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Chen Ju-Yi - - 2010
Analysis of short-term (5-minute) heart rate variability (HRV) may provide useful information about autonomic nervous control of the cardiovascular system. The aim of the present study was to evaluate the association between the results of treadmill exercise testing (TET) and short-term (5-minute) HRV. Patients undertaking TET were anteriorly evaluated with ...
Boettger Silke - - 2010
PURPOSE: Various measures of autonomic function have been developed, and their applicability and significance during exercise are controversial. METHODS: Physiological data were therefore obtained from 23 sport students before, during, and after exercise. Measures of R-R interval variability, QT variability index (QTvi), and electrodermal activity (EDA) were calculated. We applied ...
Keteyian Steven J - - 2010
Prior exercise research and the recently completed HF-ACTION (Heart Failure and A Controlled Trial Investigating Outcomes of Exercise Training) trial indicate that regular exercise represents an effective therapy in the management of patients with stable chronic heart failure (HF) due to left ventricular systolic dysfunction. This review summarizes the results ...
Earnest Conrad P - - 2010
Obesity, physical inactivity and altered estrogen metabolism play an integrated role contributing to the disease risk profiles of postmenopausal women. These same risk factors also affect modulation of the autonomic nervous system (ANS). We examined 332 postmenopausal, overweight, previously sedentary women (mean+/-SD; age, 57.6+/-6.3 years; weight, 84.3+/-11.9kg; BMI, 31.7+/-3.7kg/m(2)) participating ...
Ikeda Nahoko - - 2010
To explore the acute effects of submaximal exercise on blood rheology and sympathetic nerve activity. The effects of exercise (20 or 80 Watts (W)) on blood rheology and sympathetic nerve activity were assessed in 10 healthy Japanese men. Blood sampling and heart rate variability (HRV) recording were performed during 20-min ...
Grimaldi D - - 2010
OBJECTIVE: To test the autonomic control of cardiovascular reflexes and heart rate variability (HRV) at rest and during orthostatic stress in narcolepsy with cataplexy (NC). METHODS: Ten NC patients with a hypocretin deficit and 18 control subjects underwent head-up tilt test (HUTT), Valsalva manoeuvre, deep breathing and cold face under ...
Kawasaki Tatsuya - - 2010
AIMS: An attenuated heart rate response to exercise, termed chronotropic incompetence (CI), has been reported to be an independent predictor of cardiovascular mortality. We examined the change in autonomic function during exercise testing and correlated the results with CI. METHODS AND RESULTS: Exercise testing using a bicycle ergometer was performed ...
Bricout V?ronique-Aur?lie - - 2010
BACKGROUND: The use of heart rate variability (HRV) in the management of sport training is a practice which tends to spread, especially in order to prevent the occurrence of states of fatigue. OBJECTIVE: To estimate the HRV parameters obtained using a heart rate recording, according to different loads of sporting ...
Olson Thomas P TP Department of Internal Medicine and Anesthesiology, Mayo Clinic, Rochester, Minn 55905, - - 2010
Whether locomotor muscle afferent neural activity contributes to exercise hyperpnea and symptoms of dyspnea in heart failure (HF) is controversial. We examined the influence of metaboreceptor stimulation on ventilation with and without maintaining end-exercise end-tidal CO(2) levels. Eleven patients with HF aged 51+/-5 years (ejection fraction, 32+/-3%; New York Heart ...
Vallais F - - 2010
The baroreflex is one of the most important short-term cardiovascular autonomic control mechanisms. Its interactions with other reflexes, mainly cardiopulmonary reflexes, are of paramount importance in controlling heart rate. This study assesses the coupling between baroreflex and respiration during a progressive bicycle mild dynamical exercise. The coupling was assessed by ...
Mendes Renata Gonçalves - - 2010
OBJECTIVE: Coronary artery bypass grafting (CABG) is accompanied by severe impairment of cardiac autonomous regulation (CAR). This study aimed to determine whether a short-term physiotherapy exercise protocol post-CABG, during inpatient cardiac rehabilitation (CR), might improve CAR. DESIGN: Seventy-four patients eligible for CABG were recruited and randomised into physiotherapy exercise group ...
Antunes-Correa Ligia M - - 2010
We compared the effects of exercise training on neurovascular control and functional capacity in men and women with chronic heart failure (HF). Forty consecutive HF outpatients from the Heart Institute, University of Sao Paulo, Brazil were divided into the following four groups matched by age: men exercise-trained (n = 12), ...
Pafili Zoe K ZK Department of Sports Medicine and Biology of Physical Activity, Faculty of Physical Education and Sports Sciences, University of Athens , - - 2010
The effect of resistance exercise on blood lipids is not clear yet. The purpose of this study was to examine the cholesterol responses to a heavy resistance leg press exercise emphasizing on the eccentric movement 24 and 48 hours following exercise and to quantify the cardiorespiratory responses of the exercise ...
Vigo Daniel E - - 2010
OBJECTIVE: Acute hypobaric hypoxia is associated with autonomic changes that bring a global reduction of linear heart rate variability (HRV). Although changes in nonlinear HRV can be associated with physiologic stress and are relevant predictors of fatal arrhythmias in ischemic heart disease, to what extent these components vary in sudden ...
Goulopoulou Styliani - - 2010
This study examined the effect of aerobic exercise training on vagal and sympathetic influences on the modulations of heart rate and systolic blood pressure in response to an oral glucose load in obese individuals with and without type 2 diabetes mellitus (T2D). Beat-to-beat arterial pressure and continuous electrocardiogram were measured ...
Kiviniemi Antti M - - 2009
PURPOSE:: To test the utility of heart rate variability (HRV) in daily exercise prescription in moderately active (~2 exercises/week) men and women. METHODS:: Twenty-one men and thirty-two women were divided into standard training (ST: M7/F7), HRV-guided training (HRVI: M7/F7; HRV-II: F10), and control (M7/F8) groups. The eight-week aerobic training period ...
Munk Peter S - - 2010
Low time domain measures of heart rate variability (HRV) have been shown to predict outcome after myocardial infarction (MI). The predictive value of HRV, when measured in patients with coronary artery disease (CAD) without MI is less clear. Further, little is known about the mechanisms of how autonomic imbalance affects ...
Soares-Miranda Luisa - - 2009
BACKGROUND: Aerobic exercise leads to reduced sympathetic and increased cardiac vagal modulation, providing an antiarrhythmic effect. The optimal exercise intensity to promote this adaptation remains undefined. The aims of the present investigation were twofold. First, to examine differences in heart rate variability (HRV) measures in participants with different levels of ...
Al Haddad Hani - - 2009
PURPOSE: To assess the effect of supramaximal intermittent exercise on long-term cardiac autonomic activity, inferred from heart rate variability (HRV). METHODS: Eleven healthy males performed a series of two consecutive intermittent 15-s runs at 95% VIFT (i.e., speed reached at the end of the 30-15 Intermittent Fitness Test) interspersed with ...
Charlot K - - 2009
Photoplethysmography variability (PPGV) is currently considered to be a good surrogate to heart rate variability (HRV) measurements using the time between two pulse waves instead of RR intervals. Nevertheless, the interchangeability between HRV and PPGV has never been evaluated in situations with severe alterations in the autonomic nervous system (ANS). ...
Kaikkonen Piia - - 2010
The overload principle of training states that training load (TL) must be sufficient to threaten the homeostasis of cells, tissues, organs, and/or body. However, there is no "golden standard" for TL measurement. The aim of this study was to examine if any post-exercise heart rate variability (HRV) indices could be ...
Esco Michael R - - 2010
OBJECTIVE: There is limited research available regarding a possible relationship between resting heart rate variability (HRV) and post-exercise heart rate recovery (HRR). The aim of this study was to examine the relationship between resting HRV and HRR after maximal exercise. METHODS: Sixty-six college age men participated in this study. HRV ...
Grant Catharina C - - 2009
The study investigated whether supine-measured HRV indicators, and/or HRV indicators measured during orthostatic stress are related to conventional measures of exercise and performance ability such as VO(2max). Only two significant correlations (p<0.05) out of 30 tests were found between supine-determined HRV indicators and conventional measures. In contrast, fifteen of the ...
Whellan David J DJ Departmentof Cardiology, Jefferson Medical College, Philadelphia, Pennsylvania 19107, - - 2009
With the emergence of large multicenter trials over the past 20 years, the numbers of investigators involved and publications resulting from each study have grown exponentially. An efficient, fair, and effective way to establish authorship on study-related manuscripts could diminish conflict among the investigators and help ensure robust and timely ...
Gladwell V F - - 2010
Cardioprotective benefits of exercising at vigorous intensities are known, but reservations remain in prescribing such activity to the untrained population, due to a perceived risk of cardiac events. Few studies have investigated the recovery of the autonomic nervous system (ANS) after a single exercise bout, especially following vigorous exercise in ...
Amin Ahmad S - - 2009
Ventricular arrhythmia occurrence during exercise is reported in Brugada syndrome (BrS). Accordingly, experimental studies suggest that BrS-linked SCN5A mutations reduce sodium current more at fast heart rates. Yet, the effects of exercise on the BrS ECG phenotype have not been studied. We aimed to assess ECG responses to exercise in ...
Mavrogeni Sophie - - 2009
In b-thalassemia, myocardial iron overload contributes to heart failure, despite chelation treatment. We hypothesized that myocardial T2*, an index of iron overload, influences patients' physical activity. We assessed a thalassemic population by both cardiovascular magnetic resonance imaging (CMR) and ergospirometry test. Sixty-six thalassemic patients aged 27 (19-40) years, 30 without ...
Kanaley J A - - 2009
To examine the responsiveness of cardiac autonomic function and baroreflex sensitivity (BRS) to exercise training in obese individuals without (OB) and with type 2 diabetes (ObT2D). Subjects were tested in the supine position and in response to a sympathetic challenge before and after a 16-week aerobic training program. All testing ...
Ng Jason - - 2009
Although frequency-domain analysis of heart rate variability (HRV) has been performed in the setting of exercise and recovery from exercise, the relationship of specific frequency components to sympathetic and parasympathetic inputs has not been validated in this setting. The aim of this study is to evaluate the relationship of frequency ...
Zupet Petra - - 2009
The influence of hypoxia on heart rate variability (HRV) has been studied under resting conditions with mixed results. Differences have been found in physiological responses to normobaric versus hypobaric hypoxia. Our aim was to study the influence of hypobaric hypoxia on HRV during physical exercise to determine whether HRV changes ...
Vorluni L - - 2010
The effects of cardiopulmonary baroreceptors and muscle mechanoreceptors stimulation on cardiac baroreflex sensitivity (BRS), and heart rate variability (HRV) were evaluated by measuring continuously and non-invasively systolic blood pressure (SBP) and pulse interval (PI) during upright and supine passive cycling. BRS and HRV were evaluated with the cross-correlation method (xBRS) ...
Jae Sae Young - - 2009
Although studies have shown an inverse association between cardiorespiratory fitness (CRF) and C-reactive protein (CRP) levels, the underlying mechanisms are not fully understood. There is emerging evidence that autonomic nervous system function is related to CRP levels. Because high CRF is related to improved autonomic function, we hypothesized that the ...
Stener-Victorin Elisabet - - 2009
We have recently shown that polycystic ovary syndrome (PCOS) is associated with high muscle sympathetic nerve activity (MSNA). Animal studies support the concept that low-frequency electroacupuncture (EA) and physical exercise, via stimulation of ergoreceptors and somatic afferents in the muscles, may modulate the activity of the sympathetic nervous system. The ...
Lavie Carl J - - 2009
Despite major advances in the field of cardiovascular (CV) diseases, heart failure (HF) continues to result in considerable CV morbidity and mortality and accounts for an increasing number of acute hospitalizations in adult patients. Recent major trials have focused on exercise training programs and the widely available nutraceutical omega-3 polyunsaturated ...
Mendonca Goncalo Vilhena - - 2009
OBJECTIVES: To apply both autoregressive (AR) and fast Fourier transform (FFT) spectral analysis at rest, during two different dynamic exercise intensities and in recovery from maximal exercise and to compare raw and normalized powers obtained with both methods. METHODS: Sixteen participants (age 22.3 +/- 4.3 year) performed resting, submaximal and ...
Mukherjee Shalini - - 2009
BACKGROUND: Epilepsy is associated with imbalance of sympathetic and parasympathetic activity which may lead to sudden unexplained death in epilepsy (SUDEP). Well-controlled (WcE) and intractable epilepsy (IE) subjects may present different autonomic profiles, which can be helpful in explaining the predisposition of the latter to SUDEP. PURPOSE: To compare inter-ictal ...
Fogt Donovan L - - 2009
Chronic fatigue/physical exhaustion (FPE) impacts combat readiness but is difficult to identify. We tested the hypothesis that resting heart rate variability (HRV), including both time- and frequency-domain assessments, would correlate with hydration status and aerobic capacity in military recruit-age men and women with varying fitness levels. Cardiac interbeat intervals were ...
Buchheit M - - 2009
The aim of the present study was to assess the influence of body posture on post-submaximal exercise parasympathetic reactivation and to examine whether this influence was preserved under a heightened sympathetic background. On four occasions, eleven moderately trained subjects (22.1 +/- 3.0 years old) performed, in random order, two consecutive ...
Morris Norman R NR School of Physiotherapy and Exercise Science, Griffith University, Gold Coast Campus, Gold Coast, QLD 4222, Australia. - - 2009
Circulation time (the transit time for a bolus of blood through the circulatory system) is a potential index of cardiac dysfunction in chronic heart failure (HF). In healthy subjects, circulation time falls as cardiac output (Q) rises during exercise, however little is known about this index in HF. In this ...
Lauer Michael S - - 2009
Autonomic nervous system function is assessed in the clinic by measuring resting heart rate, heart rate variability, or heart rate recovery following exercise. Each of these measures is a strong predictor of cardiovascular risk and all-cause mortality in primary and secondary prevention settings. These measures have been used to identify ...
La Fountaine Michael F - - 2009
Heart rate variability (HRV) and complexity (HRC) were calculated at rest and during an isometric hand grip test (IHGT) within 48-hours (48 h) and two weeks (Week Two) of a concussion in athletes (CG) and control subjects. No differences were present at rest or in HRV during IGHT. HRC was ...
Brown S J - - 2009
The aims of this investigation were to identify possible associations between the resting high frequency component of heart rate variability and measures of ventilatory efficiency, determined during exercise, in a group of endurance trained athletes. V'E, V'CO2, and V'O2 were measured during incremental exercise up to the anaerobic threshold (AT) ...
Blain Grégory - - 2009
To test the hypothesis that cycling exercise modulates heart rate variability (HRV), we applied a short-time Fourier transform on the electrocardiogram of subjects performing a maximal graded cycling test. A pedaling frequency component (PFC) in HRV was continuously observed over the time course of the exercise test and extracted from ...
Swanson Kimberly S - - 2009
Decreased HRV has been consistently associated with increased cardiac mortality and morbidity in HF patients. The aim of this study is to determine if a 6-week course of heart rate variability (HRV) biofeedback and breathing retraining could increase exercise tolerance, HRV, and quality of life in patients with New York ...
Heffernan Kevin S - - 2009
African Americans have a greater prevalence of hypertension and diabetes compared with white Americans, and both autonomic dysregulation and inflammation have been implicated in the etiology of these disease states. The purpose of this study was to examine the cardiac autonomic and systemic inflammatory response to resistance training in young ...
Monda M - - 2009
Caffeine induces modifications of activity of the autonomic nervous system. This study analyzed the effect of a cup of espresso coffee on the heart rate variability (HRV) power spectral analysis, which is a method providing evaluation of the sympathetic and parasympathetic discharge. In young, healthy sedentary subjects (10 male, 10 ...
Vallais Frederic - - 2009
In the literature, several methods have been proposed for the assessment of the baroreflex sensitivity from spontaneous variability of heart period and systolic arterial pressure. The present study compares the most utilized approaches for the evaluation of the spontaneous baroreflex sensitivity (i.e. sequence-based, spectral, cross-spectral and model-based techniques) over a ...
Piallat Brigitte - - 2009
OBJECTIVE: Electrical high-frequency stimulation (HFS) of deep brain structures has been successfully used as a treatment for patients with movement disorders. The mechanisms of HFS allowing therapeutic clinical effects remain unclear, which justifies experimental studies to address these questions. These experiments require an external stimulator, which may offer the possibility ...
Ino-Oka Eiji - - 2009
BACKGROUND: Exercise is recommended for the treatment and prevention of cardiac disorders. Relaxation of the sympathetic nervous system has been considered to be one of the therapeutic mechanisms. However, the means by which the level of daily physical activity affects sympathetic activity remains unclear. OBJECTIVE: To evaluate the effects of ...
Buchheit Martin - - 2009
The 30-15 Intermittent Fitness Test (30-15IFT) is an attractive alternative to classic continuous incremental field tests for defining a reference velocity for interval training prescription in team sport athletes. The aim of the present study was to compare cardiorespiratory and autonomic responses to 30-15IFT with those observed during a standard ...
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