Objective of the study was to assess the prevalence of significant electrocardiogram anomalies and the prognostic value of the existing risk of sudden death in highly-skilled football players. Methods and structure of the study. We carried out a prospective cohort study to determine the incidence of the electrocardiogram patterns of high risk of sudden cardiac death based on the data obtained in the Russian highly-skilled athletes, members of the men's professional football teams (n=65, mean age-23.3±6.4 years). During the survey, we determined the incidence of significant and insignificant heart rate and cardiac conductivity disorders according to the electrocardiogram data, as well as the dynamics of sports career during the 3-year follow-up period. Study results and conclusions. The electrocardiogram changes (when analyzed on ACCF 2009 recommendations) were found in 80% of the subjects (52 athletes), while 74% of them (59% of the total number, or 38 athletes) were regarded as non-pathological according to all the risk criteria of sudden cardiac death. The total prevalence of abnormal electrocardiogram equaled 21% for ESC and 15% for Stanford criteria and their derivatives-"refined criteria" (TP=0.72, p=0.046). Abnormal electrocardiogram changes were associated with the transition to a sports club of a higher skill level (from a duplicate team to the main or from a lower division team to a higher one) for 3 years of prospective study. The rate of skill improvement in the patients with abnormal electrocardiogram was 60%, in those with normal electrocardiogram-20% (p=0.042). There were no reported sudden deaths during 3 years of prospective study. In highly-skilled football players, the electrocardiogram pattern of high risk of sudden cardiac death can be due to the growth of their sports skills.