Intervention to Enhance Lateral Balance Function and Prevent Falls in Aging

描述(申请人提供)：跌倒及其后果是老年人医疗护理中的主要问题之一。这项研究的长期目标是确定一种基于科学和机制的治疗干预措施的有效性，以改善老年人的平衡功能和预防跌倒。当人体平衡受到挑战时，保护步法是日常生活活动中防止跌倒的重要策略。许多有跌倒风险的老年人尤其难以成功地侧身行走，以此作为对侧向失去平衡的保护性反应。我们认为，与年龄相关的侧向平衡功能下降是由于髋关节外展-内收肌(AB-AD)肌肉力量(扭矩和功率)的神经机械(NM)限制造成的，这种下降是由于保护性踏步受损而导致的。此外，我们假设这些功能和NM损伤是可逆的，结合高强度诱导，阶梯训练和肌肉加强。具体目的是对四个训练组进行双盲、随机和对照试验，比较12周训练的效果，并通过确定：1)(A)腰部诱导台阶训练的效果，(B)髋部AB-AD肌肉强化，以及(C)综合台阶训练和肌肉强化计划的效果，比较(D)标准的灵活性和放松计划，包括最小强度的锻炼(对照)，对保护性台阶对外部平衡扰动的保护性台阶反应，通过i)多个平衡恢复步骤的数量，来评估其在3个月后的耐久性。和ii)第一步长度；2)与对照组相比，大强度踏步训练对髋关节AB-AD关节最大扭矩和功率的影响。第二个目标将评估保护性踏步表现和髋部AB-AD肌力是否区分a)在研究登记时通过回顾跌倒病史确定的跌倒者和b)不同干预组在训练后1年的预期跌倒频率。 公共卫生相关性：这项研究与公共卫生的相关性在于，它的重点是了解与年龄相关的跌倒的原因，并制定有效的干预措施，将跌倒对老年人造成的破坏性经济、社会和个人后果降至最低。

DESCRIPTION (provided by applicant): Falls and their consequences are among the major problems in the medical care of older individuals. The long-term goal of this research is to establish the efficacy of a scientifically grounded and mechanism-based therapeutic intervention for improving balance function and preventing falls in older people. When human balance is challenged, protective stepping is a vital strategy for preventing a fall during activities of daily life. Many older people at risk for falls have particular difficulties with successfully stepping sideways as a protective response to loss of balance in the lateral direction. We propose that age-related declines in lateral balance function through impaired protective stepping that precipitates falls, result from neuromechanical (NM) limitations in hip abductor-adductor (AB-AD) muscle strength (torque and power). Moreover, we hypothesize that these functional and NM impairments are reversible with combined, high intensity induced, step training and muscle strengthening. The specific aims are to conduct a double blind, randomized, and controlled trial with four training arms that will compare the effects of 12 weeks of training and assess its durability after 3 months of no training in community living older adults at risk for falls by determining: 1) the effect of (a) waist-pull induced step training, (b) hip AB-AD muscle strengthening, and (c) a combined step training and muscle strengthening program compared to (d) a standard flexibility and relaxation program involving minimal-intensity exercises (control) on the protective stepping response to an external balance perturbation, as measured by i) the number of multiple balance recovery steps, and ii) first step length; and 2) the effect of high intensity step training, with and without the strengthening intervention, compared to the control group on a) maximum hip AB- AD joint torque and power. A secondary aim will assess whether protective stepping performance and hip AB- AD muscle strength discriminate between a) fallers and non-fallers identified by retrospective fall history at the time of study enrollment, and b) the prospective fall frequency of the different intervention groups during 1-year follow-up post-training. PUBLIC HEALTH RELEVANCE: The relevance of this research to public health lies in its focus on understanding the causes of age-associated falls and on the development of effective interventions for minimizing the devastating economic, societal, and personal consequences of falls among older people.