‘Athlete’s heart’ is associated with several structural and electrophysiological adaptations, which are reflected on the 12-lead electrocardiogram (ECG) and imaging studies. Most studies investigating cardiac remodelling in athletes are based on cohorts of white, adult, male athletes competing in the most popular sports. Evidence suggests, however, that sporting discipline and the athlete’s gender and ethnicity are important determinants of cardiovascular adaptation to exercise. Athletes competing in endurance sports demonstrate more pronounced adaptations in comparison to athletes performing static or resistance training. The ECG of endurance athletes is more likely to demonstrate repolarization anomalies in the anterior leads and ventricular dilatation on imaging studies, causing considerable overlap with arrhythmogenic right ventricular cardiomyopathy and dilated cardiomyopathy. Female athletes exhibit less pronounced adaptations compared to males, in terms of the prevalence of ECG changes and absolute cardiac dimensions. Importantly, female endurance athletes are more likely to demonstrate eccentric hypertrophy compared to males, suggesting that concentric remodelling or hypertrophy in female endurance athletes is unlikely to be the consequence of physiological adaptation to training. The most pronounced paradigm of ethnically distinct cardiovascular adaptation to exercise stems from black athletes, who exhibit a significantly higher prevalence of repolarization anomalies and left ventricular hypertrophy compared to white athletes, making the differentiation between athlete’s heart and hypertrophic cardiomyopathy challenging in this ethnic group.