Exercise can protect against a broken heart.

Introduction Coronary artery disease remains a dominant cause of death around the world. The major pathology associated with coronary artery disease is ischemia reperfusion (IR)-induced cardiac injury (i.e., heart attack). Given the high incidence of heart attacks, developing a practical countermeasure to protect against IR-induced cardiac damage is important. Fortunately, a simple intervention exists V regular exercise. Indeed it is well established that regular endurance exercise training (e.g., running, cycling, swimming, etc.) can protect against IRinduced cardiac injury; this commonly is called exerciseinduced ‘‘cardioprotection.’’ This report summarizes our current understanding of how and why regular exercise provides protection against IR-induced myocardial injury. We begin with a brief summary of the evidence demonstrating that exercise is cardioprotective; this will be followed by a discussion of the mechanisms responsible for this protection. The remainder of this report focuses on how primary care physicians can translate this basic research into recommendations to encourage their patients to engage in a regular exercise program that results in cardioprotection.