I have searched for a good source on sudden death in athletes for some time now. Finally, I found an excellent one put up by the Minneapolis Heart Institute Foundation Sudden Death in Athletes.
The most common cause is Hypertrophic Cardiomyopathy (HCM). That large, slow-beating “athletic” heart may kill you. So can alcohol, energy drinks, and steroids. Which activity is most dangerous? You may see why I play tennis now. Weight lifting didn’t make the grade, but competitive lifting is such a small sport. In part, the sports with the most participation rank highest. The incidence per athlete in the sport is not really known.
According to the Institute:
“Systemic training in endurance (dynamic, aerobic) or isometric sports (static, power) has been known to increase cardiac mass and dimensions, and trigger structural remodeling in many athletes (18-22). This form of hypertrophy is physiologic and is regarded as an adaptation to systematic athletic training, and therefore was termed “athleteâs heart.” The changes include enlargement of left and right ventricles and left atrium; however the function of the heart remains preserved. Physiologic increases in cardiac mass vary in magnitude according to sporting discipline. For example, the most extreme cavity dimensions and/or wall thickness have been reported with rowing, cross-country skiing, cycling and swimming. Weight lifting and wrestling have been associated with abnormal increases in left ventricular wall thickness disproportionate to cavity size.”
I noted the disruption of contraction pulses, ischemia or blood loss and consequent damage to heart muscle in an earlier post. That damage is then infiltrated by scar tissue and, as a result, the contraction waves become disorganized and arrhythmia may follow.