Electrocardiographic patterns and long-term training-induced time changes in 2484 elite football players.

Background: High-level physical training induces cardiac structural and functional changes, including 12-lead electrocardiogram modifications.

Objectives: The purpose of this cross-sectional longitudinal study was to establish a quantitative electrocardiographic profile in highly trained football players. Initial and serial annual electrocardiogram monitoring over subsequent years allowed us to investigate the long-term effects of exercise on cardiac conduction and electrophysiological remodelling.