Impaired exercise ventilatory mechanics with the self-contained breathing apparatus are improved with heliox

@article{Butcher2007ImpairedEV,
  title={Impaired exercise ventilatory mechanics with the self-contained breathing apparatus are improved with heliox},
  author={Scott J. Butcher and Richard L. Jones and Jonathan R. Mayne and Timothy C. Hartley and Stewart R. Petersen},
  journal={European Journal of Applied Physiology},
  year={2007},
  volume={101},
  pages={659-669}
}
The effect of the self-contained breathing apparatus (SCBA) with compressed air (BA-A) on ventilatory mechanics, work of breathing (WOB), pulmonary function, and respiratory muscle fatigue, was compared with that of a low resistance breathing valve (LRV). Further, the effect of unloading the respiratory muscles with heliox with the SCBA (BA-H) was compared with BA-A and LRV. Twelve men completed three randomized exercise trials on separate days, each consisting of three 10 min bouts of stepping… 

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