Background The 12-lead ECG is not only necessary for diagnosing the sports aptitude of players, but it also provides information on their training condition and cardiovascular adaptations to exercise.

Objective To determine the electrocardiographic adaptations of high-level volleyball players and relate them to their level of training.

Design Retrospective study over the course of 18 years, from 1992 to 2009. We analyzed the ECGs taken at the start of each season as part of routine medical test. We analyzed 1080 ECGs (15 players/18 years/4 teams – two male and two female).

Setting and participants Male and female youth and Honor Division teams from the same club. 180 women (94 youth, 86 senior) and 210 men (126 youth, 84 senior) (mean age, height, weight).

Intervention In August–September of each season, a resting ECG was taken for each player to determine pre-competitive fitness. Independent variables: sex, age, years of training. Dependent variables: P waves, QRS, T in duration and voltage and ECG evaluation (axes).

Results ECG/player Average: 5.6±1.9, FC resting: 66.3±3 bpm. Left ventricular hypertrophy: 38.95%±8.9; Right ventricular hypertrophy: 12.77%±3.4. Right Bundle Branch Block: 25.64%±8.3. Participants who required echocardiography: eight players: ST segment depression. five players: Inverted or flattened T wave in two or more leads. Three men and two women: Corrected QT interval prolongation in heart rate (QTc)> 0.44 s in men and> 0.46 s in women. Echocardiography ruled out organic disease. There were no differences in terms of years of training or level.

Conclusions Electrocardiographic adaptations in volleyball are similar to those in the literature for team sports. There was no pathological study and all were declared fit for the high-level sport.