Conclusion Overall , our findings do not support the presence of a secondary loss of strength following an acute muscle injury , and strongly suggest that strength , on average , recovers steadily over the first 3 days post-injury
Background An immediate loss of strength follows virtually all types of muscle injury but there is debate whether the initial strength loss is maximal or if a secondary loss of strength occurs during the first 3 days post-injury .
Objective The objective of this analysis was to conduct a systematic review and meta- analysis of the research literature to determine if a secondary loss of strength occurs after an injurious initiating event .
Attenuation of contraction-induced skeletal muscle injury by bromelain.
The proteolytic enzyme , bromelain , reportedly has therapeutic effects in the treatment of inflammation and soft tissue injuries . We tested the hypothesis that bromelain attenuates skeletal muscle injury induced by lengthening contractions . The left extensor digitorum longus ( EDL ) muscle of anesthetized hamsters was injured using a motorized foot pedal which repeatedly flexed/extended the foot through a range of 125 degrees . The EDL muscle was electrically stimulated for 400 ms during plantarflexion . Animals were assigned r and omly to either a 0-d group ( evaluated 3-h post-injury ) or to untreated ( UT ) or bromelain-treated ( T ) groups , evaluated 3 , 7 , or 14 d post-injury . Following injury , T received 5 mg.kg-1 b.w . of bromelain , twice daily . Maximum isometric tetanic force ( Po ) was measured in vitro , then muscles were fixed , sectioned , and examined for evidence of fiber damage . The Po of injured muscles from T were higher than Po of injured muscles from UT at 3 ( 18.7 + /- 0.4 vs 16.5 + /- N.cm-2 and 14 d ( 20.5 + /- 0.6 vs 18.2 + /- 0.6 N.cm-2 ) ( P less than 0.05 ) , but not 7 d ( 19.5 + /-0.7 vs 17.7 + /- 0.8 N.cm-2 ) . The Po of UT injured muscles were significantly lower than Po of contralateral control muscles at all time periods . Po of injured muscles from T were lower than Po from control muscles at 3 and 7 d ( P less than 0.05 ) , but not 14 d. The number of intact fibers of 3-d UT injured muscles was lower than the number of intact fibers in control muscles ( P less than 0.05 ) . ( ABSTRACT TRUNCATED AT 250 WORDS
Conclusion Overall , our findings do not support the presence of a secondary loss of strength following an acute muscle injury , and strongly suggest that strength , on average , recovers steadily over the first 3 days post-injury
Background An immediate loss of strength follows virtually all types of muscle injury but there is debate whether the initial strength loss is maximal or if a secondary loss of strength occurs during the first 3 days post-injury .
Objective The objective of this analysis was to conduct a systematic review and meta- analysis of the research literature to determine if a secondary loss of strength occurs after an injurious initiating event .