Effect of semi-rigid lumbosacral orthosis use on oxygen consumption during repetitive stoop and squat lifting.

The use of back belts in industry has increased despite the lack of scientific evidence supporting their efficacy. The purpose of this study was to investigate the effect of a semi-rigid lumbosacral orthosis (SRLSO) on oxygen consumption during 6-min submaximal repetitive lifting bouts of 10 kg at a lifting frequency of 20 repetitions min-1. Fifteen healthy subjects (13 men, two women) participated in this study. Each subject performed squat and stoop lifting with and without an SRLSO for a total of four lifting bouts. Lifting bouts were performed in random order. Oxygen consumption during the final minute of each lifting bout was used for analysis. A two-way analysis of variance with repeated measures was used to analyse the effects of lift and belt conditions. The stoop and squat methods were significantly different, with the squat lift requiring 23% more oxygen on average than the stoop lift for equal bouts of work. No significant difference was found between the belt and no belt condition within the same lifting technique and no interaction was present. These data suggest that an SRLSO does not passively assist the paravertebral muscles (PVM) in stabilizing the spine during submaximal lifting bouts.