Figure 2.
Training device description and intervention designs of published high-resistance inspiratory muscle strength training studies. Device type indicates whether the same absolute level of resistance is applied across an entire inspiration (constant) or whether absolute resistance declines during inspiration with decreasing inspiratory pressure production (tapered loading). Inspiratory resistance describes the protocol training intensity as a relative percentage of subjects’ maximal inspiratory pressure production. ML/O = midlife/older. OSA = obstructive sleep apnea. PIMAX = maximal inspiratory pressure.