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 .
Diurnal variation, response to eccentric exercise, and association of inflammatory mediators with muscle damage variables.
This investigation determined whether inflammatory mediators 1 ) have diurnal variations , 2 ) respond to high-force eccentric exercise , and 3 ) associate with markers of muscle damage after high-force eccentric exercise .  College-aged men and women ( n = 51 ) completed exercise ( 3 x 15 maximal eccentric elbow flexor actions using 1 arm ) and control conditions in r and om order . Blood was collected preexercise and 4 , 8 , 12 , 24 , 48 , and 96 h postexercise . Additional measures included maximal isometric force and midbiceps arm circumference ( to detect swelling ) . Serum and plasma were analyzed for soluble tumor necrosis factor receptor-1 ( sTNFR1 ) , IL-6 , C-reactive protein , cortisol , and creatine kinase ( CK ) activity . Relative to the 7:00 AM point in the control condition , diurnal decreases were measured at 12:00 PM and 4:00 PM for IL-6 and at 12:00 PM , 4:00 PM , and 8:00 PM for sTNFR1 and cortisol . sTNFR1 , IL-6 , CK , swelling , and soreness were higher in the exercise compared with the control condition . The largest of the inflammatory mediator responses was measured for IL-6 8 h postexercise in the exercise ( 3.00 + /- 3.59 pg/ml ) relative to the control condition ( 1.15 + /- 0.99 pg/ml ) . The IL-6 response ( time-matched exercise -- control concentration ) at 8 h associated ( r > 0.282 ) with muscle soreness at 24 and 96 h , and the cortisol response at 8 h associated ( r > 0.285 ) with swelling at 8 , 24 , and 96 h. Thus soreness and swelling , but not CK and strength loss , had a low association with the inflammatory response following eccentric exercise
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 .