Hamstring strain injuries and eccentric strength training
Previous history of hamstring strain injury (HSI) is identified as a main risk factor for recurrent injuries. Neuromuscular inhibition has been found to be associated with HSIs and it has been blamed for the elevated risk of reinjuries in athletes with previous HSIs. The aim of this study was to compare the increase in hamstring eccentric strength during preseason training amongst footballers with or without a history of HIS.
17 footballers with a history of unilateral HSI and 82 controls participated in the study. The eccentric strength of the hamstrings was measured at the start and the end of the preseason training utilizing the Nordic hamstring exercise.
The previously injured group presented with significantly less improvement in eccentric hamstring strength compared to the healthy controls. The suppressed response to eccentric strength gains was not displayed unilaterally - to the limb with a history of HSI - but bilaterally to both legs. Neuromuscular inhibition might limit the adaptive capacity of a previously injured athlete, however, whether this is “chicken or the egg” remains to be elucidated.
> From: Opar et al., Am J Sports Med (2014) (Epub ahead of print). All rights reserved to The Author(s). Click here for the Pubmed summary.