Effects of Low-Intensity Exercise Conditioning on Blood Pressure, Heart Rate, and Autonomic Modulation of Heart Rate in Men and Women with Hypertension

2009 ◽  
Vol 11 (2) ◽  
pp. 129-143 ◽  
Author(s):  
Lien P.T. Hua ◽  
C. Ann Brown ◽  
Sylvia J.M. Hains ◽  
Marshall Godwin ◽  
Joel L. Parlow
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Diastolic Blood Pressure ◽  
Baroreflex Sensitivity ◽  
Autonomic Modulation ◽  
Men And Women ◽  
Low Intensity ◽  
Walking Program ◽  
Spontaneous Baroreflex ◽  
Low Intensity Exercise

Untreated hypertension increases cardiovascular risk 2-fold to 3-fold, leading to serious cardiovascular problems that include left ventricular hypertrophy, stroke, ischemic heart disease, myocardial infarction, vascular disease, renal disease, and death. Exercise conditioning is recommended as one of the initial treatments for hypertension. The purpose of this pretest—posttest study was to quantify the effects of a 12-week home-based low-intensity exercise conditioning (walking) program in hypertensive men and women on systolic and diastolic blood pressure, heart rate, and autonomic modulation of heart rate. A total of 20 mildly hypertensive men and women who were assigned to a structured exercise (walking) program were compared with a control group of 20 nonexercising mildly hypertensive participants. Electrocardiographic heart rate and R-R interval data and beat-by-beat arterial blood pressure data were collected continuously for 10 min with participants in the supine and standing postures and during low-intensity steady-state exercise. The results show that systolic and diastolic blood pressure and R-R interval decreased and spontaneous baroreflex sensitivity increased in the exercise group. The decline in blood pressure was significant statistically and clinically. The increase in spontaneous baroreflex sensitivity indicates that the ability of the cardiovascular system to respond rapidly to changing stimuli improved after the 12-week walking protocol. The low-intensity exercise conditioning program achieved a training effect in this population.

Heart rate variability following coronary artery bypass graft surgery as a function of recovery time, posture, and exercise

2004 ◽  
Vol 82 (7) ◽  
pp. 457-464 ◽  
Author(s):  
C Ann Brown ◽  
Larry A Wolfe ◽  
Sylvia Hains ◽  
Glorianne Ropchan ◽  
Joel Parlow
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Baroreflex Sensitivity ◽  
Artery Bypass ◽  
Bypass Graft ◽  
Interval Data ◽  
Artery Bypass Graft ◽  
Low Intensity ◽  
Spontaneous Baroreflex ◽  
Low Intensity Exercise

This study examined the claim made by Niemela et al. (1992) that the decline in heart rate variability after coronary artery bypass graft surgery is irreversible. We tested six women and 16 men six and 12 weeks postoperative in three postures: in the supine position, in the standing position, and during low-intensity steady-state exercise. Beat-by-beat arterial blood pressure and electrocardiographic R–R interval data were collected continuously for 10 min in each condition. R–R interval data were analyzed with spectral analysis; baroreflex data were analyzed using the sequence method. Our results show that the indices of parasympathetic modulation improved over time, as seen by an | increased spontaneous baroreflex sensitivity and parasympathetic indicator, that both indices were affected by posture, and that spontaneous baroreflex sensitivity was also affected by low-intensity exercise. The effects of posture are consistent with attenuated responses of healthy older subjects to orthostatic stress. Similarly, the effects of low-intensity exercise are consistent with findings in healthy subjects. We found that spontaneous baroreflex sensitivity declined during exercise, whereas, in healthy subjects, this is maintained during low-intensity steady-state exercise. Our results of significant functional recovery between six and 12 weeks postoperative suggest that at least some of the autonomic dysfunction following surgery is temporary. Previously, no such duration of study has lasted longer than four or six weeks following cardiac surgery, which may not have been long enough to show significant functional restoration in heart rate variability.Key words: heart rate variability, spontaneous baroreflex sensitivity, CABG surgery, posture, exercise.

Obesity does not Impair Ambulatory Cardiovascular and Autonomic Responses Post-exercise

2021 ◽  
Author(s):  
Gabriel Kolesny Tricot ◽  
Fabiula Isoton Isoton Novelli ◽  
Lucieli Teresa Cambri
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Diastolic Blood Pressure ◽  
Maximal Exercise ◽  
Young Men ◽  
Autonomic Modulation ◽  
Incremental Test ◽  
Post Exercise ◽  
Cardiac Autonomic Modulation ◽  
Main Effect

AbstractThis study aimed to assess whether obesity and/or maximal exercise can change 24 h cardiac autonomic modulation and blood pressure in young men. Thirty-nine men (n: 20; 21.9±1.8 kg·m−2, and n: 19; 32.9±2.4 kg·m−2) were randomly assigned to perform a control (non-exercise) and an experimental day exercise (after maximal incremental test). Cardiac autonomic modulation was evaluated through frequency domain heart rate variability (HRV). Obesity did not impair the ambulatory HRV (p>0.05), however higher diastolic blood pressure during asleep time (p=0.02; group main effect) was observed. The 24 h and awake heart rate was higher on the experimental day (p<0.05; day main effect), regardless of obesity. Hypotension on the experimental day, compared to control day, was observed (p<0.05). Obesity indicators were significantly correlated with heart rate during asleep time (Rho=0.34 to 0.36) and with ambulatory blood pressure(r/Rho=0.32 to 0.53). Furthermore, the HRV threshold workload was significantly correlated with ambulatory heart rate (r/Rho=− 0.38 to−0.52). Finally, ambulatory HRV in obese young men was preserved; however, diastolic blood pressure was increased during asleep time. Maximal exercise caused heart rate increase and 24h hypotension, with decreased cardiac autonomic modulation in the first hour, regardless of obesity.

scholarly journals Effect of Chair aerobics as low intensity exercise training on heart rate, blood pressure and six minute walk distance in post coronary artery bypass graft surgery patients through phase I cardiac rehabilitation

2016 ◽  
Vol 13 (1) ◽  
pp. 19-23
Author(s):  
Shaili Thapa ◽  
Renu B. Pattanshetty
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Exercise Training ◽  
Cardiac Rehabilitation ◽  
Phase I ◽  
Walk Distance ◽  
Low Intensity ◽  
Low Intensity Exercise ◽  
Minute Walk Distance ◽  
Minute Walk

Background and Aims: Cardiac Rehabilitation after Coronary arteries bypass graft (CABG) surgery is known to have several favorable effects. Aerobics exercise in the form of chair aerobics shown to have beneficial effects with little evidence. The purpose of the present study was to demonstrate the effect of chair aerobics as low intensity exercise training in heart rate, blood pressure and six minute walk distance in post CABG patients during phase I cardiac rehabilitation.   Methods: It was a single centre, prospective study carried out in Indian tertiary care set-up. Fifty patients post CABG patients were included. Chair aerobics as a low intensity exercise training was given.  Pre and post-exercise outcome measurements in the form of heart rate, blood pressure and six-minute walk distance test were recorded. Results: The study showed statistically significant difference in systolic blood pressure (p= 0.018), heart rate (p≤0.001) and increase in six minute walk distance (p≤0.001). Conclusion: Chair aerobics as low intensity exercise training demonstrated improvement in heart  rate, systolic blood pressure and six minute walk distance test in subjects with CABG through phase I  cardiac rehabilitation.  Nepalese Heart Journal 2016; 13(1) 19-23

Synergistic Effects of Low-Intensity Exercise Conditioning and β-Blockade on Cardiovascular and Autonomic Adaptation in Pre- and Postmenopausal Women With Hypertension

2012 ◽  
Vol 15 (4) ◽  
pp. 433-442 ◽  
Author(s):  
Catherine L. Goldie ◽  
C. Ann Brown ◽  
Sylvia M. J. Hains ◽  
Joel L. Parlow ◽  
Richard Birtwhistle
Keyword(s):  
Baroreflex Sensitivity ◽  
Synergistic Effects ◽  
Exercise Group ◽  
Rate Pressure Product ◽  
Control Group ◽  
Cardiac Autonomic Function ◽  
Low Intensity ◽  
Walking Program ◽  
Low Intensity Exercise ◽  
Sedentary Women

The effects of a 12-week low-intensity exercise conditioning program (walking) on blood pressure (BP), heart rate (HR), rate–pressure product (RPP), and cardiac autonomic function were measured in 40 sedentary women with hypertension. Women were assigned to either an exercise group ( n = 20) or a control group ( n = 20), matched for β-blockade treatment. They underwent testing at the beginning and at the end of the 12-week study period in three conditions: supine rest, standing, and low-intensity steady state exercise. The exercise group participated in a 12-week, low-intensity walking program, while the control group continued with usual sedentary activity. Compared with the control group, women in the exercise group showed reductions in systolic and diastolic BP and RPP (i.e., the estimated cardiac workload). β-Blockers increased baroreflex sensitivity and lowered BP and HR in all participants; however, those in the exercise group showed the effects of both treatments: a greater reduction in HR and RPP. The combination of exercise training and β-blockade produces cardiac and autonomic adaptations that are not observed with either treatment alone, suggesting that β-blockade enhances the conditioning effects of low-intensity exercise in women with hypertension.

Low-intensity exercise training decreases cardiac output and hypertension in spontaneously hypertensive rats

1997 ◽  
Vol 273 (6) ◽  
pp. H2627-H2631 ◽  
Author(s):  
Acácio Salvador Véras-Silva ◽  
Katt Coelho Mattos ◽  
Nilo Sérgio Gava ◽  
Patricia Chakur Brum ◽  
Carlos Eduardo Negrão ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cardiac Output ◽  
Exercise Training ◽  
High Intensity ◽  
Peripheral Resistance ◽  
High Intensity Exercise ◽  
Spontaneously Hypertensive ◽  
Low Intensity ◽  
Low Intensity Exercise

The decrease in cardiac sympathetic tone and heart rate after low-intensity exercise training may have hemodynamic consequences in spontaneously hypertensive rats (SHR). The effects of exercise training of low and high intensity on resting blood pressure, cardiac output, and total peripheral resistance were studied in sedentary ( n = 17), low- ( n = 17), and high-intensity exercise-trained ( n = 17) SHR. Exercise training was performed on a treadmill for 60 min, 5 times per week for 18 weeks, at 55% or 85% maximum oxygen uptake. Blood pressure was evaluated by a cannula inserted into the carotid artery, and cardiac output was evaluated by a microprobe placed around the ascending aorta. Low-intensity exercise-trained rats had a significantly lower mean blood pressure than sedentary and high-intensity exercise-trained rats (160 ± 4 vs. 175 ± 3 and 173 ± 2 mmHg, respectively). Cardiac index (20 ± 1 vs. 24 ± 1 and 24 ± 1 ml ⋅ min−1 ⋅ 100 g−1, respectively) and heart rate (332 ± 6 vs. 372 ± 14 and 345 ± 9 beats/min, respectively) were significantly lower in low-intensity exercise-trained rats than in sedentary and high-intensity exercise-trained rats. No significant difference was observed in stroke volume index and total peripheral resistance index in all groups studied. In conclusion, low-intensity, but not high-intensity, exercise training decreases heart rate and cardiac output and, consequently, attenuates hypertension in SHR.

Autonomic Cardiovascular Regulation in the Newborn

2012 ◽  
pp. 201-221
Author(s):  
Peter Andriessen
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Baroreflex Sensitivity ◽  
Heart Rate Response ◽  
Function Analysis ◽  
Feedback System ◽  
Cardiovascular Regulation ◽  
Interval Change ◽  
Method Transfer ◽  
Spontaneous Baroreflex

This paper reviews the baroreflex mediated heart rate response in human infants with a focus on data acquisition, signal processing and autonomic cardiovascular modeling. Baroreflex mediated heart rate response is frequently used as an estimate of autonomic cardiovascular regulation. Baroreflex mediated heart rate response may be viewed in terms of a negative-feedback system. To study fluctuations in this feedback system, continuous registration of ECG and blood pressure waveforms are required. From these waveforms, time series of R-R interval and blood pressure values are derived. This paper focus on spontaneous baroreflex sensitivity (e.g., R-R interval change per unit of arterial blood pressure change, ms/mmHg) calculated from cross-spectral analysis of spontaneous occurring changes in R-R interval and blood pressure. Despite different methodology (sequence method; transfer function analysis; head-up tilt) there is fairly good agreement of spontaneous baroreflex sensitivity values during homeostasis. Preterm infants and term newborns have values of 2-4 and 10-15 ms/mmHg, respectively. These values are much lower than found in adults, approximately 25 ms/mmHg. The clinical relevance of a limited baroreflex function may be that acute perturbations of the cardiovascular system are poorly counteracted and may result in poor cerebral perfusion.

Short-term couplings of the cardiovascular system in pregnant women suffering from pre-eclampsia

2010 ◽  
Vol 368 (1918) ◽  
pp. 2237-2250 ◽  
Author(s):  
Maik Riedl ◽  
Alexander Suhrbier ◽  
Holger Stepan ◽  
Jürgen Kurths ◽  
Niels Wessel
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Systolic Blood Pressure ◽  
Pregnant Women ◽  
Diastolic Blood Pressure ◽  
Baroreflex Sensitivity ◽  
External Input ◽  
Sensitivity Estimation ◽  
Maternal Morbidity And Mortality ◽  
Nonlinear Form

Pre-eclampsia (PE), a serious pregnancy-specific disorder, causes significant neonatal and maternal morbidity and mortality. Recent studies showed that cardiovascular variability parameters as well as the baroreflex sensitivity remarkably improve its early diagnosis. For a better understanding of the dynamical changes caused by PE, in this study the coupling between respiration, systolic and diastolic blood pressure, and heart rate is investigated. Thirteen datasets of healthy pregnant women and 10 of subjects suffering from PE are included. Nonlinear additive autoregressive models with external input are used for a model-based coupling analysis following the idea of Granger causality. To overcome the problem of misdetections of standard methods in systems with a dominant driver, a heuristic ensemble approach is used here. A coupling is assumed to be real when existent in more than 80 per cent of the ensemble members, and otherwise denoted as artefacts. As the main result, we found that the coupling structure between heart rate, systolic blood pressure, diastolic blood pressure and respiration for healthy subjects and PE patients is the same and reliable. As a pathological mechanism, however, a significant increased respiratory influence on the diastolic blood pressure could be found for PE patients ( p =0.003). Moreover, the nonlinear form of the respiratory influence on the heart rate is significantly different between the two groups ( p =0.002). Interestingly, the influence of systolic blood pressure on the heart rate is not selected, which indicates that the baroreflex sensitivity estimation strongly demands the consideration of causal relationships between heart rate, blood pressure and respiration. Finally, our results point to a potential role of respiration for understanding the pathogenesis of PE.

Sign in / Sign up

Export Citation Format

Share Document