Ginty F, Rennie K L, Mills L, Stear S, Jones S, Prentice A
MRC Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, CB1 9NL, United Kingdom.
Bone. 2005 Jan;36(1):101-10. doi: 10.1016/j.bone.2004.10.001. Epub 2004 Nov 24.
The incidence of hip and forearm fracture in elderly men in the United Kingdom is a public health issue, but there is limited knowledge on lifestyle factors affecting male bone health. The aim of this cross-sectional study was to evaluate the relationships between whole body and regional bone mineral status and self-reported participation time in no-, low-, moderate-, and high-impact activities and fitness measurements in 16- to 18-year-old boys. One hundred twenty-eight boys underwent absorptiometry (DXA) measurements (Hologic QDR 1000W) of bone mineral content (BMC), bone area (BA), and bone mineral density (BMD) at the whole body, hip, spine, and forearm. They also completed the EPIC (European Prospective Investigation of Cancer) physical activity questionnaire, which allowed categorization of activities according to impact and aerobic intensity. Fitness and strength were assessed in each subject using estimated VO2 max, grip strength, and back strength. Significant positive relationships were found between BMC, BA, and BMD and the fitness and strength measurements and participation time in high-impact sports at most skeletal sites. The relationships were further examined after adjustment of BMC for height, weight, and bone area, thereby minimizing the influence of body and bone size on these relationships. VO2 max was a significant positive determinant of size-adjusted BMC at the whole body, the ultradistal and one-third radius, and all the hip sites, except the trochanter. Size-adjusted BMC at the forearm sites and trochanter was significantly positively associated with grip strength. Size-adjusted BMC at the whole body and all the hip sites was significantly positively associated with time spent at high-impact activities. Differences in size-adjusted BMC across thirds of time spent at high-impact activities were also examined. Boys in the highest third of high-impact activity had significantly greater size-adjusted whole body BMC and total hip BMC compared to subjects in the lowest third [+3.4 (1.2)% for whole body and +8.5 (2.2)% for hip, both P = 0.001]. Boys in the highest third of high-impact activity spent most activity time jogging, playing tennis, football and rugby, basketball, and exercising with weights. Back strength and lean mass were significantly greater in subjects in the highest third compared to those in the middle (P = 0.02) and lowest third (P = 0.03). No significant differences were found between subjects in each third of high-impact activity for potential confounders including TV viewing, calcium intake, body fat, and height. These findings indicate that participation of male adolescents in a range of high-impact activities for 1 h or more a day is associated with greater bone size and mineral content, especially at the hip.
在英国，老年男性髋部和前臂骨折的发生率是一个公共卫生问题，但对于影响男性骨骼健康的生活方式因素，人们了解有限。这项横断面研究的目的是评估16至18岁男孩的全身和局部骨矿物质状况与自我报告的无冲击、低冲击、中等冲击和高冲击活动的参与时间以及体能测量指标之间的关系。128名男孩接受了骨密度仪（DXA，Hologic QDR 1000W）测量，以测定全身、髋部、脊柱和前臂的骨矿物质含量（BMC）、骨面积（BA）和骨密度（BMD）。他们还完成了EPIC（欧洲癌症前瞻性调查）体力活动问卷，该问卷可根据冲击和有氧强度对活动进行分类。使用估计的最大摄氧量、握力和背部力量对每个受试者的体能和力量进行评估。在大多数骨骼部位，发现BMC、BA和BMD与体能和力量测量指标以及高冲击运动的参与时间之间存在显著的正相关关系。在对BMC进行身高、体重和骨面积调整后，进一步检验了这些关系，从而最大限度地减少身体和骨骼大小对这些关系的影响。最大摄氧量是全身、尺骨远端和三分之一处以及除转子外所有髋部部位经大小调整后的BMC的显著正决定因素。前臂部位和转子处经大小调整后的BMC与握力显著正相关。全身和所有髋部部位经大小调整后的BMC与高冲击活动的时间显著正相关。还检验了高冲击活动时间三等分中经大小调整后的BMC差异。高冲击活动时间处于最高三分之一的男孩与处于最低三分之一的受试者相比，经大小调整后的全身BMC和全髋BMC显著更高[全身为+3.4（1.2）%，髋部为+8.5（2.2）%，P均=0.001]。高冲击活动时间处于最高三分之一的男孩大部分活动时间用于慢跑、打网球、踢足球和橄榄球、打篮球以及举重锻炼。与处于中间三分之一（P = 0.02）和最低三分之一（P = 0.03）的受试者相比，处于最高三分之一的受试者背部力量和瘦体重显著更大。在高冲击活动的每个三分之一时间段内，包括看电视、钙摄入量、体脂和身高在内的潜在混杂因素在受试者之间未发现显著差异。这些发现表明，男性青少年每天参与1小时或更长时间的一系列高冲击活动与更大的骨骼大小和矿物质含量相关，尤其是在髋部。
