A Modern Definition of the Athlete's Heart-for Research and the Clinic.

Exercise training can have a profound effect on cardiac structure. Recent evidence suggests that the greatest determinants of exercise-induced cardiac remodeling are the intensity, duration, and frequency of training. This also has overlap with athlete fitness. There are many additional factors that are important in determining cardiac remodeling, but while further refinements evolve, the authors argue that the best means of predicting the degree of expected physiologic remodeling is to either quantify training (intensity times total training time) or its by-product (exercise capacity). A uniform approach to estimating the degree of exercise-induced cardiac remodeling will enable more consistent research.