DXA Unit, Carnegie Research Institute, Leeds Metropolitan University, Leeds, United Kingdom.
Clin J Sport Med. 2011 Nov;21(6):521-9. doi: 10.1097/JSM.0b013e3182377257.
To evaluate bone mineral density (BMD) by age in premenopausal elite long-distance runners at 2 time points, 5.02 ± 0.5 years apart.
Follow-up study.
University Research Institute.
Twenty-three elite-level distance runners (baseline age, 24.9 ± 3.9 years; body mass index, 18.7 ± 1.1; running distance, 89.3 ± 19.4 km/wk) participated in the study.
Dual-energy x-ray absorptiometry (iDXA; GE Healthcare)-derived BMD z-scores for the total body (TB), lumbar spine (LS) (L2-L4), and proximal femur. A z-score of <-1.0 indicated low BMD by age.
Lumbar spine BMD z-scores had increased significantly by follow-up for all runners (baseline, -1.1 ± 0.9; follow-up, -0.7 ± 0.7; P = 0.04) and for formerly amenorrheic runners with restored menstruation (n = 10; baseline, -1.5 ± 0.9; follow-up, -0.9 ± 0.6; P = 0.03). Total body, but not proximal femur z-scores, had also increased (P < 0.05). Improvements in z-scores correlated with an increased body fat (LS: R2 = 0.27; TB: R2 = 0.35; P < 0.01) and menstrual history score (LS: R2 = 0.36; TB: R2 = 0.27; P < 0.05). There were no associations with lean mass or running volume at any skeletal site (P = 0.07-0.89).
Low BMD by age in highly-trained female runners may be at least partially reversible before the age of 30 years, even when competitive running is continued. This seems to be related to restored menstruation and an increased body fat. Further larger studies are required to clarify our findings.
评估 23 名高水平长跑运动员在两个时间点的骨密度（BMD），两次测量相隔 5.02±0.5 年。
随访研究。
大学研究所。
23 名高水平长跑运动员（基线年龄 24.9±3.9 岁；体重指数 18.7±1.1；每周跑步距离 89.3±19.4 公里）参与了研究。
双能 X 线吸收法（iDXA；GE 医疗保健）得出的全身（TB）、腰椎（LS）（L2-L4）和股骨近端的 BMD z 分数。z 分数<-1.0 表示按年龄计算的低 BMD。
所有运动员的腰椎 BMD z 分数在随访时均显著增加（基线：-1.1±0.9；随访：-0.7±0.7；P=0.04），月经恢复的曾经闭经的运动员（n=10）的 BMD z 分数也显著增加（基线：-1.5±0.9；随访：-0.9±0.6；P=0.03）。全身，而不是股骨近端的 z 分数也有所增加（P<0.05）。z 分数的改善与体脂增加（LS：R2=0.27；TB：R2=0.35；P<0.01）和月经史评分（LS：R2=0.36；TB：R2=0.27；P<0.05）相关。在任何骨骼部位，与瘦体重或跑步量均无关联（P=0.07-0.89）。
在 30 岁之前，即使继续进行竞技跑步，高度训练的女性跑步者的年龄相关低骨密度可能至少部分是可逆的。这似乎与月经恢复和体脂增加有关。需要进一步的更大规模研究来阐明我们的发现。
