Regular exercise is highly effective in cardiovascular health improvement. Professional athletes have always been regarded as exemplars of good health and have also attracted scientific curiosity on account of the strength and endurance that characterize their lifestyle. Over a period of time in athletes, cardiac adaptations to sport activities occur. The normal electrocardiographic (ECG) presentation of the heart is changed and abnormal pattern becomes present. Some of these abnormal ECG changes are suggested to be maladaptations that are risk factors for sudden cardiac death. Does the abnormal ECG pattern have anything to do with the training age of the athletes? The aim of this study is to determine the relationship between electrocardiographic abnormalities and training age of athletes in Port Harcourt, Nigeria. A cross sectional descriptive study was carried out on a total of 170 athletes consisting of 63males and 107 females (16-35years of age). Their training ages were documented and the athletes were grouped into 3: Group 1 are athletes that have been training for 1-5years; group 2 : 6-10years and group 3 from 10 years and above. Anthropometric measurements and heart rates were determined. Physical examination was conducted to exclude the presence of associated co-morbidities. Electrocardiographic parameters were determined using a standard resting 12-lead electrocardiogram. Maladaptive ECG changes were determined using the Seattle criteria. Results showed that the training ages of athletes negatively correlated significantly with heart rate(R=-0.24; P=0.001) and T-axis (R=-0.24; P=0.01). Also training age positively correlated significantly with QRS- Interval (R=0.16; 0.03) and QT- Interval (R= 0.22; 0.001). Athletes in group 3 (training age > 10years) recorded a significantly higher percentage of the occurrence of repolarization abnormality (ꭕ2 =5.50; p= 0.04). In addition, being a female and increased training age, are the significant predictors of the occurrence of a maladaptation. (Odd ratio=4.38; p=0.003 and odd ratio = 1.14; p=0.03 respectively). The abnormal electrocardiographic changes found in this study may be due to some physiological maladaptation resulting from prolonged training age and possibly sex variation. These maladaptations are suggestive of risk factors for possible sudden cardiac death.