背景：男性耐力赛跑运动员在竞争季节的骨骼代谢研究很少。此外，日本选手有一个特殊的竞争赛季。本研究旨在调查日本男性耐力运动员骨转换标志物（BTMs）和其他激素的变化。
方法：我们研究了生化标志物，骨形成和吸收标记和性激素，使用双能X射线吸收法（DXA）的身体成分，和在竞争赛季的训练量。本研究分析了11名（年龄：24.0±4.3岁）日本男性耐力运动员。他们每年参加所有测量三次：基线（BL），后轨道期(PT)，和公路比赛期(RR)。
结果：RR（p=0.009，p=0.009）时的脂肪质量（FM）和体脂百分比（％体脂）低于BL。与BL相比，特异性骨碱性磷酸酶（BAP）在PT（p=0.004）和RR（p=0.004）降低。然而,骨吸收标记没有改变.PT时的游离睾酮(p=0.032)低于BL。与血液变量和身体成分或训练量没有相关性。
结论：日本男性耐力赛跑运动员的BAP和睾酮在比赛季节下降。然而,血液变量和训练量之间没有相关性.
BACKGROUND: The bone metabolism of male endurance runners during a competitive season has been little studied. Furthermore, Japanese runners have a special competitive season. This study aimed to investigate the change of bone turnover markers (BTMs) and other hormones in Japanese male endurance runners.
METHODS: We investigated biochemical markers, bone formation and resorption markers and sex hormones, body composition using dual-energy X-ray absorptiometry (DXA), and training volume during a competitive season. 11 (age: 24.0 ± 4.3 years) Japanese male endurance runners were analyzed in this study. They participated in all measurements three times a year: the baseline (BL), the post-track period (PT), and the road race period (RR).
RESULTS: Fat mass (FM) and percentage of body fat (% body fat) at RR (p = 0.009, p = 0.009) were lower than at BL. Specific bone alkaline phosphatase (BAP) decreased at PT (p = 0.004) and RR (p = 0.004) compared with BL. However, the bone resorption marker did not change. Free testosterone at PT (p = 0.032) was lower than BL. There was no correlation with blood variables and body composition or training volume.
CONCLUSIONS: BAP and testosterone in Japanese male endurance runners decreased during the competitive season. However, there was no correlation between blood variables and training volume.
