Laabes E P, Vanderjagt D J, Obadofin M O, Sendeht A J, Glew R H
Department of Family Medicine, Jos University Teaching Hospital, Jos, Nigeria.
J Sports Med Phys Fitness. 2008 Dec;48(4):502-8.
The mean daily calcium intake of adult Nigerians is reportedly low, and animal studies have shown that exercise-induced changes in the bones of growing mice are gender specific. We therefore sought to describe calcaneal broadband ultrasound attenuation (BUA), speed of sound (SOS), stiffness index (SI) and SI-based T-scores in a cohort of Nigerian female athletes; to assess the correlation of SI with energy expenditure; and to compare mean SI values between sports.
We recruited 52 female athletes in 10 sporting categories, and recorded their anthropometric data. Activity levels were estimated using a questionnaire. Bone density was assessed using calcaneal ultrasound.
The mean age of athletes was 21+/-4 years (range 15-39 years). The mean body mass index (BMI) was 22.0+/-3.5 kg/m2, and was not different between the sub-group of footballers/runners (21.3+/-1.7 kg/m2) and other athletes (23.1+/-4.8 kg/m2, P=0.06). The mean energy expenditure was 32.2+/-9.5 kcal/kg/ day, and was not different between the sub-group of footballers/runners (30.8+/-9.2 kcal/kg/day) and other athletes (34.3+/-9.7 kcal/kg/day, P=0.19). The mean BUA of the athletes was 135+/-14 dB/MHz, the mean SOS was 1597+/-13 m/s, the mean SI was 118+/-15, and the median SI-based T-score was +1.1 (-1.6 to +3.53). The means of all ultrasound parameters were not significantly different between footballers/runners and other sportswomen.
Consistent physical training may improve calcaneal SI of black females by one, and potentially by as much as three T-score units. Training intensity, rather than the qualitative aspects of a sport, appears to be a major determinant of SI in female Nigerian athletes.
据报道，成年尼日利亚人的每日钙摄入量较低，并且动物研究表明，运动引起的生长中小鼠骨骼变化具有性别特异性。因此，我们试图描述一组尼日利亚女运动员的跟骨宽带超声衰减（BUA）、声速（SOS）、硬度指数（SI）以及基于SI的T值；评估SI与能量消耗的相关性；并比较不同运动项目之间的平均SI值。
我们招募了10个运动项目的52名女运动员，并记录了她们的人体测量数据。使用问卷估计活动水平。使用跟骨超声评估骨密度。
运动员的平均年龄为21±4岁（范围15 - 39岁）。平均体重指数（BMI）为22.0±3.5kg/m²，足球运动员/跑步运动员亚组（21.3±1.7kg/m²）与其他运动员（23.1±4.8kg/m²，P = 0.06）之间无差异。平均能量消耗为32.2±9.5kcal/kg/天，足球运动员/跑步运动员亚组（30.8±9.2kcal/kg/天）与其他运动员（34.3±9.7kcal/kg/天，P = 0.19）之间无差异。运动员的平均BUA为135±14dB/MHz，平均SOS为1597±13m/s，平均SI为118±15，基于SI的T值中位数为 +1.1（-1.6至 +3.53）。足球运动员/跑步运动员与其他女运动员之间所有超声参数的平均值无显著差异。
持续的体育锻炼可能使黑人女性的跟骨SI提高1个，甚至可能高达3个T值单位。训练强度而非运动的质量方面似乎是尼日利亚女运动员SI的主要决定因素。
