Partial protection against muscle damage by eccentric actions at short muscle lengths

Med Sci Sports Exerc. 2005 May;37(5):746-53. doi: 10.1249/01.mss.0000162691.66162.00.


Purpose: This study investigated the hypothesis that maximal eccentric actions at a short muscle length would fail to confer a protective effect against muscle damage induced by maximal eccentric exercise at a long muscle length.

Methods: Eleven males performed 24 maximal eccentric actions of the nondominant elbow flexors over a short extension range from an elbow joint angle of 0.87-1.74 rad (S-ECC) followed 4 wk later by eccentric actions at a long range of 2.27-3.14 rad (L-ECC). A second group of 11 males performed L-ECC on two occasions using the nondominant arm separated by 4 wk. Changes in maximal isometric strength, range of motion, upper arm circumference, muscle soreness, plasma creatine kinase and aspartate aminotransferase activities, and B-mode ultrasound images were compared between bouts and between groups by two-way repeated measures ANOVA.

Results: All measures changed significantly (P < 0.01) after the first bout; however, the effects were significantly (P < 0.01) smaller after S-ECC compared with L-ECC. The second bout resulted in significantly (P < 0.01) reduced changes in all measures compared with the first bout in the subjects who performed L-ECC on both occasions. The subjects who performed S-ECC in the first bout displayed significantly smaller changes after L-ECC than those seen after L-ECC alone, with the degree of attenuation being around 50-70%.

Conclusion: Contrary to the hypothesis, S-ECC provided partial but effective protection against L-ECC. This result suggests adaptations associated with the repeated bout effect were also produced after S-ECC, but the degree of adaptations was not as strong as that by L-ECC. Eccentric exercise at a short extension range can be used as a strategy to present severe muscle damage.

MeSH terms

  • Adolescent
  • Adult
  • Anthropometry
  • Arm / anatomy & histology
  • Aspartate Aminotransferases / blood
  • Athletic Injuries / prevention & control*
  • Creatine Kinase / blood
  • Elbow Joint / physiopathology
  • Humans
  • Isometric Contraction / physiology
  • Male
  • Muscle, Skeletal / injuries*
  • Muscle, Skeletal / pathology
  • Muscle, Skeletal / physiopathology
  • Pain / physiopathology
  • Physical Education and Training / methods*
  • Range of Motion, Articular / physiology


  • Aspartate Aminotransferases
  • Creatine Kinase