Most sport scientists still do not consider breathing to be a limiting factor for exercise performance. However, the past decade has seen evidence emerge showing unequivocally that breathing not only limits exercise performance, but that removal of this limitation improves performance. This review will describe the mechanisms by which respiratory muscle work limits exercise performance, as well as the evidence that specific training of the respiratory pump muscles improves performance in the context of both endurance and repeated sprint sports. Finally, the mechanisms underlying this ergogenic effect will be considered, as well as their implications for the practical application of respiratory muscle training. [ J Exerc Sci Fit • Vol 7 • No 2 (Suppl) • S18- S27 • 2009
