this report describes the results of a study designed to evaluate in rhesus monkeys the potential for adriamycin to induce cardiomyopathies following treatment and to evaluate the influence of exercise on development of this syndrome. development of myocardial dysfunction was detected by evaluation of parameters obtained from echocardiograms, including shortening fraction, velocity of circumferential fiber shortening, and systolic time interval indices additionally, electrocardiography, certain serum enzymes, hematology, and morphologic studies were used to evaluate induced changes following extensive baseline measurement animals were treated with adriamycin until indices of contractility indicated cardiac compromise. then one half of the animal population was trained to exercise vigorously using automated exercise devices. animals were exercised for approximately eleven months. numerous echocardiographic analyses were performed during this period. following necropsy extensive statistical analyses of pathology and echocardiography data were made. the conclusions of the study were: exercise did not enhance cardiotoxicity in rhesus monkeys which had been previously treated with adriamycin. the exercise regimen was adequate to condition animals. echocardiographic parameters are useful in monitoring for and predicting adriamycin induced cardiotoxicity in rhesus monkeys but they are not good indicators of histologic changes. most of the monkeys were administered an amount of adriamycin which induced a decrease in myocardial function as demonstrated by echocardiography and myocar