Association between body mass index and physical fitness index in Chinese and Japanese children and adolescents

Abstract

Objective To determine the relationship between body mass index (BMI) and physical fitness index (PFI) in Chinese and Japanese children and adolescents and to provide theoretical support for physical fitness improvement in Chinese children and adolescents.

Methods A total of 9 594 children and adolescents aged 7–18 years were tested in China and Japan, 4 800 of which with various BMI were randomly selected for analyzing and comparing PFI between the two countries. The relationship between different BMI–Z scores and PFI was analyzed.

Results In general, the PFI of wasting, normal weight, overweight and obesity in Chinese boys was –1.17, –0.03, 0.04 and 0.26, the figures were –2.59, –0.34, –1.46 and –2.44 for Japanese boys, significant differences were found in overweight and obese group ( P<0.01). the PFI of wasting, normal weight, overweight and obesity in Chinese girls was –1.18, –0.08, 0.01 and 1.03, the figures were –1.21, 0.51, 0.11 and –1.30 for Japanese girls, significant differences were found in normal weight and obese group (P<0.05). Significant differences in PFI were found within Chinese boys, Chinese children, Japanese boys, Japanese girls and Japanese children with different BMI— Z levels ( F = 2.89, 3.05, 4.81, 2.33, 5.34, P<0.01).

Conclusion There is an inverted ”U” curve relationship between BMI and PFI in Chinese and Japanese children and adolescents. With the increase of BMI–Z score, decreasing rate of PFI in Chinese boys is higher than Japanese boys. Practical and effective intervention measures should be taken to improve physical fitness of children and adolescents in China.

Abstract

【摘要】目的了解中日两国儿童青少年体质量指数 （BMI) 与体能指数 （PFI) 之间的关系, 为有效提髙中国儿童青 少年体能水平提供支持和依据。 方法 在中国和日本共测试9 594名7~ 18岁儿童青少年体能项目, 采用随机个案法抽取 其中4 800名作为研究对象, 比较中日两国不同肥胖程度儿童青少年体能指数存在的差异, 并分析不同 BMI–Z 分与 PFI 之 间的关系。 结果 中国男生消瘦、正常、超重和肥胖分组的 PFI 均值分别为 –1. 17, –0.03, 0.04 和 0.26, 日本男生分别为– 2. 59, –0. 34, –1. 46和–2. 44, 超重和肥胖学生差异均有统计学意义 （ P值均 <0. 01)；中国不同 BMI 分组女生的 PFI 均值分 别为 –1. 18, –0. 08, 0. 01 和 1.03, 日本女生分别为 –1.21, 0.51, 0. 11 和–1.30, 中国正常 BMI 女生 PFI 低于日本, 肥胖女生 则髙于日本 （ P值均<0.05)。中国男生、总体和日本男生、女生、总体方面不同 BMI–Z 值的 PFI 差异均有统计学意义 （ F值 分别为 2. 89, 3. 05, 4. 81, 2. 33, 5. 34, P值均<0. 01)。 结论 中日儿童青少年 BMI–Z 分与 PFI 之间存在倒“U”型曲线关系, 随着 BMI–Z 分升髙中国男生 PFI 的下降幅度较日本男生更为显著。应结合中国实际采取有效的干预措施, 提髙儿童青少 年体能水平。