The rise of the couch potato
The decrease of external skeletal robustness of childhood continues in young adult women
DOI:
https://doi.org/10.52905/hbph2026.116Keywords:
frame index, physical activity, phenotypic plasticityAbstract
Background A decrease of external skeletal robustness in children and adolescents over the last decades has been documented. This has mainly been attributed to a lack of movement during childhood and adolescence.
Objectives This paper aims to determine whether this decrease of external skeletal robustness continues into adulthood.
Sample and methods The elbow breadth, absolute and relative pelvic breadth, Frame index and the thoracic index were analysed in 1836 women between the ages of 18 and 29 years in two cohorts (birth years 1951–1994, 1995–2005). The means, standard deviations, minima and maxima as well as selected percentiles were calculated for each of the above-named measurements of both cohorts. The results were tested for significance using a Kolmogorov-Smirnov test. The samples were collected in Germany.
Results Young women born after 1995 have lower mean values (p<0.05) for absolute pelvic breadth (27.3cm vs. 28.2cm), relative pelvic breadth (0.16 vs. 0.17), elbow breadth (5.9cm vs. 6.1cm), frame index (35.25 vs. 36.81), and thoracic index (67.87 vs. 69.46) than women born between 1951–1994.
Conclusions The trend toward a reduced external skeletal robustness observed in modern children and adolescents seems to continue into adulthood. The changes in the thoracic index appear to be due to the secular trend in growth.
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