DETERMINANTS OF BONE HEALTH IN YOUNG GYMNASTS

描述：有人担心儿童参与艺术活动 体操训练对生长发育有不良影响。 虽然有一种普遍的观念认为体操的参与与 到糟糕的饮食、饮食紊乱、继发性闭经和骨质流失， 缺乏支持这一论点的科学证据。尽管低迷 钙，限制能量的饮食和月经紊乱的病史， 大学生体操运动员的骨密度(BMD)高于对照组。 经前体操运动员骨密度升高提示早期体操 青春期开始前的训练对儿童的发展至关重要。 峰值骨量。然而，增强的BMD可能以前就存在 训练从来没有开始过。调查员的主要假设是 从小开始高水平的艺术体操训练将会 增加骨密度。第二个假设是高水平的艺术体操 从小开始的训练不会促进能量限制，低 钙摄入量或进食障碍的相关心理症状。 还有人担心，参加体操运动会导致 高度。预计身高和生长速度的降低以及更低 体操运动员体内存在胰岛素样生长因子-1(IGF-1)水平。 然而，随着时间的推移，还没有研究检测体操运动员体内的IGF-1，也没有 对体操运动员身高和生长因子的同步变化进行了研究。 此外，还没有研究确定生长因子水平是否在 体操运动员在训练开始前的水平低于非体操运动员。三分之一 假设是高水平的艺术体操训练开始了 年轻时会减慢生长速度，改变IGF-1和IGF-1的结合 蛋白3(IGFBP-3)。 为了检验这些假设，我们将对女孩(5-8岁)进行检查 他们头两年的体操训练。的具体目标 这些建议是：1)确定以前是否存在骨密度升高 体操训练开始；2)及早确定影响 体操训练对骨密度、膳食摄入量及相关心理的影响 饮食行为紊乱的症状；3)确定 体操运动员骨生长因子、骨标记物测定及骨密度测定 周转和性成熟；以及4)确定两年的 体操训练会降低成长速度或改变成长因素。 这项研究将对体操活动的影响提供洞察力 在很小的时候就开始对儿童的骨骼和生长发育进行研究。

DESCRIPTION: There is concern that child participation in artistic gymnastics training has adverse consequences on growth and development. While there is a widespread notion that gymnastics participation is linked to poor diets, disordered eating, secondary amenorrhea, and bone loss, the scientific evidence supporting this contention is lacking. Despite low calcium, energy restricted diets and a history of menstrual disruptions, college gymnasts have higher bone mineral density (BMD) than controls. Elevated BMD in premenstrual gymnasts suggests that early gymnastics training, prior to the onset of puberty, is critical in the development of peak bone mass. However, it is possible the enhanced BMD exists before training ever begins. The investigator's main hypothesis is that high-levels of artistic gymnastics training initiated at a young age will enhance BMD. A second hypothesis is that high-levels of artistic gymnastics training initiated at a young age will not promote energy restriction, low calcium intakes or relevant psychological symptoms of disordered eating. There is also concern that gymnastics participation results in a reduced height. A reduction in predicted height and growth velocity and lower insulin-like growth factor 1(IGF-1) levels have been found in gymnasts. However, no studies have examined IGF-1 in gymnasts over time, nor have simultaneous changes in height and growth factors been examined in gymnasts. In addition, no studies have determined whether growth factor levels in gymnasts are lower than nongymnasts prior to the onset of training. A third hypothesis is that high-levels of artistic a gymnastics training initiated at a young age will blunt growth velocity and alter IGF-1 and IGF-1 binding protein-3 (IGFBP-3). To test these hypotheses, girls (5-8 years of age) will be examined during their first two years of gymnastics training. The specific objectives of the proposal are: 1) to determine if elevated BMD is present before gymnastics training is initiated; 2) to determine the impact of early gymnastics training on BMD, dietary intakes and relevant psychological symptoms of disordered eating behavior; 3) to determine the basis for elevated BMD in gymnasts by assessing growth factors, markers of bone turnover and sexual maturation; and 4) to determine if two years of gymnastics training will blunt growth velocity or alter growth factors. This study will provide insight into the impact of gymnastics activity initiated at an early age on bone and growth in children.