The misuse of respiratory resistive loading during aerobic exercises: revisiting mechanisms of "standalone" inspiratory muscle training.

Systematic reviews and meta-analyses support the benefits of inspiratory muscle training (IMT) for sports and clinical populations. A typical application of "standalone" IMT intervention consists of breathing against an inspiratory load (IRL), twice daily, for 5-7 days/wk, for 4-12 wk. However, the application of IRL during aerobic exercise is often seen in a training routine of sports and rehabilitation centers with no evidence-based guide. In this Perspective, we will revisit putative mechanisms underlying the established benefits of "standalone" IMT to support our contention that IMT need not and should not be used during aerobic exercise.