Dynamic Lumbar-Pelvic Coordination in the Low Back During Lifting

描述(申请人提供)：腰痛(LBP)是一种常见且代价高昂的公共和职业健康问题，与工作场所重复举重任务的表现有关。找出更好的举重策略，并对工人和下腰痛患者进行这些策略的培训，可能有助于减少LBP的发生率。建议的研究目的是比较不同的抬起策略对腰椎力学(特别是机械效率)在抬起任务中的影响。我们研究的长期目标是确定安全的举重机制，并改进康复方法，以纠正LBP患者在举重过程中的身体力学。这项研究将集中于更好地了解拉伸-缩短循环在举重任务期间可能在腰椎力学中所起的潜在作用。伸展缩短在一些重复和循环的动作(跑步和跳跃)中已经显示出来，以提高运动的机械效率。伸展缩短在腰部的作用还没有被研究过。腰椎-骨盆协调研究，包括作者的初步研究，已经显示出与伸展缩短机制相一致的滞后模式。虽然拉伸缩短可以提高机械效率，使举重变得更容易，但它也会导致肌肉偏心收缩和脊柱弯曲，从而可能导致受伤。在这项研究中，将调查拉伸缩短在腰椎力学中的存在和作用。我们将研究不同的腰盆协调策略(骨盆先(高位腰屈)、中位和骨盆末位(低位腰屈))的循环提举任务的机械效率。我们还将研究新手和有经验的举重运动员的自选协调模式。据推测，那些有举重锻炼经验的人会优先选择更中性的举重策略来避免受伤，即使它的能量效率较低。如果这项研究成功，未来的研究目标将是将这些想法应用到临床环境中，并调查培训LBP患者避免伸展缩短协调模式，并帮助他们建立耐力以使用其他协调模式是否有助于防止LBP损伤的复发。

DESCRIPTION (provided by applicant): Low back pain (LBP) is a common and costly public and occupational health problem that has been associated with the performance of repetitive lifting tasks in the workplace. Identifying better lifting strategies and training workers and low back pain patients in these strategies could serve to reduce the incidence LBP. The objective of the proposed study is to compare the effects of different lifting strategies on lumbar mechanics (in particular mechanical efficiency) during a lifting task. The long-term goal of our research is to identify safe lifting mechanics and improve rehabilitation approaches for correct body mechanics during lifting in people with LBP. This study will focus on developing a better understanding of the potential role stretch-shortening cycles may play in lumbar mechanics during a lifting task. Stretch-shortening has been shown in a number of repetitive and cyclic movements (running and jumping) to improve mechanical efficiency of the movement. The role of the stretch-shortening in the low back has not been examined. Lumbar-pelvic coordination studies, including preliminary studies by the authors, have shown patterns of hysteresis that would be consistent with a stretch-shortening mechanism. While stretch-shortening may improve mechanical efficiency, making lifting easier, it also will result in eccentric muscle contraction and spine flexion that could cause injury. In this study, the existence and role of stretch-shortening in lumbar mechanics will be investigated. We will investigate the mechanical efficiency of cyclic lifting tasks with different lumbar-pelvic coordination strategies (pelvis-first (high lumbar flexion), neutral, and pelvis-last (low lumbar flexion)). We will also examine the self- selected coordination patterns of novice and experienced lifters. It is hypothesized that those with experience in weight lifting for exercise will preferentially select a more neutral lifting strategy to avoid injury, even though it is less energy efficient. If this research is successful, future research goals will be to take these ideas into the clinical setting and investigate whether training LBP patients to avoid stretch-shortening coordination patterns and helping them build the endurance to be able to use other coordination patterns might help prevent recurrence of LBP injuries.