INTRODUCTION: Isolated systolic hypertension (ISH) is very common but difficult to manage with conventional medication. We investigated whether slow breathing training, with and without an inspiratory load, could reduce the resting blood pressure of older well-managed ISH patients.
METHODS: Thirty ISH patients (66 ± 4 yr) were randomized into loaded breathing (six breaths per min, 18 cm H2O), unloaded breathing (six breaths per min, no load), or control (normal breathing) groups. After a 2-wk run-in, loaded and unloaded groups trained at home for 30 min every day for 8 wk. Morning home blood pressure and heart rate were measured daily throughout the study. At the end of training, all participants reverted to normal breathing, and blood pressure and heart rate were recorded for a further 8 wk.
RESULTS: Compared to the pretraining run-in period, systolic blood pressure was reduced by 18 ± 7 and 11 ± 4 mm Hg for loaded and unloaded groups, respectively (P < 0.001), the reduction being significantly larger for the loaded group (P < 0.05) after 8-wk training. There were no changes in the control group. After the end of training, systolic blood pressure remained below pretraining levels for a further 6 wk for the loaded group but for only 2 wk with the unloaded group. There was a small nonsignificant reduction in diastolic blood pressure with training, as there was for heart rate. Pulse pressures were reduced by 11 ± 5 and 5 ± 6 mm Hg for loaded and unloaded groups, respectively (P < 0.01).
CONCLUSION: Slow breathing training, especially with an inspiratory load, is very effective in reducing resting systolic and pulse pressures and could be a valuable adjunct in the management of ISH.
PMID: 27128667 DOI: 10.1249/MSS.0000000000000967

BACKGROUND: Inspiratory and peripheral muscle training improves muscle strength, exercise tolerance, and quality of life in patients with chronic heart failure (HF). However, studies investigating different workloads for these exercise modalities are still lacking.
OBJECTIVE: To examine the effects of low and moderate intensities on muscle strength, functional capacity, and quality of life.
DESIGN: A randomized controlled trial.
METHODS: Thirty-five patients with stable HF (aged >18 years, NYHA II/III, LVEF <40%) were randomized to: non-exercise control group (n = 9), low-intensity training group (LIPRT, n = 13, 15% maximal inspiratory workload, and 0.5 kg of peripheral muscle workload) or moderate-intensity training group (MIPRT, n = 13, 30% maximal inspiratory workload and 50% of one maximum repetition of peripheral muscle workload). The outcomes were: respiratory and peripheral muscle strength, pulmonary function, exercise tolerance by the 6-minute walk test, symptoms based on the NYHA functional class, and quality of life using the Minnesota Living with Heart Failure Questionnaire.
RESULTS: All groups showed similar quality-of-life improvements. Low and moderate intensities training programs improved inspiratory muscle strength, peripheral muscle strength, and walking distance. However, only moderate intensity improved expiratory muscle strength and NYHA functional class in HF patients.
CONCLUSIONS: The low-intensity inspiratory and peripheral resistance muscle training improved inspiratory and peripheral muscle strength and walking distance, demonstrating that LIPRT is an efficient rehabilitation method for debilitated HF patients. In addition, the moderate-intensity resistance training also improved expiratory muscle strength and NYHA functional class in HF patients.
KEYWORDS: Cardiac rehabilitation; Functional capacity; Heart failure; Resistance exercise; Respiratory muscles
PMID: 28255812 DOI: 10.1007/s00392-017-1089-y

This case study describes the support given to a British elite athlete in the build up to the 2004 Athens Olympic Games. The athlete had complained of breathing symptoms during high intensity training that led to a reduction in performance and premature cessation of training. Following a negative eucapnic voluntary hyperpnoea challenge and observation during high intensity exercise, the athlete was diagnosed with inspiratory stridor. Inspiratory muscle training (IMT) was implemented to attenuate the inspiratory stridor. Following an 11-week IMT programme, the athlete had a 31% increase in mouth inspiratory pressure and a reduction in recovery between high intensity sprints. The athlete reported a precipitous fall in symptoms and was able to complete high intensity training without symptoms. This case shows that IMT is a suitable cost-effective intervention for athletes who present with inspiratory stridor.
PMID: 17483141 PMCID: PMC2465184 DOI: 10.1136/bjsm.2006.033654

INTRODUCTION: The aim of this pilot study was to assess the effect of pre-operative inspiratory muscle training (IMT) on respiratory variables in patients undergoing major abdominal surgery.
PATIENTS AND METHODS: Respiratory muscle strength (maximum inspiratory [MIP] and expiratory [MEP] mouth pressure) and pulmonary functions were measured at least 2 weeks before surgery in 80 patients awaiting major abdominal surgery. Patients were then allocated randomly to one of four groups (Group A, control; Group B, deep breathing exercises; Group C, incentive spirometry; Group D, specific IMT). Patients in groups B, C and D were asked to train twice daily, each session lasting 15 min, for at least 2 weeks up to the day before surgery. Outcome measurements were made immediately pre-operatively and postoperatively.
RESULTS: In groups A, B and C, MIP did not increase from baseline to pre-operative assessments. In group D, MIP increased from 51.5 cmH(2)O (median) pre-training to 68.5 cmH(2)O (median) post-training pre-operatively (P < 0.01). Postoperatively, groups A, B and C showed a fall in MIP from baseline (P < 0.01, P < 0.01) and P = 0.06, respectively). No such significant reduction in postoperative MIP was seen in group D (P = 0.36).
CONCLUSIONS: Pre-operative specific IMT improves MIP pre-operatively and preserves it postoperatively. Further studies are required to establish if this is associated with reduced pulmonary complications.
PMID: 20663275 PMCID: PMC3229384 DOI: 10.1308/003588410X12771863936648

PURPOSE: We tested the acute responses to differing pressure threshold inspiratory loading intensities in well-trained rowers. The purpose of this study was to evaluate 1) how the magnitude of inspiratory pressure threshold loading influences repetition maximum (RM), tidal volume (VT), and external work undertaken by the inspiratory muscle; and 2) whether the inspiratory muscle metaboreflex is activated during acute inspiratory pressure threshold loading.
METHODS: Eight males participated in seven trials. Baseline measurements of maximal inspiratory pressure (PImax), resting tidal volume (VT), and forced vital capacity (FVC) were made. During the remaining sessions, participants undertook a series of resistive inspiratory breathing tasks at loads corresponding to 50%, 60%, 70%, 80%, and 90% of PImax using a pressure threshold inspiratory muscle trainer. The number of repetitions completed at each load, VT, heart rate (fc), and measures of arterial blood pressure was assessed continuously during each trial.
RESULTS: A standardized cutoff of 10% FVC was used to define the RM, which decreased as loading intensity increased (P < 0.05). This response was nonlinear, with an abrupt decrease in RM occurring at loads > or =70% of PImax. The most commonly used inspiratory muscle training regimen of 30RM corresponded to 62.5% +/- 4.6% of PImax and also resulted in the highest external work output. Tidal volume (VT) decreased significantly over time at 60%, 70%, and 80% of PImax (P < 0.05), as did the amount of external work completed (P<0.05).
CONCLUSIONS: Although all loads elicited a sustained increase in fc, only the 60% load elicited a sustained rise in mean arterial blood pressure (P = 0.016), diastolic blood pressure (P = 0.015), and systolic blood pressure (P = 0.002), providing evidence for a metaboreflex response at this load.
PMID: 20142783 DOI: 10.1249/MSS.0b013e3181d435cf