Department of Family Medicine, Jos University Teaching Hospital, PMB 2076, Jos, Nigeria.
Nutr Metab (Lond). 2008 May 20;5:13. doi: 10.1186/1743-7075-5-13.
Lifestyle, genetics and environmental factors are established determinants of bone density. We aimed to describe the bone characteristics of competitive top-ranked Nigerian male athletes using calcaneal ultrasound and to assess whether intensive training promotes higher bone density in an environment with reportedly low calcium intake; to compare the bone characteristics of footballers with runners and other sportsmen; and to assess the correlation of stiffness index (SI) with activity level, since energy expenditure correlates with length of training and by extension, magnitude of skeletal loading.
We recruited 102 male athletes: these included football (n = 68), running (n = 15), handball (n = 7), taekwando (n = 6), cycling (n = 2), judo (1), badminton (1) and high jump (1). Anthropometric data were first recorded on a structured form and energy expenditure was indirectly estimated with a validated questionnaire. Bone density was assessed using the Lunar Achilles+ calcaneal ultrasonometer.
The mean age of athletes was 25 +/- 6 years. The means of BMI and energy expenditure were 21.9 +/- 2.0 kg/m2 and 35.0 +/- 13.7 kcal/kg/day, respectively. Footballers were younger (p < 0.001) and heavier (p < 0.001) than runners. Football was a significant determinant of BUA independent of age, BMI and energy expenditure (p = 0.001). Football was also a significant determinant of SOS independent of age, height, weight and BMI (p < 0.001). The mean SI was 127 +/- 16 and the median T-score was 0.82 (-1.88, 3.35). The mean SI of footballers (130 +/- 15), runners (130 +/- 12) and other sportsmen (115 +/- 18) differed significantly (p = 0.001). Multivariate analyses revealed that football (p < 0.001) and running (p < 0.001) were significant determinants of SI independent of age and BMI. Footballers when compared with other sportsmen had a higher mean SI independent of age and BMI (p < 0.001). Age was not correlated with SI. The median T-score of footballers, 0.94 (-1.0, 3.35) was higher than that of other sportsmen.
Repetitive skeletal loading at the heel has the potential to improve bone density in black male athletes. The magnitude of increase may be higher in medium impact sports such as soccer and running compared with low or non-impact sports such as judo or taekwando, and is independent of age and BMI. However, future longitudinal data will be required to support our observations.
生活方式、遗传和环境因素是确定骨密度的因素。我们旨在使用跟骨超声描述尼日利亚顶级男性运动员的骨骼特征，并评估在据称低钙摄入的环境中，强化训练是否会促进更高的骨密度；比较足球运动员与跑步运动员和其他运动员的骨骼特征；并评估刚度指数（SI）与活动水平的相关性，因为能量消耗与训练时间有关，从而与骨骼负荷的程度有关。
我们招募了 102 名男性运动员：其中包括足球（n = 68）、跑步（n = 15）、手球（n = 7）、跆拳道（n = 6）、自行车（n = 2）、柔道（n = 1）、羽毛球（n = 1）和跳高（n = 1）。首先在结构化表格上记录人体测量数据，并使用经过验证的问卷间接估计能量消耗。使用 Lunar Achilles+跟骨超声仪评估骨密度。
运动员的平均年龄为 25 +/- 6 岁。BMI 和能量消耗的平均值分别为 21.9 +/- 2.0 kg/m2 和 35.0 +/- 13.7 kcal/kg/天。足球运动员比跑步运动员更年轻（p < 0.001）且更重（p < 0.001）。足球是独立于年龄、BMI 和能量消耗的 BUA 的重要决定因素（p = 0.001）。足球也是独立于年龄、身高、体重和 BMI 的 SOS 的重要决定因素（p < 0.001）。平均 SI 为 127 +/- 16，中位数 T 评分为 0.82（-1.88，3.35）。足球运动员（130 +/- 15）、跑步运动员（130 +/- 12）和其他运动员（115 +/- 18）的平均 SI 差异有统计学意义（p = 0.001）。多变量分析显示，足球（p < 0.001）和跑步（p < 0.001）是独立于年龄和 BMI 的 SI 的重要决定因素。与其他运动员相比，足球运动员的平均 SI 更高，独立于年龄和 BMI（p < 0.001）。年龄与 SI 不相关。足球运动员的中位数 T 评分，0.94（-1.0，3.35）高于其他运动员。
脚跟处的重复骨骼负荷有可能提高黑人男性运动员的骨密度。与低冲击或非冲击运动（如柔道或跆拳道）相比，中冲击运动（如足球和跑步）的增加幅度可能更高，且独立于年龄和 BMI。然而，未来的纵向数据将支持我们的观察。
