OBJECTIVES To determine in this pilot study whether aerobic exercise affects phenylacetic acid concentration in the urine. METHODS Twenty healthy men provided 24 hour urine samples on two consecutive days for the determination of phenylacetic acid levels. Before and during day 1, subjects refrained from physical activity; on day 2 subjects ran on a treadmill at 70% of their maximal heart rate...

Twelve male patients, with effort angina and a history of cold intolerance, performed brief submaximal exercise bicycle tests with separation of inspiratory and room air. In one test, the patients exercised in a normal room (20°C), breathing either normal or very cold air (-35°C). In another test, environmental air \vas either normal or -10°C, and four combinations of inspiratory and room air w...

The purpose of this study was to examine the physiological characteristics of an elite centenarian cyclist who, at 101 yr old, established the 1-h cycling record for individuals ≥100 yr old (24.25 km) and to determine the physiological factors associated with his performance improvement 2 yr later at 103 yr old (26.92 km; +11%). Before each record, he performed an incremental test on a cycling ...

introduction: good functional capacity has a high negative predictive value (npv) in patients with known or suspected coronary artery disease (cad) similar to a normal gated myocardial perfusion imaging (gmpi). aim of this study was to evaluate npv of functional capacity during treadmill exercise in patients with normal gmpi in pakistani population. methods: this was a prospective study which ...

OBJECTIVE To assess the consciousness level, pulmonary and hemodynamic effects of orthostatic position in intensive care patients. METHODS This study was conducted from April 2008 to July 2009 in the Adult Intensive Care Unit, Hospital das Clínicas, Universidade Estadual de Campinas, São Paulo, Brazil. Fifteen patients were included who were mechanically ventilated for more than seven days an...

Physical exercise is associated with parasympathetic withdrawal and increased sympathetic activity resulting in heart rate increase. The rate of post-exercise cardiodeceleration is used as an index of cardiac vagal reactivation. Analysis of heart rate variability (HRV) and complexity can provide useful information about autonomic control of the cardiovascular system. The aim of the present stud...

Early- and intermediate-term results of the arterial switch operation for D-transposition of the great arteries (D-TGA) are encouraging. However, questions remain about the long-term outcome for these patients, especially with regard to exercise performance. Preliminary studies have demonstrated normal endurance time on treadmills. However, data regarding aerobic capacity and cardiopulmonary fu...

The relationship between heart rate (HR) during exercise and exercise capacity in patients with heart failure due to left ventricular systolic dysfunction remains unclear. The accepted diagnostic criterion for chronotropic incompetence (CI), a maximum agepredicted heart rate (MA-PHR) 85%, is seen in 50% of patients with severe heart failure on contemporary medical therapy (1). Whether the lesse...

BACKGROUND Current guidelines recommend that caffeinated products should be avoided for at least 12 hours prior to regadenoson administration. We intended to examine the effect of caffeine consumption and of timing of last dose on hemodynamic effects after regadenoson administration for cardiac stress testing. METHODS 332 subjects undergoing regadenoson stress testing were enrolled. Baseline ...