Effects of aerobic and inspiratory strength muscle training on exaggerated blood pressure response during exercise in hypertensive patients

This study evaluated the effectiveness of inspiratory muscle strength training (IMST) as a time-efficient alternative to widely recommended aerobic exercise (AE) for reducing and maintaining blood pressure in hypertensive patients. Twenty-eight hypertensive patients (aged 61 ± 7 years) were randomly assigned to IMST (n = 14) and AE (n = 14) groups. The IMST performed 30 breaths/session at 75% of maximal inspiratory pressure (PImax), totaling about 8 minutes, 5 days/week. The AE group exercised at 70% of heart rate reserve for 30 minutes/session, 5 days/week. Both supervised interventions lasted 8 weeks, followed by a 4-week detraining period. Brachial and central systolic blood pressure (SBP) were taken at baseline, 8-week post-intervention, and post-detraining. The mean (standard deviation) change in brachial SBP from baseline to 8 week post-intervention significantly decreased in both the IMST group [-9.1 (12.1) mmHg, P = 0.01] and the AE group [-6.2 (7.2) mmHg, P = 0.01], with no significant difference between groups (P = 0.46). Central SBP also significantly reduced in the IMST group [-9.0 (11.9) mmHg, P = 0.01] and in the AE group [-5.7 (6.2) mmHg, P = 0.01], with no significant difference between groups (P = 0.37). However, the IMST group did not show significant persistence in SBP reduction, whereas the AE group did. Both IMST and AE effectively reduced brachial and central BP after 8-week interventions in hypertensive patients. While IMST presents a time-efficient adjunctive option to AE, its long-term effectiveness remains uncertain.

To assess the association between an exaggerated exercise systolic blood pressure response and the occurrence of left ventricular hypertrophy in healthy, normotensive individuals. Cross-sectional survey using M-mode echocardiography to measure left ventricular mass and to detect left ventricular hypertrophy. The Framingham Heart Study. Eight-hundred sixty men and 1118 women were studied who were free of cardiovascular or pulmonary disease, who were not taking any antihypertensive or cardiovascular medications, and who successfully achieved at least 90% of their age-predicted maximum heart rate during a monitored exercise treadmill test. All subjects had normal baseline and exercise electrocardiograms. Men with a peak exercise systolic blood pressure of 210 or more and women with a peak exercise systolic blood pressure of 190 or more were considered to have an "exaggerated" blood pressure response; 122 men and 67 women met these criteria. Subjects with an exaggerated exercise systolic blood pressure response had 10% higher left ventricular mass than those with a normal exercise systolic blood pressure response (in men: 115 +/- 25 compared with 105 +/- 24 g/m, P less than 0.001; in women: 86 +/- 22 compared with 73 +/- 16 g/m, P less than 0.001); they also had a higher prevalence of left ventricular hypertrophy (in men: odds ratio, 1.34, 95% CI, 1.00 to 1.80; in women: odds ratio, 2.12, CI, 1.48 to 3.03). After adjusting for age, resting systolic blood pressure, and body mass index, however, subjects with an exaggerated exercise systolic blood pressure response had only 5% higher left ventricular mass (in men: 111 +/- 2.1 compared with 106 +/- 0.8 g/m, P = 0.02; in women: 80 +/- 1.8 compared with 74 +/- 0.4 g/m, P = 0.002), and they no longer had a statistically increased prevalence of left ventricular hypertrophy (in men: odds ratio, 1.21, CI, 0.87 to 1.67; in women: odds ratio, 1.30, CI, 0.84 to 2.01). The apparent relation between exercise systolic blood pressure response and left ventricular mass is confounded by age, resting systolic blood pressure, and body mass; the degree of confounding is such that the biologic significance of this relationship should be questioned.

BackgroundHigh‐resistance inspiratory muscle strength training (IMST) is a novel, time‐efficient physical training modality.Methods and ResultsWe performed a double‐blind, randomized, sham‐controlled trial to investigate whether 6 weeks of IMST (30 breaths/day, 6 days/week) improves blood pressure, endothelial function, and arterial stiffness in midlife/older adults (aged 50–79 years) with systolic blood pressure ≥120 mm Hg, while also investigating potential mechanisms and long‐lasting effects. Thirty‐six participants completed high‐resistance IMST (75% maximal inspiratory pressure, n=18) or low‐resistance sham training (15% maximal inspiratory pressure, n=18). IMST was safe, well tolerated, and had excellent adherence (≈95% of training sessions completed). Casual systolic blood pressure decreased from 135±2 mm Hg to 126±3 mm Hg (P<0.01) with IMST, which was ≈75% sustained 6 weeks after IMST (P<0.01), whereas IMST modestly decreased casual diastolic blood pressure (79±2 mm Hg to 77±2 mm Hg, P=0.03); blood pressure was unaffected by sham training (all P>0.05). Twenty‐four hour systolic blood pressure was lower after IMST versus sham training (P=0.01). Brachial artery flow‐mediated dilation improved ≈45% with IMST (P<0.01) but was unchanged with sham training (P=0.73). Human umbilical vein endothelial cells cultured with subject serum sampled after versus before IMST exhibited increased NO bioavailability, greater endothelial NO synthase activation, and lower reactive oxygen species bioactivity (P<0.05). IMST decreased C‐reactive protein (P=0.05) and altered select circulating metabolites (targeted plasma metabolomics) associated with cardiovascular function. Neither IMST nor sham training influenced arterial stiffness (P>0.05).ConclusionsHigh‐resistance IMST is a safe, highly adherable lifestyle intervention for improving blood pressure and endothelial function in midlife/older adults with above‐normal initial systolic blood pressure.RegistrationURL: https://www.clinicaltrials.gov; Unique identifier: NCT03266510.

Above-normal blood pressure (BP) is a primary risk factor for cardiovascular diseases. In a retrospective analysis of five pilot trials, we assessed the BP-lowering effects of high-resistance inspiratory muscle strength training (IMST) in adults aged 18-82 years and the impact of IMST on maximal inspiratory pressure (PIMAX), a gauge of inspiratory muscle strength and independent disease risk factor. Participants were randomized to high-resistance IMST (75% PIMAX) or low-resistance sham (15% PIMAX) training (30 breaths/day, 5-7 days/wk, 6 wk). IMST (n = 67) reduced systolic BP (SBP) by 9 ± 6 mmHg (P < 0.01) and diastolic BP (DBP) by 4 ± 4 mmHg (P < 0.01). IMST-related reductions in SBP and DBP emerged by week 2 of training (-4 ± 8 mmHg and -3 ± 6 mmHg; P ≤ 0.01, respectively) and continued across the 6-wk intervention. SBP and DBP were unchanged with sham training (n = 61, all P > 0.05). Select subject characteristics slightly modified the impact of IMST on BP. Greater reductions in SBP were associated with older age (β = -0.07 ± 0.03; P = 0.04) and greater reductions in DBP associated with medication-naïve BP (β = -3 ± 1; P = 0.02) and higher initial DBP (β = -0.12 ± 0.05; P = 0.04). PIMAX increased with high-resistance IMST and low-resistance sham training, with a greater increase from high-resistance IMST (+20 ± 17 vs. +6 ± 14 cmH2O; P < 0.01). Gains in PIMAX had a modest inverse relation with age (β = -0.20 ± 0.09; P = 0.03) and baseline PIMAX (β = -0.15 ± 0.07; P = 0.04) but not to reductions in SBP or DBP. These compiled findings from multiple independent trials provide the strongest evidence to date that high-resistance IMST evokes clinically significant reductions in SBP and DBP, and increases in PIMAX, in adult men and women.NEW & NOTEWORTHY In young-to-older adult men and women, 6 wk of high-resistance inspiratory muscle strength training lowers casual systolic and diastolic blood pressure by 9 mmHg and 4 mmHg, respectively, with initial reductions observed by week 2 of training. Given blood pressure outcomes with the intervention were only slightly altered by subject baseline characteristics (i.e., age, blood pressure medication, and health status), inspiratory muscle strength training is effective in lowering blood pressure in a broad range of adults.

Aging and above normal systolic blood pressure (SBP) are independently and additively associated with decreased cognitive and motor function, which increase the risk of developing dementia and physical disabilities, respectively. Traditional aerobic exercise regimens may reduce the risk of cognitive and physical decline with aging. However, they are associated with relatively poor adherence among older adults, and only modest reductions in SBP (e.g., ≤5mmHg). As such, there is an unmet need for novel exercise modalities with improved adherence and SBP‐lowering effects. High‐intensity inspiratory muscle strength training (IMST) is a time‐efficient (~5 min/day) form of exercise with excellent adherence and strong SBP‐lowering effects in select groups. Whether IMST improves cognitive and motor function and/or lowers SBP in middle‐aged and older adults is unknown. The purpose of this study was to determine if 6‐weeks of IMST improves cognitive and motor function, while lowering SBP in middle‐aged to older adults with above‐normal SBP (≥120 mmHg).MethodsMiddle‐aged and older adults (50–79 years) with above‐normal SBP were recruited. Subjects were randomly allocated to perform 6‐weeks of IMST (30 breaths/day; 6 days/week; 75% maximum inspiratory pressure [PIMAX]) (n=7 age: 68±2, SBP: 137±3 mmHg) or sham (15% PIMAX) training (n=7; age: 67±3, SBP: 134±5 mmHg). Motor and cognitive function was measured at baseline and post‐intervention with the NIH Toolbox cognitive and motor battery of tests and other standardized measurements, including trail making test (TMT) parts A and B.ResultsNeither treatment altered body weight, body composition or blood clinical markers (all p&gt;0.05). 6‐weeks of IMST significantly reduced SBP (−10±2 mmHg, p=0.001) compared with sham training (−4±2 mmHg, p=0.13). Selective domains of fluid cognition, including episodic memory (picture sequence memory test; +11±2 AU, p=0.04) and processing speed (TMT‐A; −6±1 sec, p=0.02) were improved after 6‐weeks of IMST, as was overall fluid cognition (composite score; +7±2 AU, p=0.02). The improvement in episodic memory was inversely related to changes in SBP (R2=0.40, p=0.01). Crystallized cognition (e.g., verbal knowledge) was unchanged with IMST (composite score; +2±2 AU, p=0.37). No domains of cognitive function changed in the sham group (all p&gt;0.05). There was no effect of IMST on any measures of motor function, while gait speed improved slightly in the sham group (+0.22±0.07 m/s; p=0.002).ConclusionsThese data suggest IMST improves processing speed and episodic memory in middle‐aged to older adults, and the improvements may be related to IMST‐induced reductions in SBP.Support or Funding InformationAHA 18POST33990034, T32 DK007135, UL1 TR002535, R25 HL115473This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Exaggerated blood pressure responses (EBPR) during exercise are associated with increased risk of mortality. Due to the prognostic value of EBPR, it is important to evaluate the reliability of criteria used to define this response. PURPOSE: This study assessed the test-retest reliability of two different criteria used to define EBPR: the maximal systolic blood pressure (SBP) and the SBP/METs-slope which is the ratio of the change in SBP to the change in the metabolic equivalents of task (METs). METHODS: Twenty healthy, normotensive adults (8 males: 21±1 years, 12 females: 21±1 years) completed two identical modified Bruce treadmill tests on separate days. Blood pressure was measured using an automated motion-tolerant auscultatory device at rest (i.e., standing on treadmill) and during the last minute of each exercise stage. For each test, maximal SBP was identified, METs were estimated, and the change in these indices (i.e., maximal – rest) were calculated to determine the SBP/METs-slope. Test-retest reliability of the two criteria were assessed using intraclass correlation coefficients (ICC), with an ICC > 0.60 considered reliable. RESULTS: Total exercise time was similar between visits (1000±123 s vs. 1005±128 s, P=0.33). Reliability of the EBPR criteria are presented as (ICC; 95% confident intervals). Maximal SBP (0.45; 0.02-0.74) and SBP/METs-slope (0.29; -0.16-0.64) were not reliable. Participants were then separated based on sex. In males, maximal SBP (0.85; 0.44-0.97) was reliable while the SBP/METs-slope only demonstrated moderate reliability (0.59; -0.13-0.90). In females, both maximal SBP and the SBP/METs-slope were not reliable (ICCs <0.17). Using the criteria of a maximal SBP ≥210 and ≥190 mmHg for males and females respectively, 50% of males and 33% of females had EBPR on both visits. CONCLUSION: Criteria used to define EBPR are only reliable in males. Further investigation is warranted to understand the potential sex effects on the SBP responses to maximal exercise testing.

Type 2 diabetes mellitus (T2DM) is a complex, chronic metabolic disease that is associated with a high prevalence of comorbid conditions. Traditional lifestyle interventions (e.g., diet and exercise) can counter some adverse effects of T2DM; however, participation in these activities is low. High-resistance inspiratory muscle strength training (IMST) is a time-effcient and simple breathing exercise that significantly reduces blood pressure (BP) and improves vascular endothelial function in several nondiabetic populations. Herein, we performed a blinded, randomized, sham-controlled trial to investigate the effects of a 6-week IMST regimen (30 breaths/day, 6 days/week) on glycemic control and insulin sensitivity in adults with T2DM. Currently, we have eight participants (aged 35-71 years, 5 females and 3 males) who have completed either low-resistance sham training (15% maximal inspiratory mouth pressure, n=5) or high-resistance IMST (75% maximal inspiratory mouth pressure, n=3). Our data suggests that fasting plasma glucose and fasting serum insulin did not significantly change by IMST or sham training. Utilizing a homeostatic model assessment of insulin sensitivity to evaluate insulin action, our results indicate no change by either IMST or sham training. IMST revealed a trend towards a reduction in systolic BP (pre: 133.0 ± 4.8 vs. post: 128.8 ± 4.9) and diastolic BP (pre: 84.8 ± 2.7 vs. post: 81.7 ± 3.6). These findings align with prior research indicating improved resting BP, further corroborating previous studies. We performed an exploratory analysis to examine the potential impact of IMST on lipid levels. Interestingly, IMST resulted in a trend towards a reduction in cholesterol (pre: 259.3 ± 29.4 vs. post: 230.3 ± 3.7) and LDL (pre: 153.3 ± 19.7 vs. post: 127.7 ± 8.7). Analysis of the endothelial function data is forthcoming until we have enough individuals to complete those analyses. In conclusion, our results to date are preliminary; however, we expect to see continued improvements in resting BP and cholesterol/LDL with IMST. Moreover, with a higher number of individuals in the study (our goal is to have 12 in each group), we anticipate seeing changes in glycemia or insulin action. Lastly, IMST stands out as a distinctive and time-effective exercise method, addressing adherence challenges while demonstrating enhancements in cardiometabolic health. This could be particularly advantageous for T2DM patients with an increased cardiovascular disease risk. University of Arizona College of Medicine SPARK Grant. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Background: Cardiovascular disease is a major global health concern and prevalence is high in adults with obstructive sleep apnea (OSA). Lowering blood pressure (BP) can greatly reduce cardiovascular disease risk and physical activity is routinely prescribed to achieve this goal. Unfortunately, many adults with OSA suffer from fatigue, daytime sleepiness, and exercise intolerance—due to poor sleep quality and nocturnal hypoxemia—and have difficulty initiating and maintaining an exercise program. High-resistance inspiratory muscle strength training (IMST) is a simple, time-efficient breathing exercise consistently reported to reduce BP in small, selective groups of both healthy and at-risk adults. Herein we present the study protocol for a randomized clinical trial to determine the long-term efficacy of IMST performed regularly for 24 weeks in middle-aged and older adults with OSA. The primary outcome is casual systolic BP. Secondary outcomes are 24-h systolic BP and circulating plasma norepinephrine concentration. Other outcomes include vascular endothelial function (endothelial-dependent and -independent dilation), aortic stiffness, casual and 24-h diastolic BP, and the influence of circulating factors on endothelial cell nitric oxide and reactive oxygen species production. Overall, this trial will establish efficacy of high-resistance IMST for lowering BP and improving cardiovascular health in middle-aged and older adults with OSA.Methods: This is a single-site, double-blind, randomized clinical trial. A minimum of 92 and maximum of 122 male and female adults aged 50–80 years with OSA and above-normal BP will be enrolled. After completion of baseline assessments, subjects will be randomized in a 1:1 ratio to participate in either high-resistance or sham (low-resistance) control IMST, performed at home, 5 min/day, 5 days/week, for 24 weeks. Repeat assessments will be taken after the 24-week intervention, and after 4 and 12 weeks of free living.Discussion: This study is designed to assess the effects of 24 weeks of IMST on BP and vascular function. The results will characterize the extent to which IMST can reduce BP when performed over longer periods (i.e., 6 months) than have been assessed previously. Additionally, this study will help to determine underlying mechanisms driving IMST-induced BP reductions that have been reported previously.Clinical Trial Registration: This trial is registered with ClinicalTrials.gov (Registration Number: NCT04932447; Date of registration June 21, 2021).

Previous work has shown that hypertensive patients that undertake 8 weeks of inspiratory muscle strength training exhibit significant declines in systolic and diastolic blood pressure [Ferreira et al., 2011], and our lab has been able to reproduce these results in a healthy young adult population over a 6 week training period [unpublished data]. The mechanism underlying this change is not known. Here, we compare inspiratory muscle strength training (‐ pressure, + lung volume) against four other training protocols: deep breathing (+ lung volume), Mueller maneuver (‐ pressure), expiratory muscle strength training (+ volume, + pressure), and placebo, to determine which parameter may affect blood pressure. Fifty healthy adult volunteers (ages 18‐30) were randomly assigned to one of the five treatment groups and undertook 5 minutes of supervised training, 5 days a week, over a period of 6 weeks. After 4 weeks, preliminary findings from fifteen men and women show reductions in systolic and diastolic blood pressure for individuals in inspiratory (‐8.0/‐2.3) and expiratory (‐9.6/‐2.1) muscle strength training groups as well as the Mueller maneuver (‐4.4/‐3.4) group, compared to no change in the placebo group. On this basis we suggest that the large pressure swings associated with both respiratory resistance training and Mueller maneuvers may contribute to improvements in blood pressure. Our findings support additional studies aimed at assessing the effects of training on efferent mechanism(s), such as sympathetic outflow, that may underpin alterations in blood pressure.

Exaggerated blood pressure response (ExBPR) to exercise, often defined as peak systolic blood pressure (SBP)≥210mm Hg in men and ≥190mmHg in women, has limited clinical utility due to inconsistent prognostic data. Workload-indexed SBP, expressed as SBP/metabolic equivalent of task (MET) slope, has emerged as a potentially superior marker of cardiovascular risk. This study aims to evaluate the association of exercise SBP parameters with left ventricular (LV) remodeling and function, and to unveil which exercise SBP marker more accurately reflects adverse cardiac remodeling and function. We retrospectively studied 455 individuals who underwent echocardiography and treadmill testing within 1day at a single center in Korea. Echocardiographic parameters included left ventricular (LV) end-diastolic dimension (EDD), relative wall thickness (RWT) and e' velocity. SBP/MET slope was calculated as (peak-resting SBP)/(maximal METs-1). Participants with SBP/Met slope >6.2mm Hg/MET were older, had higher body mass index, and exhibited smaller LV EDD index, higher RWT, and lower e' velocity (all p<0.05). They also showed higher resting and peak SBP and lower exercise capacity. ExBPR was associated with similar structural and functional abnormalities but not with exercise capacity. In individuals without ExBPR, higher SBP/MET slope identified smaller LV EDD index, higher RWT, and lower e' velocity (all p<0.05). Multivariable analyses confirmed independent associations of SBP/MET slope with concentric LV structure represented by high RWT and lower e' velocity, beyond resting SBP. Adding SBP/MET slope to ExBPR improved prediction of reduced e' velocity (p=0.021). SBP/MET slope was independently associated with concentric LV structure and diastolic dysfunction, providing incremental clinical value over ExBPR in detecting subclinical cardiac abnormalities.

BackgroundExaggerated blood pressure response during exercise predicts future hypertension and cardiovascular events in general population and different patients groups. However, its clinical and prognostic implications in patients with aortic stenosis have not been previously evaluated.Methods and ResultsWe retrospectively studied 301 patients with moderate to severe asymptomatic aortic stenosis (aged 65±12 years) who underwent echocardiography and a modified Bruce exercise treadmill test. An exaggerated blood pressure response was defined as peak systolic blood pressure ≥190 mm Hg. An abnormal blood pressure response (either blunted or exaggerated) was found in 58% of patients and abnormal left ventricular geometry in 82%. There was no difference in the rates of abnormal blood pressure responses between patients with moderate and severe aortic stenosis ([exaggerated blood pressure response: 21% versus 22%, P=0.876] and [blunted blood pressure response: 35% versus 40%, P=0.647]). Patients with exaggerated blood pressure response (21%) were more likely to be older, have hypertension, higher pretest systolic blood pressure, left ventricular ejection fraction and mass, and increased arterial stiffness (all P<0.05). In a multivariate logistic regression analysis, an exaggerated blood pressure response was associated with higher pulse pressure/stroke volume index (odds ratio 2.45, 95% confidence interval 1.02–6.00, P=0.037) and left ventricular mass (odds ratio 2.04, 95% confidence interval 1.23–3.38, P=0.012) independent of age, hypertension, aortic annulus and left atrium diameter, and left ventricular ejection fraction.ConclusionsIn those with aortic stenosis, exaggerated blood pressure was strongly related to higher resting blood pressure values, left ventricular mass, and increased arterial stiffness independent of hypertension.

Background: Inspiratory muscle strength training (IMST) has attracted much attention in the intervention for hypertension in individuals with obstructive sleep apnea (OSA). In individuals with OSA, chronically elevated muscle sympathetic nerve activity (MSNA) may increase systemic vascular resistance (SVR), potentially leading to elevated resting blood pressure. To address this issue, a long-term IMST program (30 training breaths/day, 5 days/wk for 6 wk) has been reported effectively lower to mean arterial pressure (MAP) in older adults with OSA. However, the acute effects of IMST on MAP in individuals with OSA were unexplored, and thus the underlying mechanism is not fully understood. In young healthy adults, acute IMST has been shown to lower muscle sympathetic nerve activity (MSNA). This IMST-induced decrease in MSNA is presumably due to the repetitive increase in venous return, which inhibits sympathetic outflow via cardiopulmonary receptors. While it remains unclear whether the cardiopulmonary reflex is maintained in older adults with OSA compared to age-matched controls, it is assumed to be relatively preserved in older adults with OSA without cardiac hypertrophy. Purpose: This study aimed to elucidate whether there are differences in acute effects of IMST on SVR and BP between older adults with OSA and their age-matched counterparts. We hypothesized that a single session of IMST may lead comparable reductions in SVR in older adults with OSA compared to those without OSA. Methods: Eleven older adults with OSA (OSA; 9M/2F, 64 ± 8 yrs, mean ± SD) undergoing continuous positive airway pressure treatment and 7 adults without OSA (CON; 4M/3F, 65 ± 6 yrs) were studied. Following 3 minutes of rest, subjects performed 30 breaths per session (6 breaths/set, 5 sets) of IMST at 50–60% of maximal inspiratory pressure, with 2-minute intervals between sets. Beat-by-beat changes in systolic and diastolic BP (SBP and DBP, respectively), and CO were recorded continuously before and during IMST. SVR was calculated as MAP/CO. BPs, CO, and SVR were assessed by comparing the mean values from 30 seconds before IMST to those during the 3rd, 4th, and 5th sets of IMST and the percent change from baseline was also calculated. Results: In both groups, IMST reduced DBP and SVR, and increased CO (P &lt; 0.01). SBP significantly decreased by IMST only in the OSA group (P &lt; 0.01). The percent change in CO during IMST was lower in the OSA group compared to the CON group (P = 0.046), whereas the percent change in SVR showed no significant difference (P = 0.43). Conclusion: As we expected, the IMST-induced reduction in SVR was similar between groups. The effects of IMST on SVR were comparable between the groups; however, the OSA group exhibited a smaller increase in CO and a more pronounced reduction in MAP compared to age-matched control subjects. This study was supported by JSPS KAKENHI #21K11170 This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

The importance of exercise-induced exaggerated blood pressure (BP) response in endurance athletes is not known. To assess the hemodynamic parameters and metabolic profile in athletes with an exaggerated BP response to exercise. Forty-four endurance athletes underwent a maximal exercise test, a 24-h ambulatory blood pressure monitoring, a 24-h Holter assessment, and sampling of blood on two occasions: (a) during intense training and (b) following 3 weeks without training. During the training period, 11 athletes showed an exaggerated BP response to exercise, whereas seven of these 11 athletes also showed an exaggerated BP response during the resting period. Elevation in systolic BP was greater in athletes with an exaggerated BP response than athletes with a normal BP response to exercise (resting: 84 ± 22 vs. 60 ± 18 mmHg, P = 0.02; training: 100 ± 21 vs. 70 ± 18 mmHg, P = 0.004). During the training period, athletes with an exaggerated BP response to exercise showed higher systolic BP values on 24-h ambulatory blood pressure monitoring (136 ± 15 vs. 118 ± 8 mmHg, P = 0.02). During the resting period, athletes with an exaggerated BP response to exercise had lower apolipoprotein-A1 (1.3 ± 0.1 vs. 1.5 ± 0.2 g/l, P = 0.009), and higher SDNN (259 ± 47 vs. 209 ± 52 ms, P = 0.03) and pNN50 (0.4 ± 0.1 vs. 0.3 ± 0.1%, P = 0.05). These observations may represent the first sign of a slight metabolic disturbance associated with vascular wall abnormalities, although the parameters remain within normal values.

A comparison of the effects of inspiratory muscle strength and endurance training on exercise capacity, respiratory muscle strength and endurance, and quality of life in pacemaker patients with heart failure: A randomized study

New and effective strategies are needed to manage the autonomic and cardiovascular sequelae of obstructive sleep apnea (OSA). We assessed the effect of daily inspiratory muscle strength training (IMT) on sleep and cardiovascular function in adults unable to use continuous positive airway pressure (CPAP) therapy. This is a placebo-controlled, single-blind study conducted in twenty four adults with mild, moderate, and severe OSA. Subjects were randomly assigned to placebo or inspiratory muscle strength training. Subjects in each group performed 5 min of training each day for 6 w. All subjects underwent overnight polysomnography at intake and again at study close. We evaluated the effects of placebo training or IMT on sleep, blood pressure, and plasma catecholamines. Relative to placebo-trained subjects with OSA, subjects with OSA who performed IMT manifested reductions in systolic and diastolic blood pressures (-12.3 ± 1.6 SBP and -5.0 ± 1.3 DBP mmHg; P < 0.01); plasma norepinephrine levels (536.3 ± 56.6 versus 380.6 ± 41.2 pg/mL; P = 0.01); and registered fewer nighttime arousals and reported improved sleep (Pittsburgh Sleep Quality Index scores: 9.1 ± 0.9 versus 5.1 ± 0.7; P = 0.001). These favorable outcomes were achieved without affecting apneahypopnea index. The results are consistent with our previously published findings in normotensive adults but further indicate that IMT can modulate blood pressure and plasma catecholamines in subjects with ongoing nighttime apnea and hypoxemia. Accordingly, we suggest IMT offers a low cost, nonpharmacologic means of improving sleep and blood pressure in patients who are intolerant of CPAP.