Search Results
Results 351 - 400 of 1266
< 3 4 5 6 7 8 9 10 11 12 13 >
Ciammaichella R A - - 2000
Previous findings of a narcosis-induced reduction in heat production during cold water immersion, as reflected in oxygen uptake (VO2), have been attributed to the attenuation of the shivering response. The possibility of reduced oxygen utilization (VO2) by the muscles could not, however, be excluded. Accordingly, the present study tested the ...
Roy B D - - 2000
To examine the role of a reduction in plasma volume (PV) on the cardiovascular and thermoregulatory responses to submaximal exercise, ten untrained males (VO2 peak = 3.96 +/- 0.14 L x min(-1); mean +/- SE) performed 60 min of cycle exercise at -61% of VO2 peak while on a diuretic ...
Myers J - - 2000
Historically, the protocol used for exercise testing has been based on tradition, convenience or both. In the 1990s, a considerable amount of research has focused on the effect of the exercise protocol on test performance, including exercise tolerance, diagnostic accuracy, gas exchange patterns and the accuracy with which oxygen uptake ...
Geor R J - - 2000
OBJECTIVE: To compare effects of low and high intensity warm-up exercise on oxygen consumption (VO2) and carbon dioxide production (VCO2) in horses. ANIMALS: 6 moderately conditioned adult Standard-breds. PROCEDURES: Horses ran for 2 minutes at 115% of maximum oxygen consumption (VO2max), 5 minutes after each of the following periods: no ...
Reiser M - - 2000
The aim of this study was to test the transferability of workload measurements between three different types of bicycle ergometer. Two common ergometers (Lode Excalibur and Avantronic Cyclus 2) were compared with a powermeter (Schoberer SRM system) that enables the measurement of power output during road cycling. Twelve well-trained subjects ...
Rodríguez F A - - 2000
BACKGROUND: This study compared the cardiorespiratory response of trained swimmers to 400-m unimpeded front crawl swimming (SW), treadmill running (TR) and ergometer cycling (EC) maximal exercise tests, and evaluated the validity and specificity of a method to measure maximal aerobic power in swimming. METHODS: Two series of experiments were conducted. ...
Cunningham D A - - 2000
The oxygen uptake response to moderate-intensity exercise (i.e. < anaerobic threshold (an)) has been characterised with a gain (i.e. response amplitude per increment of work rate) and time constant that do not vary appreciably at different work rates or between the on- and off-transients. Above an, the response becomes more ...
Watts P B - - 2000
The objectives of this study were to 1) continuously assess oxygen uptake during and after difficult sport rock climbing and 2) to evaluate the effects of active versus passive recovery on post-climbing blood lactate and hand grip strength. Fifteen expert rock climbers attempted to climb (i.e., red point lead) a ...
Dasgupta P K - - 2000
Selected short distance runners, middle distance runners and long distance runners were subjected to graded exercise on a treadmill. The maximum aerobic power (VO2 max) and other indices related to oxygen transport system viz. heart rate, ventilation volume, breathing reserve, dyspnoeic index, O2 pulse and RQ were recorded at respective ...
Bogaard H J - - 2000
PURPOSE: Many attempts have been made to predict peak VO2 from data obtained at rest or submaximal exercise. Predictive submaximal tests using the heart rate (HR) response have limited accuracy. Some tests incorporate submaximal gas exchange data, but a predictive test without gas exchange measurements would be of benefit. Addition ...
Yano T - - 2000
BACKGROUND: The purpose of the present study was to examine the kinetics of oxygen uptake (VO2) during decremental ramp exercises after incremental ramp exercise above the anaerobic threshold. METHODS: Triangle exercise consisting of incremental and decremental exercises, and trapezoid exercise in which a constant load was inserted between incremental and ...
Puente-Maestu L - - 2000
The effects of two 8 week programmes of reconditioning in chronic obstructive pulmonary disease (COPD) patients were studied. Forty one subjects (mean+/-SD) 644.5) yrs; forced expiratory volume in one second (FEV1) 1.09+/-0.16 L; 40.6+/-6.2% predicted were randomly assigned either to supervised training on a treadmill, 4 days x week(-1) (group ...
Bernard O - - 2000
PURPOSE: The theoretical velocity associated with VO2max (vVO2max) defined by Daniels (1985) is extrapolated from the submaximal VO2-velocity relationship. VO2 is generally determined by assuming that the aerobic response reacts like a linear first-order system at the beginning of square-wave exercise with a steady-state reached by the 4th minute. However, ...
Usaj A - - 2000
The linear relationship between oxygen consumption (VO2) and exercise intensity is a well established phenomenon observed during incremental exercise. Recently, a non-linear increase in VO2 has been reported by Zoladz et al., who used a relatively complicated method to describe the phenomenon. In this study, we tried to ascertain whether ...
Massin M M - - 2000
MATERIAL AND METHODS: Gas exchange and heart rate (HR) kinetics were investigated in 20 patients with cystic fibrosis (CF) by using a pseudorandom binary sequence (PRBS)-technique. Electrocardiogram was continuously recorded, and VO2, VCO2 and ventilation/min (VE) responses to a multifrequent input signal were measured by means of breath-by-breath analysis. Lag ...
Wiesinger G F - - 2000
OBJECTIVE: Assessment of myositis patients has relied on symptoms, strength testing, and serum muscle enzyme activity. Recently, functional assessments and evaluation of strength by dynamometry and of disease activity by magnetic resonance imaging have also been added. Aerobic testing in selected patients has been considered useful. DESIGN: Case-control study. SETTING: ...
Cheuvront S N - - 1999
Claims that ENDUROX enhances performance by altering metabolic responses to exercise were tested. In a double-blind crossover design, 10 male subjects were randomly assigned to consume 400 mg of placebo or 800 mg ENDUROX for 7 days. Cycle ergometry was performed for 30 minutes at 25%, followed by 10 min ...
Kawaguchi K - - 1999
The purpose of this study was to develop an oxygen consumption (VO2) measurement for adult hemiplegic patients during an incremental exercise arm-cranking test. Fifty-five adult hemiplegic patients performed a three-stage arm-cranking exercise test while VO2 was measured. The control group consisted of thirteen healthy elderly persons who performed a similar ...
Buckley J P - - 1999
PURPOSE: The aim of this study was to compare the cardio-respiratory differences between rowing ergometry and treadmill exercise in beta-blocked men participating in exercise rehabilitation soon after myocardial infarction (postMI). METHODS: Eleven males all receiving beta-blockade medication were measured for oxygen consumption (VO2), respiratory exchange ratio (RER), and rating of ...
Agostoni P G - - 1999
It gets more and more frequent to use oxygen consumption (VO2) to evaluate exercise capacity and response to treatment in heart failure patients. The amount of VO2 is due to ventilation, oxygen transport and muscle activity. No one of these single steps can define by itself VO2, but all these ...
Skinner J S - - 1999
PURPOSE: The reproducibility of responses to maximal cycle ergometer testing was determined using data from the HERITAGE Family study at four Clinical Centers in the United States and Canada. METHODS: Reproducibility was determined from maximal exercise test data obtained a) on 2 d in a sample of 390 subjects (198 ...
Keyser R E - - 1999
OBJECTIVE: To determine if a single-stage, submaximal fatigue test on a wheelchair ergometer would result in higher than expected energy expenditure. DESIGN: An experimental survey design contrasting physiologic responses during peak graded exercise tests and fatigue tests. SETTING: A rehabilitation science laboratory that included a prototypical wheelchair ergometer, open-circuit spirometry ...
Brandenburg S L - - 1999
OBJECTIVE: Women with uncomplicated type 2 diabetes have both a decreased maximal oxygen consumption (VO2max) and slowed oxygen uptake (VO2) kinetics at the onset of exercise compared with nondiabetic women. These abnormalities are seen not only at maximal workloads, but also at the onset of low-level exercise. To evaluate the ...
Carter R - - 1999
Ankylosing spondylitis (AS) has been shown to produce exercise limitation and breathlessness. The purpose of this study was to investigate factors which may be responsible for limiting aerobic capacity in patients with AS. Twenty patients with no other cardio-respiratory disease performed integrative cardiopulmonary exercise testing (CPET). The results were compared ...
Christmass M A - - 1999
In this study we compared substrate oxidation and muscle oxygen availability during sustained intermittent intense and continuous submaximal exercise with similar overall (i.e. work and recovery) oxygen consumption (VO2). Physically active subjects (n = 7) completed 90 min of an intermittent intense (12 s work:18 s recovery) and a continuous ...
Billat V L - - 1999
The purpose of this study was to compare the effect of two different types of cyclic severe exercise (running and cycling) on the VO2 slow component. Moreover we examined the influence of cadence of exercise (freely chosen [FF] vs. low frequency [LF]) on the hypothesis that: 1) a stride frequency ...
Mullis R - - 1999
OBJECTIVES: To establish a simple, valid, and acceptable method of predicting peak oxygen uptake (VO2peak) in patients with chronic fatigue syndrome (CFS), which could provide a basis for subsequent exercise prescription at an appropriate intensity as part of a clinical rehabilitation programme. METHODS: A total of 130 patients who met ...
Baba R - - 1999
BACKGROUND: To elucidate the intertest agreement of the oxygen uptake efficiency slope (OUES) in comparison with those of the maximal oxygen uptake (VO2max) and the ventilatory anaerobic threshold (VAT). METHODS: Experimental design: A comparative study. Setting: Institutional practice. A total of 19 healthy volunteers underwent two sessions of maximal exercise ...
Jones A M - - 1999
PURPOSE: The purpose of this study was to assess the relationship between pulmonary VO2 and running speed over a range of exercise intensities. During constant-load cycle exercise above the lactate threshold (Tlac), it has been shown that VO2 does not attain a steady state within 3 min but continues to ...
Jones A M - - 1999
The mechanisms responsible for the oxygen uptake (VO2) slow component during high-intensity exercise have yet to be established. In order to explore the possibility that the VO2 slow component is related to the muscle contraction regimen used, we examined the pulmonary VO2 kinetics during constant-load treadmill and cycle exercise at ...
McKone E F - - 1999
OBJECTIVES: Exercise testing in patients with cystic fibrosis (CF) has become an important tool in assessing disease severity and predicting overall outcome. The reproducibility of maximal exercise testing was examined in adult subjects with stable CF. METHODS: Nine subjects with CF underwent a total of three maximal exercise tests carried ...
Bell C - - 1999
Cross-sectional studies have compared the oxygen uptake (VO2) kinetics during the on-transient of moderate intensity exercise in older and younger adults. The slower values in the older adults may have been due to an age-related reduction in the capacity for O2 transport or alternatively a reduced intramuscular oxidative capacity. We ...
King G A - - 1999
The purpose of this study was to test the validity of the Aerosport KB1-C portable metabolic measurement system against the criterion Douglas bag method. During cycle ergometry, simultaneous measurements of minute ventilation (VE), oxygen consumption (VO2), and carbon dioxide production (VCO2) were made at rest and at power outputs of ...
Girardis M - - 1999
A model of the metabolic internal power (Eint) during cycling, which includes the gravity acceleration (ag) as a variable, is presented. This model predicts that Eint is minimal in microgravity (0 g; g=9. 81 m s-2), and increases linearly with ag, whence the hypothesis that the oxygen uptake (VO2) during ...
Hayashi N - - 1999
We investigated the effect of central hypervolaemia during water immersion up to the xiphoid process on the oxygen uptake (VO2) and heart rate (HR) response to arm cranking. Seven men performed a 6-min arm-cranking exercise at an intensity requiring a VO2 at 80% ventilatory threshold both in air [C trial, ...
Ahmaidi S - - 1999
PURPOSE: This study tests the reliability of a new device for assessing the oxygen consumption of the respiratory muscles (VO2 resp.). METHODS: Fourteen healthy male volunteers participated in the study. The device consists of an expandable external ventilatory dead space created with pieces of plastic tubing and a spirometer filled ...
Shimizu N - - 1999
The effect of exercise intensity on gas exchange kinetics was investigated during exercise and recovery, as well as the relationship between the kinetics during exercise and recovery. Twenty-three patients with a history of anterior myocardial infarction performed low-intensity (38.7+/-8.3 W) and high-intensity (68.8+/-15.0 W) exercise for 6 min. The time ...
McInnis K J - - 1999
Oxygen uptake (VO2) during treadmill exercise is directly related to the speed and grade, as well as the participant's body weight. To determine whether body composition also affects VO2 (ml.kg-1.min-1) during exercise, we studied 14 male body builders (M weight = 99 kg, SD = 7; M height = 180 ...
Moran D S - - 1999
A physiological strain index (PSI) based on rectal temperature (Tre) and heart rate (HR) was recently suggested to evaluate exercise-heat stress. The purpose of this study was to evaluate PSI for gender differences under various combinations of exercise intensity and climate. Two groups of eight men each were formed according ...
Stanley R K - - 1999
OBJECTIVE: This study assessed and compared the cardiopulmonary function of individuals with Parkinson's disease (PD) with that of healthy normals (HN) in order to provide health professionals with more thorough information about the problems associated with PD. METHODS: 20 men (PD = 13, HN = 7; mean age 64 and ...
Crystal G J - - 1999
The effects of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) and the NO donor sodium nitroprusside (SNP) on whole body O2 consumption (VO2) were assessed in 16 dogs anesthetized with fentanyl or isoflurane. Cardiac output (CO) and mean arterial pressure (MAP) were measured with standard methods and were used ...
Friedlander A L - - 1999
We examined the effects of exercise intensity and a 10-wk cycle ergometer training program [5 days/wk, 1 h, 75% peak oxygen consumption (VO2 peak)] on plasma free fatty acid (FFA) flux, total fat oxidation, and whole body lipolysis in healthy male subjects (n = 10; age = 25.6 +/- 1.0 ...
Lavie C J - - 1999
Using cardiopulmonary stress testing in 76 lean and 99 obese coronary patients, we demonstrated significant improvements in both groups for anaerobic threshold, peak aerobic capacity (VO2), peak VO2 corrected for lean body mass, and work efficiency. Although anaerobic threshold and peak VO2 are adequate to describe exercise capacity in lean ...
Lewalter T - - 1999
The oxygen uptake to work rate (VO2/WR) relationship observed throughout peak exercise testing is already being applied for rate adaptive pacemaker programming. However, the detailed curve design of VO2/WR with respect to the anaerobic threshold (AT) has not yet been investigated. It was the purpose of this study to determine ...
Xu F - - 1999
The characteristics of oxygen uptake (VO2) kinetics differ with exercise intensity. When exercise is performed at a given work rate which is below lactate threshold (LT), VO2 increases exponentially to a steady-state level. Neither the slope of the increase in VO2 with respect to work rate nor the time constant ...
Parolari A - - 1999
BACKGROUND: This study was undertaken to investigate the relations between whole body oxygen consumption (VO2), oxygen delivery (DO2), and hemodynamic variables during cardiopulmonary bypass. METHODS: One hundred one patients were studied during cooling, hypothermia, and rewarming. Oxygen consumption, DO2, hemodynamics, and DO2crit were measured at these times. RESULTS: There was ...
Poulin M J - - 1999
This study examined the consistency between three indexes of cerebral blood flow (CBF) obtained by using transcranial Doppler ultrasound in eight human volunteers. Each subject undertook three sessions of graded exercise, consisting of 6 min of rest, 6 min at 20% of maximal oxygen uptake (VO2 max), 6 min at ...
Atwood J E - - 1999
BACKGROUND: beta-blockade controls the ventricular response to exercise in chronic atrial fibrillation (AF), but the effects of beta-blockers on exercise capacity in AF have been debated. METHODS: Twelve men with AF (65+/-8 years) participated in a randomized, double-blind, placebo-controlled study of betaxolol (20 mg daily). Patients underwent maximal exercise testing ...
Langsetmo I - - 1999
At the onset of exercise, horses exhibit O2 uptake (VO2) kinetics that are qualitatively similar to those of humans. In humans, there is a marked dissymmetry between on- and off-kinetics for VO2. This investigation sought to formally characterize the off-transient (recovery) VO2 kinetics in the horse within the moderate (M), ...
Dominick K L - - 1999
PURPOSE: To compare three equations developed to predict VO2 among patients diagnosed with one of two chronic diseases: essential hypertension (HTN), and fibromyalgia (FM). The equations included the American College of Sports Medicine (ACSM) equation, the FAST equation developed from the Fitness and Arthritis in Seniors Trial (FAST), and an ...
< 3 4 5 6 7 8 9 10 11 12 13 >