AUTHOR=Beltrami Fernando G. , Mzee David , Spengler Christina M. 

TITLE=No Evidence That Hyperpnea-Based Respiratory Muscle Training Affects Indexes of Cardiovascular Health in Young Healthy Adults

JOURNAL=Frontiers in Physiology

VOLUME=11

YEAR=2020

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2020.530218

DOI=10.3389/fphys.2020.530218

ISSN=1664-042X

ABSTRACT=<sec><title>Introduction</title><p>The chronic effects of respiratory muscle training (RMT) on the cardiovascular system remain unclear. This investigation tested to which degree a single sessions of RMT with or without added vibration, which could enhance peripheral blood flow and vascular response, or a 4-week RMT program could result in changes in pulse wave velocity (PWV), blood pressure (systolic, SBP; diastolic, DBP) and other markers of cardiovascular health.</p></sec><sec><title>Methods</title><p>Sixteen young and healthy participants (8 m/8f) performed 15 min of either continuous normocapnic hyperpnea (RMET), sprint-interval-type hyperpnea (RMSIT) or a control session (quiet sitting). Sessions were performed once with and once without passive vibration of the lower limbs. To assess training-induced adaptations, thirty-four young and healthy participants (17 m/17f) were measured before and after 4 weeks (three weekly sessions) of RMET (<italic>n</italic> = 13, 30-min sessions of normocapnic hyperpnea), RMSIT [<italic>n</italic> = 11, 6 × 1 min (1 min break) normocapnic hyperpnea with added resistance] or placebo (<italic>n</italic> = 10).</p></sec><sec><title>Results</title><p>SBP was elevated from baseline at 5 min after each RMT session, but returned to baseline levels after 15 min, whereas DBP was unchanged from baseline following RMT. Carotid-femoral PWV (PWV<sub>CF</sub>) was elevated at 5 and 15 min after RMT compared to baseline (main effect of time, <italic>P</italic> = 0.001), whereas no changes were seen for carotid-radial PWV (PWV<sub>CR</sub>) or the PWV<sub>CF</sub>/PWV<sub>C</sub><sub>R</sub> ratio. Vibration had no effects in any of the interventions. Following the 4-week training period, no differences from the placebo group were seen for SBP (<italic>P</italic> = 0.686), DBP (<italic>P</italic> = 0.233), PWV<sub>CF</sub> (<italic>P</italic> = 0.844), PWV<sub>CR</sub> (<italic>P</italic> = 0.815) or the PWV<sub>CF</sub>/PWV<sub>CR</sub> ratio (<italic>P</italic> = 0.389).</p></sec><sec><title>Discussion/Conclusion</title><p>Although 15 min of RMT sessions elicited transient increases in PWV<sub>CF</sub> and SBP, no changes were detected following 4 weeks of either RMET or RMSIT. Adding passive vibration of the lower limbs during RMT sessions did not provide additional value to the session with regards to vascular responses.</p></sec>