Oxygen uptake kinetics and maximal aerobic power are unaffected by inspiratory muscle training in healthy subjects where time to exhaustion is extended

Abstract

The aim of this study was to determine whether 4 weeks of inspiratory muscle training (IMT) would be accompanied by alteration in cardiopulmonary fitness as assessed through moderate intensity oxygen uptake (V(.)O(2)) kinetics and maximal aerobic power (V(.)O(2max)). Eighteen healthy males agreed to participate in the study [training group (Tra) n=10, control group (Con) n=8]. Measurements of spirometry and maximal static inspiratory mouth pressure ( PI(max)) were taken pre- and post-training in addition to: (1) an incremental test to volitional exhaustion, (2) three square-wave transitions from walking to running at a moderate intensity (80% ventilatory threshold) and (3) a maximal aerobic constant-load running test to volitional fatigue for the determination of time to exhaustion ( T(lim)). Training was performed using an inspiratory muscle trainer (Powerbreathe). There were no significant differences in spirometry either between the two groups or when comparing the post- to pre-training results within each group. Mean PI(max) increased significantly in Tra ( P<0.01) and showed a trend for improvement ( P<0.08) in Con. Post-training T(lim) was significantly extended in both Tra [232.4 (22.8) s and 242.8 (20.1) s] ( P<0.01) and Con [224.5 (19.6) and 233.5 (12.7) s] ( P<0.05). Post-training T(lim) was significantly extended in Tra compared to Con ( P<0.05). In conclusion, the most plausible explanation for the stability in V(.)O(2) kinetics and V(.)O(2max) following IMT is that it is due to insufficient whole-body stress to elicit either central or peripheral cardiopulmonary adaptation. The extension of post-training T(lim) suggests that IMT might be useful as a stratagem for producing greater volumes of endurance work at high ventilatory loads, which in turn could improve cardiopulmonary fitness.

Does Inspiratory Muscle Trainer Have an Effect on Diaphragmatic Excursion in Hemodialytic Patients?

“…Also the results of this study coincided with the results achieved by Edwards and Cooke,2008 17 who concluded that the inspiratory muscle training device had a significant effect on maximum inspiratory pressure in patients underwent pulmonary lobectomy.…”

Ventilation and Respiratory Mechanics

“…In the case of constant-load exercise tests sustained to the limit of tolerance, the improvements are larger, typically greater than 30% for tests lasting 13 to 20 min (50,180). For higher intensity, shorter duration tests, the improvements are correspondingly smaller, about 4% to 13% for tests lasting 3 to 4 min (50,141).…”

A Comparison between Two Types of Resistive Inspiratory Muscle Training Devices in Normal Subjects in Regards to Pulmonary Functions

“…As Ray, Pendergast, and Lundgren [30] proved that the resistance respiratory muscle training on nine males divers for four weeks (30 min per day, 5 days per week) improved the MVV significantly. In contrast, Edwards and Cooke [31] stated that there was no change in MVV parameter on 18 males between both POWERbreath group (PG=10), the control group (CG=8) and even within the group itself. This could be referred to the low load used in their study, which was only 15% of the MIP.…”