To delineate the effects of true aging, undetected heart disease and deconditioning on heart rate, we performed 24-hour ambulatory electrocardiography and maximal exercise stress test on 101 subjects with normal hearts. The maximal heart rate recorded was 180 beats/min; the minimum was 35 beats/min. A distinct diurnal pattern was observed. With increasing age, a decrease of the maximal heart ra...

The purpose of this study was to develop a valid prediction of maximal oxygen uptake from data collected during a submaximum bench stepping test among children ages 8-12 years. Twentyseven active subjects (16 male and 11 female), weight 36.1 kg, height 144.4 cm and VO2 47.4 ± 7.9 ml/kg/min participated. Subjects completed a maximal oxygen consumption test with analysis of expired air and a subm...

Background: The primary purpose of this investigation was to determine the differences in resting heart rate variability and heart rate recovery between norm-referenced aerobic fitness groupings, independent of body composition, in Black men. Additionally, we sought to clarify the independent relationships that heart rate variability and heart rate recovery displayed with maximal aerobic fitnes...

Symptom-limited maximal oxygen intake (VO SL) and electrocardiographic responses to multistage treadmill test were determined before and after 3 months of physical training in 14 patients with coronary heart disease. Six patients also had hemodynamic studies done at several submaximal work loads in the upright position before and after training. S-T-segment responses were measured by computer a...

OBJECTIVE Our purpose was to assess the diagnostic characteristics of the exercise test in patients who fail to reach conventional target heart rates and in patients on beta-blockers. BACKGROUND Exercise test results are often considered "inadequate" or "nondiagnostic" in patients taking beta-blockers and in patients who do not achieve 85% of their age-predicted maximal heart rate. METHODS ...

We tested the hypothesis that the work of the heart was not a limiting factor in the attainment of maximal oxygen uptake (VO2 max). We measured cardiac output (Q) and blood pressures (BP) during exercise at two different rates of maximal work to estimate the work of the heart through calculation of the rate-pressure product, as a part of the ongoing discussion regarding factors limiting VO2 max...

OBJECTIVE To evaluate heart rate variability during an inspiratory muscle endurance protocol at three different load levels [30%, 60% and 80% of maximal inspiratory pressure], in patients who had previously undergone coronary artery bypass grafting. METHODS Nineteen late postoperative myocardial revascularization patients participating in a cardiovascular rehabilitation program were studied. ...