Rheumatology Advance Access published online on July 22, 2008
Rheumatology, doi:10.1093/rheumatology/ken262
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
The mechanism for efficacy of eccentric loading in Achilles tendon injury; an in vivo study in humans
1Department of Sport and Exercise Medicine, Royal National Orthopaedic Hospital, Stanmore, 2Defence Medical Rehabilitation Centre, Epsom, 3Structure and Motion Laboratory, The Royal Veterinary College, Hatfield, UK and 4School of Physiotherapy and Exercise Science, Griffith University, Gold Coast, Australia.
Correspondence to:
J. D. Rees, Defence Medical Rehabilitation Centre, Headley Court, Epsom, Surrey KT18 6JN, UK. E-mail: j.rees{at}doctors.org.uk
 |
Abstract |
|---|
Objective. Degenerative disorders of tendons present an enormous clinical challenge. They are extremely common, prone to recur and existing medical and surgical treatments are generally unsatisfactory. Recently eccentric, but not concentric, exercises have been shown to be highly effective in managing tendinopathy of the Achilles (and other) tendons. The mechanism for the efficacy of these exercises is unknown although it has been speculated that forces generated during eccentric loading are of a greater magnitude. Our objective was to determine the mechanism for the beneficial effect of eccentric exercise in Achilles tendinopathy.
Methods. Seven healthy volunteers performed eccentric and concentric loading exercises for the Achilles tendon. Tendon force and length changes were determined using a combination of motion analysis, force plate data and real-time ultrasound.
Results. There was no significant difference in peak tendon force or tendon length change when comparing eccentric with concentric exercises. However, high-frequency oscillations in tendon force occurred in all subjects during eccentric exercises but were rare in concentric exercises (P < 0.0001).
Conclusion. These oscillations provide a mechanism to explain the therapeutic benefit of eccentric loading in Achilles tendinopathy and parallels recent evidence from bone remodelling, where the frequency of the loading cycles is of more significance than the absolute magnitude of the force.
KEY WORDS: Tendon, Eccentric exercise, Efficacy
Submitted 16 March 2008;
revised version accepted 17 June 2008.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  C. Kaeding and T. M. Best Tendinosis: Pathophysiology and Nonoperative Treatment Sports Health: A Multidisciplinary Approach, July 1, 2009; 1(4): 284 - 292. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G T Allison and C Purdam Eccentric loading for Achilles tendinopathy -- strengthening or stretching? Br. J. Sports Med., April 1, 2009; 43(4): 276 - 279. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Knobloch Comment on: The mechanism for efficacy of eccentric loading in Achilles tendon injury: an in vivo study in humans Rheumatology, February 1, 2009; 48(2): 202 - 203. [Full Text] [PDF]
|
|
|
|
|
|
N. Maffulli and U. G. Longo How do eccentric exercises work in tendinopathy? Rheumatology, October 1, 2008; 47(10): 1444 - 1445. [Full Text] [PDF]
|
|