Search Results
Results 401 - 450 of 1334
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Kang Jie - - 2009
To examine whether the validity of perception-based intensity regulation would be affected by exercise duration, 20 subjects were recruited to complete a maximal exercise test (GXT) and four submaximal trials of varying duration and intensity using a cyle ergometer. During GXT, ratings of perceived exertion (RPE), oxygen uptake VO2, heart ...
Chaffin Morgan E - - 2008
The purpose of this study was to investigate the pacing pattern and associated physiological effects in competitive cyclists who performed a 30-minute maximal cycling test. Measurements included oxygen uptake (V O2), heart rate (HR), blood lactate concentration (BLC), rating of perceived exertion (RPE), and work rate in watts. Twelve well-trained ...
Goekint Maaike - - 2008
PURPOSE: To examine the influence of a selective noradrenaline reuptake inhibitor (SNRI) on the exercise-induced increase in circulating brain-derived neurotrophic factor (BDNF). METHODS: In a double-blind, placebo-controlled, crossover design, 11 young, healthy male subjects were treated with either placebo or reboxetine. On each occasion, they performed a 60-min cycling exercise ...
Cheng Teddy M - - 2008
The first objective of this paper is to introduce a nonlinear system to model the heart rate (HR) response during and after treadmill walking exercise. The model is a feedback interconnected system that has components to describe the central and peripheral local responses to exercise and their interactions. The parameters ...
Okamoto Takanobu - - 2009
The aim of this study was to investigate the effect of low-intensity resistance exercise with slow lifting and lowering (LSL) on plasma endothelin-1 (ET-1) and noradrenalin concentrations in young healthy adults. Eight healthy males participated in this study (age 19.0 +/- 0.5 years, mean +/- SD). The LSL performed the ...
Zhang Gus Q - - 2009
An increasing body of scientific research and observational evidence indicates that resting heart rate (HR) is inversely related to the lifespan among homeothermic mammals and within individual species. In numerous human studies with patients stratified by resting HR, increased HR is universally associated with greater risk of death. The correlation ...
Ba Abdoulaye - - 2009
Because blood acidosis and arterial oxygenation (PaO(2)) play key roles in the chemoreflex control of cardiac activity, we hypothesized that heart rate (HR) decay rate after maximal exercise may be linked to post-exercise increase in blood lactate (LA) level and/or the resting PaO(2). Twenty healthy subjects and thirty five patients ...
Vercruyssen F - - 2009
To evaluate the physiological demands of kitesurfing, ten elite subjects performed an incremental running test on a 400-m track and a 30-min on-water crossing trial during a light crosswind (LW, 12-15 knots). Oxygen uptake (V(O)(2)) was estimated from the heart rate (HR) recorded during the crossing trial using the individual ...
Kenwright D A - - 2008
We show that the transitions which occur between close orders of synchronization in the cardio-respiratory system are mainly due to modulation of the cardiac and respiratory processes by low-frequency components. The experimental evidence is derived from recordings on healthy subjects at rest and during exercise. Exercise acts as a perturbation ...
Giannaki Christoforos D - - 2008
Recent studies have reported evidence of both a short-term and a more sustained reduction in left ventricular diastolic function after prolonged strenuous exercise. Interpretation of this data is confounded by alterations in heart rate (HR) post-exercise. The purpose of this study was to investigate the association between HR and diastolic ...
Sadrzadeh Rafie Amir H - - 2008
BACKGROUND: Although the prognostic power of exercise capacity has been demonstrated, the relative prognostic potential of other hemodynamic responses has not been thoroughly investigated. We aimed to assess the prognostic power of double product (DP) parameters in patients referred for standard exercise testing. DESIGN: A retrospective cohort study. METHODS: Analyses ...
Gondoni L A - - 2009
BACKGROUND AND AIMS: Heart rate (HR) response to exercise has not been fully described in the obese. We wanted to study the differences between obese and non-obese patients in HR behavior during an exercise stress test and to determine whether these differences influence exercise capacity. METHODS AND RESULTS: We studied ...
Wirnitzer Katharina C - - 2008
The purpose of this descriptive study was to examine the exercise intensity of a mountain bike (MTB) marathon race lasting 8 days. Seven amateur MTBers (age 33.6 +/- 3.0 years, height 1.67 +/- 0.5 m, body mass 58.4 +/- 9.9 kg) completing the Transalp Challenge 2004 were involved in the ...
Oneda Bruna - - 2008
The aim of this study was to determine whether estrogen therapy enhances postexercise muscle sympathetic nerve activity (MSNA) decrease and vasodilation, resulting in a greater postexercise hypotension. Eighteen postmenopausal women received oral estrogen therapy (ET; n=9, 1 mg/day) or placebo (n=9) for 6 mo. They then participated in one 45-min ...
Davis W Jackson - - 2008
We evaluated the effects of concurrent strength and aerobic endurance training on cardiovascular and cardiorespiratory adaptations in college athletes and compared two concurrent exercise (CE) protocols. Separate experiments were performed on 30 women (mean age 19.6 years) and 20 men (20.4 years). In both experiments, subjects were divided into two ...
Gormley Shannan E - - 2008
PURPOSE: To determine whether various intensities of aerobic training differentially affect aerobic capacity as well as resting HR and resting blood pressure (BP). METHODS: Sixty-one health young adult subjects were matched for sex and VO2max and were randomly assigned to a moderate- (50% VO2 reserve (VO2R), vigorous (75% VO2R), near-maximal-intensity ...
Hilliard Anthony A - - 2008
Clinical practice guidelines for patients with atrial fibrillation (AF) recommended a heart rate (HR) of 60 to 80 beats/min at rest and 90 to 115 at moderate exercise. The degree to which HR control at rest and with exercise in patients with AF complies with these recommendations is unknown. HR ...
Walser Buddy - - 2008
Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have beneficial effects on cardiovascular function. We tested the hypotheses that dietary supplementation with DHA (2 g/day) + EPA (3 g/day) enhances increases in stroke volume (SV) and cardiac output (CO) and decreases in systemic vascular resistance (SVR) during dynamic exercise. Healthy subjects ...
Onorati Paolo - - 2008
Cardiopulmonary exercise test is the gold standard for the identification of the ventilatory compensation point (VCP), an important threshold for exercise training prescription. We hypothesized that changes in the slope of increment in minute ventilation (V'(E)) over heart rate (HR) during incremental exercise can be utilized, as alternative to the ...
Budde Henning - - 2008
Teachers complain about growing concentration deficits and reduced attention in adolescents. Exercise has been shown to positively affect cognitive performance. Due to the neuronal connection between the cerebellum and the frontal cortex, we hypothesized that cognitive performance might be influenced by bilateral coordinative exercise (CE) and that its effect on ...
Savonen Kai P - - 2008
AIMS: The objective is to study whether a heart rate (HR) increase from 40 to 100% of maximal work capacity in the exercise test (HR40-100) independently predicts mortality in men with known or suspected coronary heart disease (CHD). METHODS AND RESULTS: The subjects were 294 men, 42-61 years of age, ...
Hadley David M - - 2008
INTRODUCTION: Reassertion of vagal tone after exercise is an important component in mediating heart rate recovery (HRR), and both vagal tone and HRR have been associated with mortality. HRR is strongly related to the increase in HR from resting to peak exercise. We hypothesized that a score normalized for HR ...
Gregory N G - - 2008
This review highlights some recent developments in our understanding of stress and physical injuries that occur before and during transport to slaughter, during handling at livestock markets, and at the time animals are put-up for slaughter within abattoirs. Stress in pigs during transfer to the stunning point within the abattoir ...
Christou Demetra D - - 2008
A decrease in maximal exercise heart rate (HR(max)) is a key contributor to reductions in aerobic exercise capacity with aging. However, the mechanisms involved are incompletely understood. We sought to gain insight into the respective roles of intrinsic heart rate (HR(int)) and chronotropic beta-adrenergic responsiveness in the reductions in HR(max) ...
Iide Kazuhide - - 2008
The purpose of this study was to investigate the duration of each series of offensive and defensive techniques and the cardiovascular, metabolic, and perceptual responses during 2- and 3-minute bouts of simulated karate sparring. Six young men (age, 18-20 years) and 6 boys (age, 16-17 years) participated in this study. ...
Chandramohan G - - 2008
Predatory efficiency of Diplonychus rusticus (Fabricius) was recorded at different prey density with different salinity ranges. When the salinity level (ppt) was increased, the predation rate of the bug decreased. Fifth nymphal stage showed higher predation in the 2, 4 and 6 ppt levels of salinityin both 1 hr and ...
Turley Kenneth R - - 2008
INTRODUCTION/PURPOSE: This study investigated the effects of three different doses of caffeine on physiological responses to exercise in young children. METHODS: Forty healthy children (20 boys and 20 girls) volunteered for a random, double-blind, counterbalanced study where they received either placebo (PL), 1 mg.kg(-1) (CAF-1), 3 mg.kg(-1) (CAF-3), or 5 ...
Norman Joseph F - - 2008
PURPOSE: The Talk Test is a method for recommending exercise intensity on the basis of the ability of an individual to carry on a conversation during exercise and has been associated with defining the upper recommended limits of exercise intensity for cardiorespiratory training. The purpose of this study was to ...
Mikus C R - - 2009
OBJECTIVE: Cardiovascular drift (CVdrift) is characterised by a continuous, gradual increase in heart rate (HR) after approximately 10 min of moderate-intensity aerobic exercise, despite maintenance of a constant work rate. This has important implications for trials that employ HR to monitor exercise intensity, as reducing work rate in order to ...
Singh Tajinder P - - 2008
PURPOSE: Heart rate (HR) recovery during the first minute after cessation of exercise is predominantly modulated by reactivation of vagal tone. Attenuated 1-min HR recovery is a cardiovascular risk factor in adults. The purpose of this study was to determine predictors of 1-min HR recovery after a maximum-effort exercise test ...
Buchheit M - - 2009
To determine whether a 4-a-side handball (HB) game is an appropriate aerobic stimulus to reach and potentially enhance maximal oxygen uptake (V O(2)max), and whether heart rate (HR) is a valid index of V O(2) during a handball game. Nine skilled players (21.0+/-2.9 yr) underwent a graded maximal aerobic test ...
Adabag A Selcuk AS Division of Biostatistics, School of Public Health, University of Minnesota, Minneapolis, Minnesota, USA. - - 2008
Heart rate (HR) profile during exercise predicts all-cause mortality. However, less is known about its relation to sudden (vs nonsudden) death in asymptomatic people. The relation of exercise HR parameters (HR at rest, target HR achievement, HR increase, and HR recovery) with sudden death, coronary heart disease (CHD) death, myocardial ...
Platisa Mirjana M - - 2008
The origin of heart rate variability (HRV) is largely in parasympathetic activity. The direct influence of sympathetic activity and other control mechanisms, especially at an increased HR, is not well understood. The objectives of the study were to investigate the influence of increasing HR on the properties of heartbeat interval ...
Endo Masako Yamaoka - - 2008
To investigate the regional hemodynamic responses of abdominal arteries at the onset of exercise and to focus on their transient responses, eight female subjects (21-30 yr) performed ergometer cycling exercise at 40 W for 4 min in a semi-supine position. Mean blood velocities (MBVs) in the right renal (RA), superior ...
Lucas Samuel J E - - 2008
The aim of this study was to determine the magnitude and pattern of intensity, and physiological strain, of competitive exercise performed across several days, as in adventure racing. Data were obtained from three teams of four athletes (7 males, 5 females; mean age 36 years, s = 11; cycling .VO(2 ...
Bosquet L - - 2008
OBJECTIVE: A meta-analysis was conducted on the effect of overload training on resting HR, submaximal and maximal exercise HR (HR), and heart rate variability (HRV), to determine whether these measures can be used as valid markers of over-reaching. METHODS: Six databases were searched using relevant terms and strategies. Criteria for ...
Coutts Aaron J - - 2009
The rating of perceived exertion (RPE) could be a practical measure of global exercise intensity in team sports. The purpose of this study was to examine the relationship between heart rate (%HR(peak)) and blood lactate ([BLa(-)]) measures of exercise intensity with each player's RPE during soccer-specific aerobic exercises. Mean individual ...
Lemaître Frédéric - - 2008
BACKGROUND: The diving response includes cardiovascular adjustments known to decrease oxygen uptake and thus prolong apnea duration. As this diving response is in part characterized by a pronounced decrease in heart rate (HR), it is thought to be vagally mediated. METHODS: In five professional breath-hold divers (BHDs) and five less-trained ...
Tabet Jean-Yves - - 2008
OBJECTIVES: To compare the intensity of three exercise training regimens. BACKGROUND: During a cardiac rehabilitation program coronary artery disease (CAD) patients should be trained at an intensity as close as possible to the ventilatory threshold (VT) level. The precise way to obtain this intensity of training during the sessions, however, ...
Maiti Rina - - 2008
A field study was conducted to highlight the occupational risk factors related to building construction activities in India among female workers. These workers were engaged in eight different types of activities and related work parameters were studied in detail. From field environmental parameters, the calculated WBGT was obtained as 30.26+/-1.52 ...
Ichinose Masashi - - 2008
We have previously shown that spontaneous baroreflex-induced changes in heart rate (HR) do not always translate into changes in cardiac output (CO) at rest. We have also shown that heart failure (HF) decreases this linkage between changes in HR and CO. Whether dynamic exercise and muscle metaboreflex activation (via imposed ...
Ya-Ju Chang
Rate of perceived exertion (RPE) is a clinically convenient indicator for monitoring exercise intensity in cardiopulmonary rehabilitation. It might not be sensitive enough for clinicians to determine the patients’ physiological status because its association with the cardiovascular system and local muscle factors is unknown. This study used the electromyographic sensor ...
Theurel J - - 2008
The purpose of the present study was to characterize the physiological demands of postmen during a work day composed of mail sorting (inside work, IW) and cycling distribution (outside work, OW). Two groups of postal workers were constituted according to the geographical profile of their distribution courses: flat profile (FP; ...
Doyle O M - - 2008
The effect of seizures on instantaneous HR (iHR) in 12 neonates is investigated here. HR can be readily extracted from the ECG and can be employed as an additional signal in seizure detection algorithms. The change in instantaneous HR and its correlation with the change in RMS EEG amplitude were ...
Iñesta Claudia - - 2008
Very few studies have analysed heart rate (HR) with regard to music playing, and the scarce evidence available is controversial. The purpose of this study was to analyse the HR response of professional musicians during their real-work activity. Sixty-two voluntary professional musicians (20 women, 42 men), whose ages ranged between ...
Davis W Jackson - - 2008
We compared delayed-onset muscle soreness (DOMS) induced by anaerobic resistance exercises with and without aerobic cardioacceleration before each set, under the rationale that elevated heart rate (HR) may increase blood perfusion in muscles to limit eccentric contraction damage and/or speed muscle recovery. In two identical experiments (20 men, 28 women), ...
Hargens Trent A - - 2008
To evaluate whether cardiovascular responses to maximal exercise testing and recovery are altered with obstructive sleep apnea (OSA) in overweight young adult men. Three sedentary subject groups were recruited: Overweight with OSA (OSA), overweight without OSA (No-OSA), and normal weight without OSA (Control). Presence of OSA was screened via portable ...
Lan Ching - - 2008
Tai Chi Chuan (TC) is a Chinese conditioning exercise and is well-known for its graceful movement. The exercise intensity of TC depends on its training style, posture and duration. Variation in training approaches result in substantial differences in exercise intensity. We have measured heart rate (HR) and oxygen uptake (VO2) ...
Krawczel Peter D - - 2008
The aim of this study was to determine how one group of lambs utilized 2 consecutive rest periods in novel environments with access to food and water that occurred during 22 hr of motor transport. The 18.5 +/- 0.6 kg lambs (n = 15) were transported for 8 hr and ...
Sinclair Wade H - - 2009
A paucity of empirical research exists into surf lifesaving competition from which coaches and athletes may formulate training and recovery strategies. Seventeen (male=9; female=8) high-performance surf lifesavers (21.2+/-3.9 years) contested multiple rounds of team and individual events at a 2-day surf lifesaving competition. Individual events consisted of the multi-discipline ironman ...
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