Does training of respiratory muscles affect exercise performance in healthy subjects?

Ventilatory demand during exercise is met by increased volume and airflow. They require higher negative pleural pressure (Pes) which peak ranges from 49% to 90% of maximal pressure generating capacity (Pcap) of the respiratory muscles during both incremental maximal and endurance exercise. In these conditions the diaphragm progressively reduces over time its relative pressure contribution (Pdi) to total inspiratory muscle output (Pdi/Pes). Studies employing non-volitional methods have demonstrated that high-intensity whole body exercise endurance (485% VO2max) induces global respiratory muscle fatigue. In this context, the functional significance of improved respiratory muscle function with respiratory muscle training (RMT) would presumably be to prevent or delay the diaphragm fatigue that is known to occur during sustained high-intensity exercise. Competition for