CHEUNG, J. Y., J. SONG, L. I. ROTHBLUM, and X.-Q. ZHANG. Exercise training improves cardiac function after infarction: special emphasis on recent controversies on Na+/Ca2+exchanger. Exerc. Sport Sci. Rev., Vol. 32, No. 3, pp. 83–89, 2004. Exercise training instituted after myocardial infarction improves many steps involved in cardiac excitation–contraction coupling. Focusing on Na+/Ca2+exchange, current controversies regarding whether it mediates Ca2+influx during an action potential, whether it is increased or decreased in disease models, whether protein kinase A alters its activity, and whether exercise training affects its function are reviewed. Finally, a novel target for exercise training in the heart is suggested.