Influence of training on myocardial responses of rats subjected to conditions of ischaemia and hypoxia.

Physical training has been advocated to minimize the problems associated with coronary heart disease; however, the responsible mechanisms are obscure. Rats trained to run on a treadmill were subjected to acute conditions of hypoxia and myocardial ischaemia. Trained rats were better able to maintain a higher level of cardiac performance (dP/dt max) after hypoxia than non-trained rats, but no advantages were apparent after ischaemia. Biochemical data showed no myocardial differences between the groups in oxygen utilization or energy availability.