI, with the sprint showing negative correlation at lower BMI quantiles (5 th to 25 th) and positive at higher quantiles (75 th to 95 th). Conversely, the standing long jump correlated positively within the 10 th to 30 th percentiles and negatively above the 80 th percentile; (3) Pronounced ethnic disparities were noted, particularly with Tibetan students excelling in lung capacity at elevated BMI quantiles (> 80%), showcasing a β difference of 0.15 to 0.23, p < 0.05.
(1) The correlation between Body Mass Index (BMI) and physical fitness among primary school students from ethnic minorities in Sichuan is not only nonlinear but also exhibits substantial ethnic diversity; (2) An intermediate BMI range-spanning from the 35 th to the 65 th percentiles-correlates most favorably with a broad spectrum of physical fitness indicators.
尽管体重指数（BMI）与年轻人群体身体素质之间的联系已有充分记录，但对少数民族社区儿童之间这种关系的全面研究仍未开展。本研究旨在描绘四川少数民族地区小学生BMI与身体素质之间的关联，为针对这些社区制定的健康政策提供参考依据。
本研究采用随机整群抽样方法，于2023年9月至10月在四川省少数民族地区开展，涵盖了10800名三年级至六年级的学生。评估了一系列身体指标，包括BMI、肺活量、50米短跑、坐位体前屈、跳绳、仰卧起坐和往返跑。应用分位数回归分析，确定了10个BMI分位数，以研究不同BMI阈值下身体素质指标的影响。
研究结果如下：（1）BMI与身体素质指标之间存在非线性动态关系，肺活量在中间范围（第45至55百分位数）与BMI呈强正相关（β = 0.42，p < 0.001），在两端则减弱；（2）50米短跑和立定跳远与BMI呈现不同的相关性，短跑在较低BMI分位数（第5至25百分位数）呈负相关，在较高分位数（第75至95百分位数）呈正相关。相反，立定跳远在第10至30百分位数呈正相关，在第80百分位数以上呈负相关；（3）存在明显的民族差异，特别是藏族学生在较高BMI分位数（> 80%）时肺活量表现出色，β差异为0.15至0.23，p < 0.05。
（1）四川少数民族小学生的体重指数（BMI）与身体素质之间的相关性不仅是非线性的，而且存在显著的民族多样性；（2）BMI在第35至65百分位数的中间范围与广泛的身体素质指标相关性最为有利。
