Nurmi-Lawton Jaana A, Baxter-Jones Adam D, Mirwald Robert L, Bishop Jacki A, Taylor Patricia, Cooper Cyrus, New Susan A
Centre for Nutrition and Food Safety, School of Biomedical and Molecular Sciences, University of Surrey, Guildford, United Kingdom.
J Bone Miner Res. 2004 Feb;19(2):314-22. doi: 10.1359/JBMR.0301222. Epub 2003 Dec 16.
The skeletal effects from intensive exercise throughout puberty are undefined. Forty-five female gymnasts and 52 controls were studied over 3 years, including a heredity aspect. The effects of size, maturity, exercise, and diet were identified using a multilevel regression model. Results demonstrated sustained skeletal benefits resulting from exercise throughout all stages of pubertal development.
Weight-bearing exercise is beneficial for peak bone mass development. However, whether skeletal benefits achieved with exercise are maintained if training remains intensive throughout the pubertal years is not entirely clear. The influence of familial resemblance for bone mass remains undefined in physically active versus inactive children. The aim of this study was to investigate the long-term influences of impact-loading exercise on bone quantity and quality in young females after controlling for growth, maturation, and hereditary factors.
At baseline, 45 gymnasts (G) and 52 normally active controls (C) 8-17 years of age were recruited. Anthropometry, diet, physical activity, and quantitative ultrasound (QUS) were measured annually for 3 consecutive years. DXA scans of total body (TB) and lumbar spine (LS) bone mineral content (BMC) and density (BMD) were taken three times at 1-year intervals. A multilevel regression model was fitted, and the independent effects of body size, maturity, physical activity, and diet were identified over time. To assess heredity influences, 27 G mothers and 26 C mothers volunteered for cross-sectional measurements of anthropometry, QUS, and BMC/BMD.
Gymnasts were smaller and lighter (as were their mothers) than controls, but they had significantly higher QUS and axial and appendicular BMC and BMD, with > 170 g more bone mineral in TB across puberty (after adjustment for maturity [years from peak height velocity], height, weight, energy, and protein intake). Gymnasts had up to 24-51% higher BMC and 13-28% higher BMD, depending on skeletal site. These results provide evidence of sustained skeletal benefits from impact-loading exercise, which are unlikely to result entirely from heredity, throughout pubertal years.
青春期全程高强度运动对骨骼的影响尚不明确。对45名女性体操运动员和52名对照者进行了为期3年的研究，其中包括遗传方面的研究。使用多水平回归模型确定了体型、成熟度、运动和饮食的影响。结果表明，在青春期发育的各个阶段，运动都能持续给骨骼带来益处。
负重运动有利于峰值骨量的发展。然而，如果在整个青春期持续进行高强度训练，运动所带来的骨骼益处是否能得以维持尚不完全清楚。在身体活跃和不活跃的儿童中，家族相似性对骨量的影响仍不明确。本研究的目的是在控制生长、成熟度和遗传因素后，调查冲击负荷运动对年轻女性骨骼数量和质量的长期影响。
在基线时，招募了45名8至17岁的体操运动员（G组）和第52名正常活动的对照者（C组）。连续3年每年测量人体测量学指标、饮食、身体活动和定量超声（QUS）。每隔1年对全身（TB）和腰椎（LS）的骨矿物质含量（BMC）和骨密度（BMD）进行三次双能X线吸收法扫描。拟合了一个多水平回归模型，并确定了随着时间推移体型、成熟度、身体活动和饮食的独立影响。为了评估遗传影响，27名G组母亲和26名C组母亲自愿接受人体测量学、QUS以及BMC/BMD的横断面测量。
体操运动员（及其母亲）比对照者体型更小、体重更轻，但她们的QUS以及轴向和附属骨骼的BMC和BMD显著更高，青春期期间全身的骨矿物质比对照者多170克以上（在调整了成熟度[距身高增长峰值速度的年数]、身高、体重、能量和蛋白质摄入量之后）。根据骨骼部位不同，体操运动员的BMC高出24%至51%，BMD高出13%至28%。这些结果证明，在整个青春期，冲击负荷运动能持续给骨骼带来益处，且这一益处不太可能完全由遗传因素导致。
