Suominen Harri
Department of Health Sciences, University of Jyväskylä, Finland.
Aging Clin Exp Res. 2006 Apr;18(2):85-93. doi: 10.1007/BF03327422.
The main function of bone is to provide the mechanical integrity for locomotion and protection; accordingly, bone mass and architecture are adjusted to control the strains produced by mechanical load and muscular activity. Age-related patterns involve peak bone mass during growth, a plateau in adulthood, and bone loss during aging. The decline in bone mass and structural integrity results in increased risk of fractures, particularly in post-menopausal women. Athletes competing in strength and power events, such as weight-lifting and jumping, have superior bone mass and structure compared with their untrained counterparts in all age groups. Exercise seems to be most effective during rapid growth, the average gain in bone mineral content (BMC) and density (BMD) in controlled trials being of the order of 2-5% per year. The net gain of BMD after exercise interventions among older people is modest, at a level of 1-3% per year, but it is not clear whether positive effects can be maintained over a longer time. Although aerobic exercise is important in maintaining overall health, the resistance type of muscle training may be more applicable to the basic rules of bone adaptation and site-specific effects of exercise, have more favorable effects in maintaining or improving bone mass and architecture, and be safe and feasible for older people. It has been suggested that there is an opportunity for resistance training, for improved effects on BMD in postmenopausal women in bones which have less daily loading. In addition to BMC and BMD, bone geometry and mass distribution may also change as a result of training and other treatment, such as hormonal replacement therapy, thereby further improving bone strength and reducing fracture risk. Appropriate training regimens may reduce the risk of falls and the severity of fall-related injuries, and also constitute potential therapy to improve functional ability and the quality of life in osteoporotic patients. However, further research is needed on dose-response relationships between exercise and bone strength, the feasibility of high-load, high-speed and impact-type of physical training, and the risks and benefits of intensive exercisein elderly individuals.
骨骼的主要功能是为运动和保护提供机械完整性；因此，骨量和骨结构会进行调整，以控制机械负荷和肌肉活动产生的应变。与年龄相关的模式包括生长期间的骨量峰值、成年期的平稳期以及衰老期间的骨质流失。骨量和结构完整性的下降会导致骨折风险增加，尤其是在绝经后女性中。参加力量和爆发力项目（如举重和跳跃）的运动员，在所有年龄组中，其骨量和骨结构都优于未受过训练的同龄人。运动在快速生长期间似乎最为有效，在对照试验中，骨矿物质含量（BMC）和密度（BMD）的平均年增长率约为2%至5%。老年人运动干预后的BMD净增加量适中，每年为1%至3%，但尚不清楚这种积极效果能否在更长时间内维持。尽管有氧运动对维持整体健康很重要，但肌肉抗阻训练可能更符合骨骼适应的基本规律以及运动的部位特异性效应，在维持或改善骨量和骨结构方面具有更有利的作用，并且对老年人来说安全可行。有人提出，对于绝经后女性中日常负荷较小的骨骼，抗阻训练有机会改善对BMD的影响。除了BMC和BMD外，骨几何形状和质量分布也可能因训练和其他治疗（如激素替代疗法）而发生变化，从而进一步提高骨骼强度并降低骨折风险。适当的训练方案可能会降低跌倒风险以及跌倒相关损伤的严重程度，还可能构成改善骨质疏松患者功能能力和生活质量的潜在疗法。然而，关于运动与骨骼强度之间的剂量反应关系、高负荷、高速和冲击式体育训练的可行性以及老年人高强度运动的风险和益处，仍需要进一步研究。
