Differences in cardiac function with prolonged physical training for cardiac rehabilitation.
Ten men aged 40 to 68 years with clinical manifestations of cardiovascular disease and who had participated for 2 to 59 months in a physical training program for cardiac rehabilitation were studied. All 10 underwent measurements of maximal oxygen uptake and invasive studies of cardiac output, using the direct Fick method, at rest and at graded levels of exercise in the upright posture. Of four men who left the training program, three continued activities individually. Physiologic measurements were repeated after a lapse of 13 to 38 months (average 23 months). The rate of change in maximal oxygen uptake relative to normal changes with aging was decelerated in four men over an average of 21.8 months and was accelerated in six men over an average of 23.2 months. At comparable oxygen requirements of exercise, stroke volume and cardiac output were unchanged in the former group but significantly decreased in the latter. Arterial oxygen content and arteriovenous oxygen difference increased in both groups. These results show that prolonged physical training results in physiologic adaptations of cardiac rehabilitation even though deterioration of cardiac function with advancing disease is probable in some patients.
D000328:Adult; D000368:Aged; D002302:Cardiac Output; D002318:Cardiovascular Diseases / Q000503:physiopathology / Q000628:therapy*; D006321:Heart / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D010101:Oxygen Consumption; D010806:Physical Education and Training; D005082:Physical Exertion; D013997:Time Factors
D010100:Oxygen