@inproceedings{RietschScheffler2011,
  author    = {Rietsch, Katrin and Scheffler, Christiane},
  title     = {Association between skeletal robustness and physical activity in schoolchildren - First results},
  series = {Journal of biological and clinical anthropology : Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft f{\"u}r Anthropologie},
  volume    = {68},
  booktitle = {Journal of biological and clinical anthropology : Anthropologischer Anzeiger ; Mitteilungsorgan der Gesellschaft f{\"u}r Anthropologie},
  number    = {4},
  publisher = {Schweizerbart},
  address   = {Stuttgart},
  issn      = {0003-5548},
  pages     = {516 -- 516},
  year      = {2011},
  language  = {en}
}
@article{RietschEccardScheffler2013,
  author    = {Rietsch, Katrin and Eccard, Jana and Scheffler, Christiane},
  title     = {Decreased external skeletal robustness due to reduced physical activity?},
  series = {American journal of human biology : the official journal of the Human Biology Council},
  volume    = {25},
  journal   = {American journal of human biology : the official journal of the Human Biology Council},
  number    = {3},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {1042-0533},
  doi       = {10.1002/ajhb.22389},
  pages     = {404 -- 410},
  year      = {2013},
  abstract  = {Objectives Childhood obesity is a global problem, e.g., due to physical inactivity. External skeletal robustness (Frame-Index) has decreased in German schoolchildren. An association between Frame-Index and physical activity was assumed. Further often body mass index (BMI) is analyzed without reference to bone structure. Therefore, we analyze relationships between Frame-Index, BMI, \% body fat, and physical activity. Methods In a cross-sectional study, 691 German children aged 610 years were investigated. BMI, \% body fat, Frame-Index, total steps p.w., sports club rate p.w., training time p.d., and TV-time p.d. were determined. Results Total steps (P<0.001), BMI (P<0.001), and \% body fat (P=0.024) are positively linked to Frame-Index. Total steps (P<0.001), sports club rate (P=0.001), and training time (P<0.001) are negatively associated with \% body fat. Total steps (P=0.017) are negatively linked to BMI. TV-time is positively related to BMI (P<0.001) and \% body fat (P<0.001). \% Body fat is affected by age (P<0.001), sex (P=0.028), and total steps (P=0.002). BMI is influenced by age (P<0.001), and Frame-Index by sex (P<0.001) and total steps (P=0.029). Principal component analysis indicates an association between BMI and TV-time and Frame-Index and total steps. Conclusions We demonstrate an association between external skeletal robustness and physical activity, which is not captured by in BMI measurements. Children should be physically active in order to maintain skeletal robustness. Am. J. Hum. Biol. 25:404410, 2013.},
  language  = {en}
}
@article{RietschGodinaScheffler2013,
  author    = {Rietsch, Katrin and Godina, Elena and Scheffler, Christiane},
  title     = {Decreased External Skeletal Robustness in Schoolchildren - a Global Trend? ; Ten Year Comparison of Russian and German Data},
  series = {PLoS one},
  volume    = {8},
  journal   = {PLoS one},
  number    = {7},
  publisher = {PLoS},
  address   = {San Fransisco},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0068195},
  pages     = {7},
  year      = {2013},
  abstract  = {Objectives: Obesity and a reduced physical activity are global developments. Physical activity affects the external skeletal robustness which decreased in German children. It was assumed that the negative trend of decreased external skeletal robustness can be found in other countries. Therefore anthropometric data of Russian and German children from the years 2000 and 2010 were compared. Methods: Russian (2000/2010 n = 1023/268) and German (2000/2010 n = 2103/1750) children aged 6-10 years were investigated. Height, BMI and external skeletal robustness (Frame-Index) were examined and compared for the years and the countries. Statistical analysis was performed by Mann-Whitney-Test. Results: Comparison 2010 and 2000: In Russian children BMI was significantly higher; boys were significantly taller and exhibited a decreased Frame-Index (p = .002) in 2010. German boys showed significantly higher BMI in 2010. In both sexes Frame-Index (p = .001) was reduced in 2010. Comparison Russian and German children in 2000: BMI, height and Frame-Index were different between Russian and German children. German children were significantly taller but exhibited a lower Frame-Index (p<.001). Even German girls showed a significantly higher BMI. Comparison Russian and German children in 2010: BMI and Frame-Index were different. Russian children displayed a higher Frame-Index (p<.001) compared with Germans. Conclusions: In Russian children BMI has increased in recent years. Frame-Index is still higher in Russian children compared with Germans however in Russian boys Frame-Index is reduced. This trend and the physical activity should be observed in the future.},
  language  = {en}
}
@article{RietschEccardScheffler2013,
  author    = {Rietsch, Katrin and Eccard, Jana and Scheffler, Christiane},
  title     = {Decreased external skeletal robustness due to reduced physical activity?},
  year      = {2013},
  language  = {en}
}
@article{RietschGodinaScheffler2013,
  author    = {Rietsch, Katrin and Godina, Elena and Scheffler, Christiane},
  title     = {Decreased external skeletal robustness in schoolchildren : a global trend? Ten year comparison of Russian and German data},
  year      = {2013},
  language  = {en}
}
@phdthesis{Rietsch2013,
  author    = {Rietsch, Katrin},
  title     = {Body composition especially external skeletal robustness in association with physical activity and recreation in pre-pubertal children : a national and international investigation},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-66913},
  school      = {Universit{\"a}t Potsdam},
  year      = {2013},
  abstract  = {In children the way of life, nutrition and recreation changed in recent years and as a consequence body composition shifted as well. It is established that overweight belongs to a global problem. In addition, German children exhibit a less robust skeleton than ten years ago. These developments may elevate the risk of cardiovascular diseases and skeletal modifications. Heredity and environmental factors as nutrition, socioeconomic status, physical activity and inactivity influence fat accumulation and the skeletal system. Based on these negative developments associations between type of body shape, skeletal measures and physical activity; relations between external skeletal robustness, physical activity and inactivity, BMI and body fat and also the progress of body composition especially external skeletal robustness in comparison in Russian and German children were investigated. In a cross-sectional study 691 German boys and girls aged 6 to 10 years were examined. Anthropometric measurements were taken and questionnaires about physical activity and inactivity were answered by parents. Additionally, pedometers were worn to determinate the physical activity in children. To compare the body composition in Russian and German children data from the years 2000 and 2010 were used. The study has shown that pyknomorphic individuals exhibit the highest external skeletal robustness and leptomorphic ones the lowest. Leptomorphic children may have a higher risk for bone diseases in adulthood. Pyknomorphic boys are more physically active by tendency. This is assessed as positive because pyknomorphic types display the highest BMI and body fat. Results showed that physical activity may reduce BMI and body fat. In contrast physical inactivity may lead to an increase of BMI and body fat and may rise with increasing age. Physical activity encourages additionally a robust skeleton. Furthermore external skeletal robustness is associated with BMI in order that BMI as a measure of overweight should be consider critically. The international 10-year comparison has shown an increase of BMI in Russian children and German boys. Currently, Russian children exhibit a higher external skeletal robustness than the Germans. However, in Russian boys skeleton is less robust than ten years ago. This trend should be observed in the future as well in other countries. All in all, several measures should be used to describe health situation in children and adults. Furthermore, in children it is essential to support physical activity in order to reduce the risk of obesity and to maintain a robust skeleton. In this way diseases are able to prevent in adulthood.},
  language  = {en}
}