Department of Physical Therapy, Indiana University School of Health and Human Sciences, Indianapolis, IN, USA.
Department of Foods and Nutrition, University of Georgia, Athens, GA, USA.
J Bone Miner Res. 2018 Nov;33(11):1940-1947. doi: 10.1002/jbmr.3550. Epub 2018 Aug 27.
Increases in 25-hydroxyvitamin D concentrations are shown to improve strength in adults; however, data in pediatric populations are scant and equivocal. In this ancillary study of a larger-scale, multi-sited, double-blind, randomized, placebo-controlled vitamin D intervention in US children and adolescents, we examined the associations between changes in vitamin D metabolites and changes in muscle mass, strength, and composition after 12 weeks of vitamin D supplementation. Healthy male and female, black and white children and adolescents between the ages of 9 and 13 years from two US states (Georgia 34°N and Indiana 40°N) were enrolled in the study and randomly assigned to receive an oral vitamin D dose of 0, 400, 1000, 2000, or 4000 IU/d for 12 weeks between the winter months of 2009 to 2011 (N = 324). Analyses of covariance, partial correlations, and regression analyses of baseline and 12-week changes (post-baseline) in vitamin D metabolites (serum 25(OH)D, 1,25(OH) D, intact parathyroid hormone [iPTH]), and outcomes of muscle mass, strength, and composition (total body fat-free soft tissue [FFST], handgrip strength, forearm and calf muscle cross-sectional area [MCSA], muscle density, and intermuscular adipose tissue [IMAT]) were assessed. Serum 25(OH)D and 1,25(OH) D, but not iPTH, increased over time, as did fat mass, FFST, forearm and calf MCSA, forearm IMAT, and handgrip strength (p < 0.05). Vitamin D metabolites were not associated with muscle strength at baseline nor after the 12-week intervention. Changes in serum 25(OH)D correlated with decreases in forearm IMAT, whereas changes in serum iPTH predicted increases in forearm and calf MCSA and IMAT (p < 0.05). Overall, increases in 25(OH)D did not influence muscle mass or strength in vitamin D-sufficient children and adolescents; however, the role of iPTH on muscle composition in this population is unknown and warrants further investigation. © 2018 American Society for Bone and Mineral Research.
维生素 D 浓度的增加被证明可以提高成年人的力量；然而，儿科人群的数据很少且存在争议。在这项针对美国儿童和青少年的更大规模、多地点、双盲、随机、安慰剂对照维生素 D 干预的辅助研究中，我们研究了 12 周维生素 D 补充后维生素 D 代谢物的变化与肌肉质量、力量和组成的变化之间的关系。来自美国两个州（佐治亚州 34°N 和印第安纳州 40°N）的年龄在 9 至 13 岁之间的健康男性和女性、黑人和白人儿童和青少年被纳入研究，并随机分配接受口服维生素 D 剂量为 0、400、1000、2000 或 4000 IU/d，持续 12 周，时间为 2009 年至 2011 年的冬季（N=324）。采用协方差分析、偏相关分析和回归分析，对维生素 D 代谢物（血清 25（OH）D、1,25（OH）D、完整甲状旁腺激素[iPTH]）的基线和 12 周变化（基线后）以及肌肉质量、力量和组成的结果（全身无脂肪软组织[FFST]、握力、前臂和小腿肌肉横截面积[MCSA]、肌肉密度和肌间脂肪组织[IMAT]）进行评估。血清 25（OH）D 和 1,25（OH）D 随时间增加，甲状旁腺激素[iPTH]也增加，脂肪量、FFST、前臂和小腿 MCSA、前臂 IMAT 和握力也增加（p<0.05）。维生素 D 代谢物与基线时的肌肉力量无关，也与 12 周干预后的肌肉力量无关。血清 25（OH）D 的变化与前臂 IMAT 的减少相关，而血清 iPTH 的变化预测前臂和小腿 MCSA 和 IMAT 的增加（p<0.05）。总的来说，在维生素 D 充足的儿童和青少年中，25（OH）D 的增加不会影响肌肉质量或力量；然而，该人群中 iPTH 对肌肉成分的作用尚不清楚，需要进一步研究。© 2018 美国骨矿研究协会。
