title: Intergenerational changes in chest size and proportions in children and adolescents aged 3-18 from Kraków (Poland), within the last 70 years.
abstract: OBJECTIVE
  The size and proportions of the human body change continuously in response to social change and economic development. As reported by papers on intergenerational changes in chest size, this part of the human body is also influenced by environmental factors. The aim of this study was to assess changes in the dimensions and proportions of the chest of children and adolescents over a span of 70 years.
  
  
  METHODS
  In 2010 an anthropological study was conducted on 3878 children and adolescents aged 3-18 years living in Kraków (Poland). Data on chest dimensions (breadth, depth, circumference, chest index) were compared to data from 1938 (3719 children) and 1983 (6464 children).
  
  
  RESULTS
  In boys, chests became increasingly deep; in boys 18 years of age, the chest index increased by 4.8 units, unlike girls, whose chests markedly flattened. The chest index in girls 18 years of age decreased by 4.2 units. In almost all age categories these differences were statistically significant. Also, in all age categories, children studied in 2010 had a significantly bigger chest circumference than boys and girls surveyed in 1983, respectively, by averages of 3.6 cm and 3 cm.
  
  
  CONCLUSIONS
  The main reason for these changes may be the socio-economic transformation, which has been especially strong in recent decades. These results may have practical importance in many areas of knowledge, including medicine, nutritional science, and sports. They can also be important for informing preventive measures that should be taken in order to increase the physical activity of children and youth, especially boys.
authors.affiliation: Department of Anthropology, University of Physical Education, Faculty of Physical Education, Kraków, Poland.
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Kryst
authors.affiliation: Department of Anthropology, University of Physical Education, Faculty of Physical Education, Kraków, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Woronkowicz
authors.affiliation: Department of Anthropology, University of Physical Education, Faculty of Physical Education, Kraków, Poland.
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Kowal
authors.affiliation: Department of Anthropology, University of Physical Education, Faculty of Physical Education, Kraków, Poland.
authors.forename: Jan
authors.initials: J
authors.lastname: Sobiecki
mesh_terms: D000293:Adolescent; D000886:Anthropometry; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D011044:Poland; D013909:Thorax / Q000033:anatomy & histology*; D013997:Time Factors
keywords: chest breadth; chest circumference; chest depth; chest index; secular trend