Cluster analysis of changes in physique among Japanese children and adolescents during 1900-2015

Abstract

Objective To analyze changes in physique change among children and adolescents in Japan from 1900 to 2015, and to provide the scientific basis for national constitution development strategy in China.

Methods Data on height and weight of Japanese children and adolescents aged 6–17 years provided by the Ministry of Foreign Affairs. Cluster analysis was performed to analyze the data.

Results The 5 time periods of highest physique growth rate of Japanese boy and girls were 1948–1950, 1950–1955, 1955–1960, 1960–1965, 1965–1970, and the 5 time periods of lowest growth rate were 1939–1948, 2005–2010, 2000–2005, 1900–1905, 2010–2015, 1995–2000. Physique growth of Japanese children and adolescents showed a relatively constant increasing trend before World War II and the late 20th century, and a rapid increasing trend during 20 years after World War II and a decreasing trend during and short period after World War II. In the cluster analysis, the lower half of male students fell into a single time period (1939–1948) showing the highest rate of decline.

Conclusion Physical changes of Japanese children and adolescents are closely related to the socio–economic environment, and rapid increasing trend is observed during 20 years after World War II. Based on experiences from Japan, rapid socio–economic growth in China provides an important opportunity to promote physical development of children and adolescents. Cautions should be paid to the risk of overweight and obesity accompanied by economic growth.

Abstract

【摘要】目的分析日本儿童青少年体格在 1900—2015 年间的变化趋势, 为中国儿童青少年体格发展提供科学借 鉴。 方法 采用日本总务省提供的 1900—2015 年（ 1921, 1940—1947 年除外） 6〜17 岁日本儿童青少年身高、体重数据, 运 用聚类分析法等方法对数据进行分析归类, 每 5 年视为一个观察“单位”。 结果 日本男女生体格增长率居前 5 位的“单 位”为 1948—1950, 1950—1955, 1955—1960, 1960—1965, 1965—1970 年, 居后 5 位的“单位”为 1939—1948, 2005—2010, 2000—2005, 1900—1905, 2010—2015 年；日本儿童青少年体格在“二战”前和 20 世纪后期呈现较为匀速的增长趋势, 在 “二战”后的 20 年呈快速增长趋势, 在“二战”期间及战后初期呈负增长趋势;聚类分析中, 男生下半区为单一“单位”的为 1939—1948 年, 特点为体格最高的负增长率。 结论 日本儿童青少年体格变化与社会经济环境密切相关, 体格变化峰值 处在“二战”后的 20 年左右区间内。参照日本经验, 中国社会经济的快速增长为促进儿童青少年体格发展提供了重要契 机, 但也应重视同时伴随发生的超重和肥胖率。