Research Centre for Sport, Exercise and Performance, Faculty of Education, Health and Wellbeing, University of Wolverhampton, Walsall Campus, Gorway Rd, Walsall, WS1 3BD, UK.
Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sports, University of Porto, Porto, Portugal.
Arch Osteoporos. 2019 Apr 9;14(1):46. doi: 10.1007/s11657-019-0596-z.
Less is known on bone mass gains in dancers involved in vocational dance training. The present study found that, as young vocational dancers progress on their professional training, their bone health remains consistently lower compared to non-exercising controls. Endocrine mechanisms do not seem to explain these findings.
Little is known on bone mass development in dancers involved in vocational training. The aim of the present study was to model bone mineral content (BMC) accruals and to determine whether circulating levels of oestrogens, growth hormone (GH), and insulin-like growth factor I (IGF-1) explain differences in bone mass gains between vocational dance students and matched controls.
The total of 67 vocational female dancers (VFDs) and 68 aged-matched controls (12.1 ± 1.9 years and 12.7 ± 2.0 years at baseline, respectively) were followed for two consecutive years (34 VFD and 31 controls remained in the study for the full duration). BMC was evaluated annually at impact [femoral neck (FN); lumbar spine (LS)] and non-impact sites (forearm) using DXA. Anthropometry, age at menarche (questionnaire), and hormone serum concentrations (immunoradiometric assays) were also assessed for the same period.
VFD demonstrated consistently reduced body weight (p < 0.001) and BMC at all three anatomical sites (p < 0.001) compared to controls throughout the study period. Menarche, body weight, GH, and IGF-1 were significantly associated with bone mass changes over time (p < 0.05) but did not explain group differences in BMC gains at impact sites (p > 0.05). However, body weight did explain the differences between groups in terms of BMC gains at the forearm (non-impact site).
Two consecutive years of vocational dance training revealed that young female dancers demonstrate consistently lower bone mass compared to controls at both impact and non-impact sites. The studied endocrine parameters do not seem to explain group differences in terms of bone mass gains at impact sites.
职业舞蹈训练中舞者的骨量发育知之甚少。本研究旨在建立骨矿物质含量（BMC）的积累模型，并确定循环雌激素、生长激素（GH）和胰岛素样生长因子 I（IGF-1）水平是否可以解释职业舞蹈学生和匹配对照组之间骨量增加的差异。
本研究共纳入 67 名职业女性舞者（VFD）和 68 名年龄匹配的对照组（基线时分别为 12.1±1.9 岁和 12.7±2.0 岁），随访时间为 2 年（34 名 VFD 和 31 名对照组全程完成研究）。使用 DXA 每年评估一次冲击部位（股骨颈[FN]；腰椎[LS]）和非冲击部位（前臂）的 BMC。同期还评估了人体测量学、初潮年龄（问卷调查）和激素血清浓度（免疫放射测定法）。
在整个研究期间，与对照组相比，VFD 始终表现出较低的体重（p<0.001）和所有三个解剖部位的 BMC（p<0.001）。初潮、体重、GH 和 IGF-1 与随时间变化的骨量变化显著相关（p<0.05），但不能解释 BMC 在冲击部位的增加方面的组间差异（p>0.05）。然而，体重可以解释两组在非冲击部位（前臂）的 BMC 增加差异。
连续 2 年的职业舞蹈训练表明，年轻女性舞者在冲击和非冲击部位的骨量均明显低于对照组。研究中涉及的内分泌参数似乎不能解释 BMC 在冲击部位的增加方面的组间差异。
