Daily inspiratory muscle training lowers blood pressure and vascular resistance in healthy men and women

Abstract

Previous work has shown that inspiratory muscle training (IMT) lowers blood pressure after a mere 6 weeks, identifying IMT as a potential therapeutic intervention to prevent or treat hypertension. Here, we explore the effects of IMT on respiratory muscle strength and select cardiovascular parameters in recreationally active men and women. Subjects were randomly assigned to IMT (n = 12, 75% maximal inspiratory pressure) or sham training (n = 13, 15% maximal inspiratory pressure) groups and underwent a 6-week intervention comprising 30 breaths day , 5 days week . Pre- and post-training measures included maximal inspiratory pressure and resting measures of blood pressure, cardiac output, heart rate, spontaneous cardiac baroreflex sensitivity and systemic vascular resistance. We evaluated psychological and sleep status via administration of the Cohen-Hoberman inventory of physical symptoms and the Epworth sleepiness scale. Male and female subjects in the IMT group showed declines in systolic/diastolic blood pressures (-4.3/-3.9 mmHg, P < 0.025) and systemic vascular resistance (-3.5 mmHg min l , P = 0.008) at week 6. There was no effect of IMT on cardiac output (P = 0.722), heart rate (P = 0.795) or spontaneous cardiac baroreflex sensitivity (P = 0.776). The IMT subjects also reported fewer stress-related symptoms (pre- versus post-training, 12.5 ± 8.5 versus 7.2 ± 9.7, P = 0.025). Based on these results, we suggest that a short course of IMT confers significant respiratory and cardiovascular improvements and parallel (modest) psychological benefits in healthy men and women.

A Transfer Entropy Approach for the Assessment of the Impact of Inspiratory Muscle Training on the Cardiorespiratory Coupling of Amateur Cyclists

“…It is worth noting that at REST the MIP60 training was able to evoke a significant bradycardia in presence of an unvaried SAP. This finding is in contrast with some studies suggesting that IMT of moderate intensity could lower arterial pressure while leaving unmodified HP values in both normotensive (Vranish and Bailey, 2015;DeLucia et al, 2018) and hypertensive (Ferreira et al, 2013) subjects. Even the improvement of arterial pressure regulation, reported in subjects with orthostatic hypotension such as those after spinal cord injury (Aslan et al, 2016), it is not evident in our study given that the baroreflex control is not affected by IMT.…”

“…Conversely, no PRE-POST variation of BRS was observed and the usual trend of baroreflex markers with STAND was detected after MIP60 training. The lack of influences on the baroreflex regulation is in agreement with data derived during a session of breathing through an inspiratory resistance of small value (Convertino et al, 2004a) and with the long-term effects of an IMT training of moderate intensity (DeLucia et al, 2018). We suggest that the post-training changes of CRCS detected by TE RM→HP|SAP during STAND in MIP60 group are due to mechanisms unrelated to baroreflex.…”

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

“…One possibility is the use of respiratory muscle training (RMT) (Illi et al, 2012), in which intensive respiratory maneuvers are performed while no activity is required from the upper or lower limbs. Large decreases in systolic (SBP) and diastolic (DBP) blood pressure in normotensive adults were found after 6-weeks of strength-like RMT, but only when large pressures were used (Vranish and Bailey, 2015;DeLucia et al, 2018), a finding which has not been supported by others (Witt et al, 2007), including in more frail populations (Chiappa et al, 2008). Much less is known about potential changes on arterial stiffness brought by RMT, with a single investigation suggesting increased arterial compliance following RMT, without measuring PWV (DeLucia et al, 2018).…”

“…Large decreases in systolic (SBP) and diastolic (DBP) blood pressure in normotensive adults were found after 6-weeks of strength-like RMT, but only when large pressures were used (Vranish and Bailey, 2015;DeLucia et al, 2018), a finding which has not been supported by others (Witt et al, 2007), including in more frail populations (Chiappa et al, 2008). Much less is known about potential changes on arterial stiffness brought by RMT, with a single investigation suggesting increased arterial compliance following RMT, without measuring PWV (DeLucia et al, 2018). This is a topic that needs further clarification, as for example endurance and resistance training have been shown to decrease and increase arterial stiffness respectively (Collier et al, 2008), the latter possibly due to the pressure swings resulting from Valsalva maneuvers during intense muscle contractions (Heffernan et al, 2007b).…”

Additional Improvement of Respiratory Technique on Vascular Function in Hypertensive Postmenopausal Women Following Yoga or Stretching Video Classes: The YOGINI Study

“…Regarding endothelial function, several studies have demonstrated the effectiveness of yoga (Hunter et al, 2017 , 2018 ). However, the impact of slow breathing on endothelial and vascular function has not yet been demonstrated (Limberg et al, 2013 ; DeLucia et al, 2018 ). Multiple components of yoga such as physical poses ( asanas ), respiratory exercises ( pranayamas ), meditation, and devotional and lifestyle aspects have never been analyzed separately in order to assess specific benefits (Hartley et al, 2014 ).…”