BACKGROUND The role of the perception of breathing effort in the regulation of performance of maximal exercise remains unclear. AIMS To determine whether the perceived effort of ventilation is altered through substituting a less dense gas for normal ambient air and whether this substitution affects performance of maximal incremental exercise in trained athletes. METHODS Eight highly trained...

BACKGROUND/AIM Although it has been hypothesized that muscle metabolism and fatigability could be impaired in sickle cell patients, no study has addressed this issue. METHODS We compared muscle metabolism and function (muscle microvascular oxygenation, microvascular blood flow, muscle oxygen consumption and muscle microvascular oxygenation variability, which reflects vasomotion activity, maxi...

906 Physiology and Management of Shock (Bressak, Raffin) PHYSIoLoGIC BACKGROUND A reasonable, unifying definition of shock at the cellular level is inadequate oxygen consumption by the cell for its metabolic needs. The negative consequence is the accumulation of an oxygen debt with eventual cellular dysfunction and death. Inadequate oxygen consumption (shock) can result from the following: (1) ...

The length-tension and length-oxygen consumption rate relationships were studied in bovine mesenteric vein at 37 degrees C. The absence of spontaneous mechanical activity permits straightforward interpretation in terms of active (smooth muscle) and passive components of the vein wall. Longitudinal loops, the predominant smooth muscle component being oriented in the longitudinal (axial) directio...

BACKGROUND The present study was designed to evaluate load carriage performance at extremely high altitudes with different loads and walking speeds in terms of physiological evaluation. The degree of maximum oxygen consumption changes at high altitudes was also examined. METHODS Twelve Indian Army soldiers were acclimatized at altitudes of 3,505 m and 4,300 m. They walked for 10 minutes on a ...

OBJECTIVES A recent editorial in Medicine and Science in Sports and Exercise concludes that the study of Hawkins and colleagues confirms "beyond any doubt the proposition of Hill and Lupton". It is not clear which of Hill and Lupton's propositions have been proved "beyond any doubt". METHODS A review of all the relevant publications of A V Hill and his colleagues. RESULTS Hill and Lupton be...

SYNOPSIS. TWO processes strongly influence the distribution of oxygen within egg masses and cells: the supply of oxygen by diffusion and the consumption of oxygen by embryos and mitochondria. These processes are differentially sensitive to temperature. The diffusion coefficient of oxygen depends only weakly on temperature, having a Ql0 of approximately 1.4. In contrast, the consumption of oxyge...

objectives the aim of this study was to investigate the relation between respiratory muscle strength and the severity of chf, and the influence of respiratory muscle strength on abnormal ventilation during exercise in chf patients. conclusions respiratory muscle strength is related to the severity of chf, and associated with rapid and shallow ventilation or excessive ventilation during exercise...

Boosting nitric oxide production during exercise by various means has been found to improve exercise performance. We investigated the effects of a nitric oxide releasing lozenge with added caffeine (70 mg) on oxygen consumption during steady-state exercise and cycling time trial performance using a double-blinded randomized, crossover experimental design. 15 moderately trained cyclists (7 femal...