Institute of Health and Biomedical Innovation, Queensland University of Technology, Queensland, Australia.
Med Sci Sports Exerc. 2012 Jan;44(1):12-7. doi: 10.1249/MSS.0b013e318227fa8c.
Eccentric exercise has become the treatment of choice for Achilles tendinopathy. However, little is known about the acute response of tendons to eccentric exercise or the mechanisms underlying its clinical benefit. This research evaluated the sonographic characteristics and acute anteroposterior (AP) strain response of control (healthy), asymptomatic, and symptomatic Achilles tendons to eccentric exercise.
Eleven male adults with unilateral midportion Achilles tendinopathy and nine control male adults without tendinopathy participated in the research. Sagittal sonograms of the Achilles tendon were acquired immediately before and after completion of a common eccentric rehabilitation exercise protocol and again 24 h later. Tendon thickness, echogenicity, and AP strain were determined 40 mm proximal to the calcaneal insertion.
Compared with the control tendon, both the asymptomatic and symptomatic tendons were thicker (P < 0.05) and hypoechoic (P < 0.05) at baseline. All tendons decreased in thickness immediately after eccentric exercise (P < 0.05). The symptomatic tendon was characterized by a significantly lower AP strain response to eccentric exercise compared with both the asymptomatic and control tendons (P < 0.05). AP strains did not differ in the control and asymptomatic tendons. For all tendons, preexercise thickness was restored 24 h after exercise completion.
These observations support the concept that Achilles tendinopathy is a bilateral or systemic process and structural changes associated with symptomatic tendinopathy alter fluid movement within the tendon matrix. Altered fluid movement may disrupt remodeling and homeostatic processes and represents a plausible mechanism underlying the progression of tendinopathy.
离心运动已成为治疗跟腱病的首选方法。然而，对于跟腱对离心运动的急性反应或其临床益处的机制知之甚少。本研究评估了正常（健康）、无症状和有症状的跟腱在离心运动后的超声特征和前-后（AP）应变的急性反应。
11 名男性单侧中段跟腱病患者和 9 名无肌腱病的男性健康对照者参与了这项研究。在完成一项常见的离心康复运动方案前后，立即获取跟腱的矢状超声图像，并在 24 小时后再次获取。在距跟骨插入处 40mm 处测量肌腱厚度、回声和 AP 应变。
与正常肌腱相比，无症状和有症状的肌腱在基线时均更厚（P<0.05）且回声更低（P<0.05）。所有肌腱在离心运动后立即变薄（P<0.05）。与无症状和正常肌腱相比，有症状的肌腱对离心运动的 AP 应变反应明显较低（P<0.05）。在正常和无症状的肌腱中，AP 应变没有差异。对于所有的肌腱，在运动完成后 24 小时，术前厚度得到恢复。
这些观察结果支持这样的概念，即跟腱病是一种双侧或系统性的过程，与症状性肌腱病相关的结构变化改变了肌腱基质内的液体流动。液体流动的改变可能会破坏重塑和动态平衡过程，这代表了肌腱病进展的一个合理机制。
