The aim of this review was to reexamine the specificity of exercises intended to condition the lumbar extensor musculature (ie, lumbar erector spinae and multifidus). The authors conducted a review of studies examining effects of exercises designed to condition the lumbar extensors. Included were studies that looked at the acute activation and chronic adaptation of the lumbar extensor musculature in response to benches and roman chair trunk extensions, free weights exercises (ie, deadlifts, squats, good-mornings, etc), floor and stability ball exercise (ie, trunk extensions, bridging, four-point kneeling, etc) and resistance machines (ie, those with and without pelvic restraints). Evidence indicates that the reviewed exercises designed to condition the lumbar extensors all may result in substantial activation of this musculature during their performance. However, examination of training studies shows that for benches and roman chair trunk extensions, free weights exercises, floor and stability ball exercise and resistance machines without appropriate pelvic restraints, evidence suggests that they may be less effective for inducing chronic adaptations in the lumbar extensors as a result of their performance. Contrastingly, resistance machines that employ appropriate pelvic restraint to isolate lumbar extension are better evidenced to confer specific adaptations to the lumbar extensors. Many exercise approaches have been designed with the intention of conditioning the lumbar extensors. Those examined seem to activate the lumbar extensors; however, the specificity of a considerable number of these exercises for producing chronic adaptations may be questionable, possibly because of the compound nature of them allowing involvement of other musculature such as the hip extensors.
It was concluded that quite a few of the reviewed exercises offer potential to condition the lumbar extensors, however, isolation of lumbar extension through appropriate pelvic restraint seems to be significant in optimising specific adaptations in the lumbar extensors.