title: Comparison of Site-Specific Bone Mineral Densities between Endurance Runners and Sprinters in Adolescent Women.
abstract: We aimed to compare site-specific bone mineral densities (BMDs) between adolescent endurance runners and sprinters and examine the relationship of fat-free mass (FFM) and nutrient intake on BMD. In this cross-sectional study, 37 adolescent female endurance runners and sprinters (16.1 ± 0.8 years) were recruited. BMD and FFM were assessed by dual-energy X-ray absorptiometry. Nutrient intake and menstrual state were evaluated by questionnaires. After adjusting for covariates, spine and total bone less head (TBLH) BMDs were significantly higher in sprinters than endurance runners (TBLH, 1.02 ± 0.05 vs. 0.98 ± 0.06 g/cm²; spine, 0.99 ± 0.06 vs. 0.94 ± 0.06 g/cm²;p< 0.05). There was no significant difference between groups in other sites. The rate of menstrual abnormality was higher in endurance runners compared with sprinters (56.3% vs. 23.8%;p< 0.05). FFM was a significant covariate for BMD on all sites except the spine (p< 0.05). Dietary intake of vitamin D was identified as a significant covariate only for pelvic BMD (p< 0.05). The BMDs of different sites among endurance runners and sprinters were strongly related to FFM. However, the association of FFM with spine BMD cannot be explained by FFM alone. Other factors, including nutrition and/or mechanical loading, may affect the spine BMD.
authors.affiliation: Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu 525-8577, Japan. gr0167si@ed.ritsumei.ac.jp.
authors.forename: Aoi
authors.initials: A
authors.lastname: Ikedo
authors.affiliation: Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu 525-8577, Japan. gr0167kx@ed.ritsumei.ac.jp.|Department of Sports Science, Japan Institute of Sports Science, Nishigaoka, Kitaku, Tokyo 115-0056, Japan. gr0167kx@ed.ritsumei.ac.jp.
authors.forename: Aya
authors.initials: A
authors.lastname: Ishibashi
authors.affiliation: Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu 525-8577, Japan. saori.m0824@gmail.com.|Department of Food Science and Nutrition, Mukogawa Women's University, Nishinomiya 663-8558, Japan. saori.m0824@gmail.com.
authors.forename: Saori
authors.initials: S
authors.lastname: Matsumiya
authors.affiliation: Research Organization of Science and Technology, Ritsumeikan University, Kusatsu 525-8577, Japan. kaizaki@fc.ritsumei.ac.jp.
authors.forename: Aya
authors.initials: A
authors.lastname: Kaizaki
authors.affiliation: Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu 525-8577, Japan. ab@fc.ritsumei.ac.jp.
authors.forename: Kumiko
authors.initials: K
authors.lastname: Ebi
authors.affiliation: Graduate School of Sport and Health Science, Ritsumeikan University, Kusatsu 525-8577, Japan. safujita@fc.ritsumei.ac.jp.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Fujita
mesh_terms: D000293:Adolescent; D056352:Athletes; D015519:Bone Density / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D012420:Running; D013177:Sports / Q000502:physiology
keywords: adolescent; bone mineral density; endurance runners; fat-free mass; nutrition; sprinters