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 .
Length-specific impairment of skeletal muscle contractile function after eccentric muscle actions in man.
1 . The effects of maximum voluntary eccentric muscle actions on forearm flexor strength were studied at three different elbow joint angles ( 0.87 , 1.57 and 2.79 rad ) to examine whether subsequent impairment of contractile function is muscle length-specific . 2 . A bout of 70 maximum voluntary eccentric muscle actions performed with the forearm flexors elicited delayed muscle soreness , efflux of creatine kinase into the blood , loss of elbow joint range of motion and a prolonged decline in maximum voluntary isometric contraction torque at the three elbow angles monitored ( P < 0.01 ) in 30 subjects . 3 . The relative decline in maximum voluntary isometric contraction torque after eccentric exercise differed between elbow angles ( P < 0.01 ) . The greatest decline in strength relative to baseline was observed at the most acute elbow angle of 0.87 rad , followed by 1.57 and 2.79 rad respectively . Superimposed electrical stimulation in a subgroup of eight subjects did not increase the torque elicited by the forearm flexors during maximum voluntary contraction tests at the most acute elbow angle ( 0.87 rad ) at any time-point after eccentric exercise , suggesting the disproportionate loss of strength at short muscle length was not due to the inhibitory effects of muscle soreness . 4 . Measures of arm circumference and ability to fully flex the elbow ( in the same subgroup of eight subjects ) suggested the greater decline in strength at the acute elbow angle was not due to the possible confounding influences of muscle swelling and /or impaired muscle shortening ability on strength measurements at short muscle length . 5 . These data suggest a shift in the forearm flexor length-tension relationship could account for the disparate decline in strength between elbow angles after eccentric exercise . The disproportionate loss of strength at short muscle length suggests that eccentric exercise evoked a subtle increase in muscle length , perhaps attributable to the cumulative effects of regions of lengthened sarcomeres and /or series elastic elements
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 .