Short-duration fatigue alters neuromuscular coordination of trunk musculature: implications for injury

The aim of this investigation was to determine the effect of muscle fatigue, produced by two different fatigue protocols, on the coordination of trunk and thigh muscles during the performance of a manual-handling task (e.g. a weighted stoop lift). The two fatigue protocols were designed to produce either (a) a non-specific widespread fatigue of trunk and limb muscles (e.g. rowing fatigue protocol), or (b) a specific fatigue of the trunk extensor musculature (e.g. back extension fatigue protocol). Specifically, we wished to determine whether the coordination of trunk muscles during a stoop lift was compromised more, or less, by either of these two fatigue protocols. Ten male subjects (20–24 years) were tested utilising an electromyographic technique which collected electromyograms from trunk flexor and extensor muscles, as well as the Hamstring muscle group, during a pre- and a post-fatigue performance of a weighted stoop lift. The results showed that the back extension fatigue protocol, but not the rowing fatigue protocol, produced significant ( p