Baker Brent A
J Sport Rehabil. 2017 Apr;26(2):180-188. doi: 10.1123/jsr.2016-0075. Epub 2017 Jan 17.
Clinical Scenario: Even though chronological aging is an inevitable phenomenological consequence occurring in every living organism, it is biological aging that may be the most significant factor challenging our quality of life. Development of functional limitations, resulting from improper maintenance and restoration of various organ systems, ultimately leads to reduced health and independence. Skeletal muscle is an organ system that, when challenged, is often injured in response to varying stimuli. Overt muscle-strain injury can be traumatic, clinically diagnosable, properly managed, and a remarkably common event, yet our contemporary understanding of how age and environmental stressors affect the initial and subsequent induction of injury and how the biological processes resulting from this event are modifiable and, eventually, lead to functional restoration and healing of skeletal muscle and adjacent tissues is presently unclear. Even though the secondary injury response to and recovery from "contraction-induced" skeletal-muscle injury are impaired with aging, there is no scientific consensus as to the exact mechanism responsible for this event. Given the multitude of investigative approaches, particular consideration given to the appropriateness of the muscle-injury model, or research paradigm, is critical so that outcomes may be physiologically relevant and translational. In this case, methods implementing stretch-shortening contractions, the most common form of muscle movements used by all mammals during physical movement, work, and activity, are highlighted.
Understanding the fundamental evidence regarding how aging influences the responsivity of skeletal muscle to strain injury is vital for informing how clinicians approach and implement preventive strategies, as well as therapeutic interventions. From a practical perspective, maintaining or improving the overall health and tissue quality of skeletal muscle as one ages will positively affect skeletal muscle's safety threshold and responsivity, which may reduce incidence of injury, improve recovery time, and lessen overall fiscal burdens.
临床案例：尽管按时间顺序的衰老在每个生物体中都是不可避免的现象学后果，但生物衰老可能是挑战我们生活质量的最重要因素。各种器官系统维护和修复不当导致功能受限，最终会导致健康状况下降和独立性降低。骨骼肌是一个器官系统，在受到挑战时，常常会因各种刺激而受损。明显的肌肉拉伤损伤可能具有创伤性，可临床诊断，能得到妥善处理，且是相当常见的事件。然而，我们目前对于年龄和环境应激源如何影响损伤的初始及后续诱发，以及该事件引发的生物学过程如何可被改变并最终导致骨骼肌及相邻组织的功能恢复和愈合尚不清楚。尽管随着年龄增长，对“收缩诱导”的骨骼肌损伤的二次损伤反应及恢复会受损，但对于导致该事件的确切机制尚无科学共识。鉴于众多的研究方法，特别考虑肌肉损伤模型或研究范式的适用性至关重要，以便研究结果在生理上具有相关性且可转化。在这种情况下，重点介绍了采用拉长缩短收缩的方法，这是所有哺乳动物在身体运动、工作和活动中最常见的肌肉运动形式。
了解衰老如何影响骨骼肌对应变损伤的反应性的基本证据，对于指导临床医生如何采取和实施预防策略以及治疗干预至关重要。从实际角度来看，随着年龄增长维持或改善骨骼肌的整体健康和组织质量将对骨骼肌的安全阈值和反应性产生积极影响，这可能会降低损伤发生率、缩短恢复时间并减轻总体财政负担。
