PURPOSE: Ratings of perceived exertion (RPE) are widely used for monitoring individuals during graded exercise testing. Studies of the reliability of RPEs across various exercise conditions have produced mixed results. The purpose of this study was to assess the reliability of RPEs during graded exercise testing by comparing the perceptual-physiological ...

Minute ventilation (VE) controlled rate adaptive pacemakers determine the paced rate increase during exercise by measuring changes in transthoracic impedance that have been shown to correlate well with VE. To determine the normal coupling of heart rate (HR) to VE this relationship was evaluated in 30 younger and 25 older, ...

The purpose of this study was to investigate reliability, handling characteristics and complication rate of the CAMINO-ICP-monitor-system in clinical routine. In a case controlled study 82 patients with intracranial pathology necessitating ICP-monitoring received either a ventricular or a parenchymal CAMINO-device. Clinical assessment of curve shape and apparent reliability of the ...

This study hypothesized that changes in static shoulder loading while using aerobars during submaximal cycle ergometry would elicit a combined static and dynamic pressor response. Seven trained cyclists (mean +/- SD: 22 +/- 3 years, 77 +/- 12 kg, 1.8 +/- 1.1 m) rode a modified Monark cycle ergometer at ...

To investigate the hypothesis that an increase in plasma volume (PV) is obligatory in reducing the cardiovascular drift that is associated with prolonged exercise following training, a plasma expander (Macrodex) was used to acutely elevate PV. Eight untrained volunteers [maximal oxygen consumption; VO2max 45.2 (2.2) ml x kg(-1) x min(-1), ...

The R-R interval varies with the cycles of respiration. The response of the variability in the R-R interval with respiration was examined during sinusoidal cycle exercise in 12 healthy young male subjects. Work rate varied sinusoidally between 30 W and 60% maximal oxygen uptake for an 8-min period. The higher ...

Whereas with advancing age, peak heart rate (HR) and cardiac index (CI) are clearly reduced, peak stroke index (SI) may decrease, remain constant or even increase. The aim of this study was to describe the patterns of HR, SI, CI, arteriovenous difference in oxygen concentration (Ca-vO2), mean arterial pressure (MAP), ...

To assess if propranolol influences orthostatic intolerance induced by prolonged bed rest (BR), a lower body negative pressure test (LBNP) and left ventricular (LV) echocardiography before and during -40mmHg of LBNP were performed with and without intravenous propranolol administration (0.04mg/kg) in 9 healthy volunteers (mean age: 21 years) before and ...

The purpose of the present study was to compare arterial pressure (AP) and heart rate (HR) responses to submaximal isokinetic, isotonic and isometric exercises currently employed in physical rehabilitation therapy in terms of both magnitude and time-course. To this aim AP and HR were continuously and noninvasively measured in ten ...

Five Standardbred trotters performed treadmill exercise with incrementally increasing trotting velocities for 2 min intervals in three different tests until fatigue. Each test was performed with draught loads of either 10, 20 or 30 kilopond (kp). Each trotting interval was followed by 2 min periods at a walk without draught ...

We hypothesized that the carotid-cardiac baroreflex becomes slowed in conditions with increased sympathetic activity. Changes in heart rate (HR) and blood pressure in response to 10-s trains of 50-mmHg pulses of neck suction (NS) were studied in six male subjects during supine rest, upright rest, isometric arm exercise at 30% ...

Short-lasting neck suction (NS) is a common method to assess the carotid-cardiac baroreflex, and NS is usually applied during apnea to avoid breath-synchronous variations of heart rate (HR) and blood pressure. We hypothesized that the apnea might provoke cardiovascular effects that could confound the HR and blood pressure responses to ...

To evaluate whether occasional strong physical activity at moderate altitude for several consecutive days is acceptable in untrained middle-aged people, 10 men (age range, 46-59 years) underwent physical examinations before (control day, D0), during (D1-D8), and after 1 wk of leisure alpine skiing. With respect to D0, the resting concentration ...

The Borg Ratings of Perceived Exertion scale (RPE) has been shown to be a valuable tool for prescribing exercise; however, use of RPE-based exercise prescriptions in field settings has often been problematic because RPE data derived from maximal exercise testing are needed. We describe a simple method for obtaining target ...

PURPOSE: The present study was aimed at evaluating electrocardiographic (ECG) changes associated with partial epileptic seizures without seizure activity secondarily generalized. METHODS: We assessed heart rate (HR) changes occurring during 100 partial epileptic seizures, as recorded by ambulatory EEG-ECG in 50 outpatients. Consecutive R-R intervals were measured for the 30 ...

Recent reports have suggested that minor arterial lesions can be responsible for claudication in athletes occurring only during maximal exercise. Ankle to arm index measurements (AAI) prove the arterial origin of this claudication, but little is known about the normal response of AAI to maximal exercise. Therefore, we studied the ...

The purpose of this study was to examine psychological affect at different ratings of perceived exertion (RPE) in 15 high- and 15 low-active women. Both groups performed three steady-state exercise bouts on a cycle ergometer at RPEs 9, 13, and 17 and reported their affect in the last 20 sec. ...

The reactive sensitivities of T-wave amplitude (TWA), pulse-transit time (PTT) and heart rate (HR) were examined in response to psychological, physiological, and combined challenges. In one experiment, 20 subjects performed 1-min arithmetic and combined arithmetic-with-cycling tasks, with HR and TWA being measured. The former showed significant reactive sensitivity, but TWA ...

Short-track speed skating involves pack-style racing where five to seven skaters may be on the ice at once. Since average speed for a 3000-m event may exceed 35 km.h-1, drafting may be beneficial. However, the short (111 m) oval track could limit effective drafting space, and high forces required in ...

OBJECTIVE: To determine the ability of a new electrochemical sensor to determine heparin levels in whole blood and to correlate the heparin levels as determined by this heparin-responsive sensor (HRS) with heparin levels as determined by the Hepcon assay system (Medtronic Hemotec, Parker, CO). DESIGN: Methods comparison study. SETTING: A ...

Limited information is available concerning the exercise response during handball (HB) singles match-play. Also, few studies exist that have examined VO2 peak and body composition of HB players. The purpose of this study was to examine the heart rate (HR) response during match play and peak physiologic responses and relative ...

We have studied 45 patients, aged 60-95 yr, receiving subarachnoid block for neck of femur fractures. Patient received either colloid (polygeline, Haemaccel) 8 ml kg-1 (n = 15), metaraminol 5 micrograms kg-1 and 1.7 micrograms kg-1 min-1 (n = 15) or a combination of both treatments to maintain systolic arterial ...

Examination of blood pressure (BP) and heart rate (HR) measurements at rest and during exercise in samples of USA and Russian middle-aged men and women show significant differences between countries for both genders. Russian men had higher resting systolic blood pressure (SBP) than USA men but lower SBP at both ...

The purposes of this study were to assess if women 60 to 75 years of age perceived a series of exercise intensities differently from selected intensities in that series and to determine if a particular intensity was perceived more reliably. Twenty-four women (65 +/- 3.8 yr) completed a walking VO2max ...

We examined whether ratings of perceived exertion (RPE) observed during an incremental (response) protocol could be used to produce target blood [HLa] of 2.5 mM and 4.0 mM during a 30-min treadmill run at a constant RPE. RPE (15.3, 17.6, 19.1), oxygen uptake (VO2) (3.31, 3.96, 4.00 l.min-1), velocity (V) ...

Nordic skiers place great emphasis on upper body endurance. Therefore, the purpose of this study was to compare oxygen uptake (VO2), minute ventilation (VE), tidal volume (VT), breath frequency (fB), heart rate (HR), and ventilatory anaerobic threshold (Tvan) responses to upper body classical poling (CP) and double poling (DP). Sixteen ...

INTRODUCTION: We tested the hypothesis that the elevated peak heart rate (HR) response to maximal exercise following microgravity exposure is associated with increased plasma levels of catecholamines. METHODS: To do this, plasma norepinephrine (NE) and epinephrine (E) were measured in venous blood samples obtained from 7 subjects before and immediately ...

1. Static exercise elicits increases in arterial blood pressure and heart rate (HR) in humans and conscious animals. In this study, the effects of intracerebroventricular (I.C.V.) administration of clonidine, an alpha 2-adrenergic agonist, on these cardiovascular responses were investigated using conscious cats. Four cats were operantly trained to extend a ...

OBJECTIVE: Exercise training intensity for aerobic conditioning is typically established by heart rate (HR), oxygen uptake, or rating of perceived exertion (RPE). Recent research, however, suggests that the optimal training intensity may be more appropriately established from measurements of blood lactate concentration ([La]). This study examined the relationships among three ...

OBJECTIVE: Conconi et al. proposed that the point where heart rate departed from linearity in an incremental exercise test was a good indicator of the anaerobic threshold. However, the heart rate deflection points (HRDPs) can not be determined in many subjects. The aim of this study was to determine the ...

The purpose of this investigation was to quantify the difference in energy expenditure between traditional cycling handlebars and aero-bars during outdoor submaximal cycling. Eleven trained cyclists (age = 29.3 +/- 1.9 years, weight = 69.4 +/- 3.8 kg, VO2max = 58.1 +/- 2.0 ml.kg-1.min-1) were randomly assigned a sequence of ...

An experiment has been designed to compare two ways of load moving: pushing with a bar or hauling with a pelvic belt, against the same resistances, at the same speeds. This study has been carried out in the laboratory on a treadmill, using two groups: 15 healthy sedentary men and ...

The purpose of this study was to examine the validity of the use of ratings of perceived exertion (RPE) to estimate and regulate exercise intensity during rowing ergometry. Nine competitive male rowers [mean age 28.6 years, (SD 6.3)] completed two rowing trials on an ergometer. The first trial (estimation) consisted ...

According to the Rosenblueth-Simeone model, the heart rate (HR) is proportional to the sympathovagal balance. The individual proportionality constant is the intrinsic HR, which can be determined only invasively. The percentage low-frequency spectral HR variability power, relative to the low- plus high-frequency spectral power (%LF) has been raised as a ...

The purpose of this study was to determine the effect of passive leg cycle exercise (PLE) on cardiovascular and respiratory responses in people with spinal cord injuries (PSCI). Eight PSCI with lesions from T8 to L1 and five control subjects (CS) performed PLE at pedalling frequencies of 20 or 40 ...

The effects of acute inhalation of hypoxic gas mixtures on minute ventilation (VE), respiratory frequency (fR) and heart rate (HR) were studied in healthy subjects executing constant-load 100 W and 150 W hindlimb exercises (protocol 1) or unloaded (0 W) cycling (protocol 2). Attention was focussed on early changes in ...

The effects of glycerol ingestion (GEH) on hydration and subsequent cycle ergometer submaximal load exercise were examined in well conditioned subjects. We hypothesized that GEH would reduce physiologic strain and increase endurance. The purpose of Study I (n = 11) was to determine if pre-exercise GEH (1.2 gm/kg glycerol in ...

It has been shown that muscle protein synthetic rate (MPS) is elevated in humans by 50% at 4 hrs following a bout of heavy resistance training, and by 109% at 24 hrs following training. This study further examined the time course for elevated muscle protein synthesis by examining its rate ...

BACKGROUND: We previously showed that exercise capacity in patients with hypertrophic cardiomyopathy (HCM) is related to peak exercise cardiac output. Cardiac output augmentation during exercise is normally dependent on heart rate (HR) response and stroke volume (SV) augmentation by increased left ventricular end-diastolic volume and/or increased contractility. We hypothesized that ...

We investigated the physiologic heart rate (HR) to work rate (WR) relation throughout peak exercise in normal subjects as a guideline for rate-adaptive pacemaker slope programming. The study group consisted of 41 middle-aged subjects (22 men and 19 women) without evidence of cardiopulmonary disease. Peak-exercise stress tests were performed on ...

The purpose of this study was to assess hemodynamic responses to lower body negative pressure (LBNP) to -45 torr with selective cardiac parasympathetic (using atropine sulphate), sympathetic efferent (using metoprolol tartrate), and combined (atropine+metoprolol) blockade prior to and following 8 months of endurance exercise training in eight young men. Training ...

We tested the hypothesis that the reflex inhibition of heart rate (HR) during mechanical (acute bolus injection of 0.5% and 2% of estimated blood volume) and chemical (phenylbiguanide, PBG, 2.5 and 5 micrograms.kg-1) stimulation of cardiopulmonary receptors would be enhanced during exercise. Rats were instrumented with arterial and venous catheters. ...

Stimulation of cardiopulmonary vagal C fibers with phenyl biguanide (PBG) reflexly inhibits locomotion in addition to causing depression of blood pressure (BP), heart rate (HR), and respiration in cats and rats. We investigated whether PBG caused somatomotor inhibition during exercise in the rabbit, a species in which it is known ...

We tested the hypothesis that one bout of maximal exercise performed 24 h before reambulation from 16 days of 6 degrees head-down tilt (HDT) could increase integrated baroreflex sensitivity. Isolated carotid-cardiac and integrated baroreflex function was assessed in seven subjects before and after two periods of HDT separated by 11 ...

This investigation examined using heart rate (HR), central rating of perceived exertion (C-RPE) and peripheral rating of perceived exertion (P-RPE) values obtained during a graded exercise test (GXT) for monitoring intensity during a 5000 m field run. Ten trained runners performed a GXT to determine HR, C-RPE and P-RPE values ...

The relationships between perceived exertion and the physiological variables oxygen uptake (VO2), heart rate (HR) and blood lactate concentration (HLa) were studied in tethered swimming. Seven male and ten female subjects swam at five submaximal intensities. The degree of perceived exertion was measured both on the category scale (RPE) and ...

The study of simultaneous variations in heart rate (HR) and systemic blood pressure is of great interest in ergometric practice complementing the analysis of the ST segment by ECG. This paper examines data proceeding from 500 consecutive, normal, exercise stress tests with the aim of offering reference values on the ...

The purpose of this study was to compare the time course of the bradycardic and hypotensive effects of esmolol. Ten patients undergoing craniotomy requiring hypotension were anesthetized with nitrous oxide and isoflurane. During steady state anesthesia, the response to an infusion of esmolol 500 micrograms.kg-1.min-1 for 90 s followed by ...

The purpose of this study was to examine the cardiovascular responses of sprinters and distance runners to isometric (IE) and dynamic exercise (DE). Normotensive males were selected and grouped according to prior running performance: sprinter (N = 6) or distance runner (N = 6). Each subject completed an incremental DE ...

The objective of rate adaptive pacemakers that measure minute ventilation by transthoracic impedance is to simulate the physiological relationship of the sensed signal to the sinus node response during exercise, thus achieving an appropriate matching of heart rate with patient effort. The purpose of this study was to determine the ...