The goals of this study were to determine the prevalence and determinants of false-positive exercise tests in athletes. Data from all athletes who visited the Department of Sport Medicine for assessment of sports eligibility during a 1.5-year period were reviewed retrospectively. Potential determinants of (false) positive test results that were evaluated included demographics, cardiovascular risk factors, sports characteristics, resting electrocardiogram (ECG) abnormalities, and exercise capacity. Data from 1298 athletes were included. In 53 athletes (4.1%), the exercise ECG was classified as positive. Among 38 athletes who were referred to a sports cardiologist for further diagnostic evaluation, 36 (95%) were classified as having a false-positive test result and 2 athletes (5%) required coronary revascularization. Athletes with a false-positive test were older than athletes with a negative test (53 ± 8 vs 45 ± 13 years,P= 0.03). In conclusion, exercise electrocardiography has a low positive predictive value in asymptomatic recreational and competitive athletes, with a false-positive test result being associated with higher age. Given the relatively high prevalence of false-positive test results in this population, efforts should be made to develop strategies aimed at identifying false-positive test results in a simple noninvasive manner.