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. 2016 Nov;99(5):443-453.
doi: 10.1007/s00223-016-0174-y. Epub 2016 Jul 12.

Influence of a School-based Physical Activity Intervention on Cortical Bone Mass Distribution: A 7-year Intervention Study

Jesper Fritz  1 , Rachel L Duckham  2 , Timo Rantalainen  2 , Björn E Rosengren  3 , Magnus K Karlsson  3 , Robin M Daly  2
Affiliations

Influence of a School-based Physical Activity Intervention on Cortical Bone Mass Distribution: A 7-year Intervention Study

Jesper Fritz et al. Calcif Tissue Int. 2016 Nov.

Abstract

Cortical bone mass and density varies across a bones length and cross section, and may be influenced by physical activity. This study evaluated the long-term effects of a pediatric school-based physical activity intervention on tibial cortical bone mass distribution. A total of 170 children (72 girls and 98 boys) from one school were provided with 200 min of physical education per week. Three other schools (44 girls and 47 boys) continued with the standard 60 min per week. Tibial total and cortical area, cortical density, polar stress-strain index (SSI), and the mass and density distribution around the center of mass (polar distribution, mg) and through the bones cortex (radial distribution subdivided into endo-, mid-, and pericortical volumetric BMD: mg/cm3) at three sites (14, 38, and 66 %) were assessed using peripheral quantitative computed tomography after 7 years. Girls in the intervention group had 2.5 % greater cortical thickness and 6.9 % greater SSI at the 66 % tibia, which was accompanied by significantly greater pericortical volumetric BMD compared to controls (all P < 0.05). Region-specific differences in cortical mass were also detected in the anterior, medial, and lateral sectors at the 38 and 66 % tibial sites. There were no group differences at the 14 % tibia site in girls, and no group differences in any of the bone parameters in boys. Additional school-based physical education over seven years was associated with greater tibial structure, strength, and region-specific adaptations in cortical bone mass and density distribution in girls, but not in boys.

Keywords: Bone distribution; Children; Physical activity; pQCT.

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Conflict of interest statement

Compliance with Ethical StandardsConflict of InterestJesper Fritz, Rachel L Duckham, Timo Rantalainen, Björn E. Rosengren, Magnus K Karlsson, and Robin M Daly declare that they have no conflict of interest to disclose. The authors have full control of all primary data and agree to allow the journal to review the data if requested.Human and Animal Rights and Informed Consent StatementsInformed consent was obtained from all parents and participating children prior to the commencement of the study. The study was approved by the ethics committee of Lund University, conducted according to the Declaration of Helsinki and was registered as a clinical trial (ClinicalTrials.gov.NCT00633828).

Figures

Fig. 1
Fig. 1
Flow chart describing number of participants included and drop outs
Fig. 2
Fig. 2
Example of the polar (a) and radial (b) distribution analysis of the left tibia
Fig. 3
Fig. 3
Mean age-adjusted cortical bone mineral mass (mg) at tibia 14, 38, and 66 % at the 7-year follow-up in the boys and girls in the intervention compared to control group; dagger represents P < 0.05 and asterisk represents P < 0.01
See this image and copyright information in PMC

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References

    1. Gunter K, Baxter-Jones AD, Mirwald RL, Almstedt H, Fuchs RK, Durski S, Snow C. Impact exercise increases BMC during growth: an 8-year longitudinal study. J Bone Miner Res. 2008;23:986–993. doi: 10.1359/jbmr.071201. - DOI - PMC - PubMed
    1. Heinonen A, Oja P, Kannus P, Sievanen H, Haapasalo H, Manttari A, Vuori I. Bone mineral density in female athletes representing sports with different loading characteristics of the skeleton. Bone. 1995;17:197–203. doi: 10.1016/8756-3282(95)00151-3. - DOI - PubMed
    1. Gunter K, Baxter-Jones AD, Mirwald RL, Almstedt H, Fuller A, Durski S, Snow C. Jump starting skeletal health: a 4-year longitudinal study assessing the effects of jumping on skeletal development in pre and circum pubertal children. Bone. 2008;42:710–718. doi: 10.1016/j.bone.2008.01.002. - DOI - PubMed
    1. Siris ES, Baim S, Nattiv A. Primary care use of FRAX: absolute fracture risk assessment in postmenopausal women and older men. Postgrad Med. 2010;122:82–90. doi: 10.3810/pgm.2010.01.2102. - DOI - PubMed
    1. Daly RM. The effect of exercise on bone mass and structural geometry during growth. Med Sport Sci. 2007;51:33–49. doi: 10.1159/000103003. - DOI - PubMed

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