Inspiratory Muscle Training Included in Therapeutic and Training Regimens for Middle-Distance Runners

<b>Objectives</b>: The aim of this study was to evaluate the effectiveness of respiratory muscle training in runners in relation to gender and trainers (PowerBreathe and Threshold). <b>Methods</b>: This study comprised 32 athletes training in middle-distance running at a high sports level. The subjects were divided into groups depending on the applied breathing training (IMT): group IMT on the PowerBreath, group IMT on the Threshold, and the control group labeled sham-IMT. The following tests were performed on each athlete: spirometry, maximal inspiratory pressure, expiratory pressure, and physical performance. <b>Results</b>: A significant increase in the levels of the parameters VO₂/kg, PEF, PI_max, and PE_max, as well as a decrease in lactic acid levels and an increase in lactate threshold in both sexes, were observed as a result of the training on the PowerBreathe device. There were no significant differences in the levels of the parameters VO₂/kg, PEF, PI_max, lactic acid, and lactate threshold in either sex after Threshold training. A significant increase in PE_max was found in the Threshold device training group. <b>Conclusions</b>: Most of the assessed parameters of physical fitness and lung ventilation function, along with the respiratory muscle strength of women and men running middle distances, increased significantly after the use of IMT on PowerBreathe, and these results were maintained in the third stud, in contrast to the use of IMT on Threshold, with which there was no significant improvement.