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Influence of type and duration of training on the presence of an abnormal ECG in high-performance athletes
Geoffrey Verrall1, Angus Hains2, Bronte Ayres2
1Department of Sports Medicine, South Australian Sports Institute, Brooklyn Park, South Australia, Australia.
Objective:
To undertake an ECG in high level athletes to determine the morphology of the ECG and to assess the influences on the ECG of the amount of time in a high-performance programme and the type of sport played.
Design:
Cross-sectional cohort study.
Setting:
High-performance sports programme.
Interventions:
Current symptoms (questionnaire) and length of time in a high-performance sports programme were recorded. Sports were classified as either high maximal oxygen uptake continuous, high maximal oxygen uptake repeated effort or static. An ECG was performed and classified by 2010 European Society of Cardiology guidelines into Groups 0 (normal), Group 1 (common and training-related ECG changes) and Group 2 (uncommon and training unrelated ECG changes).
Results:
The following were recorded: length of time in high performance sport programme (mean 2.3 years), type of sport (Continuous 103, Repeated effort 133, Static 37), ECG changes Group 0 (n=83, 31%), Group 1 (n=173, 63%) and Group 2 (n=17, 6.2%). Athletes with an increased length of time in a high performance programme demonstrated a higher likelihood of Group 2 ECG changes when compared with Groups 0 and 1 (p=0.05). The questionnaire did not help detect athletes with Group 2 ECG changes.
Conclusions:
This study demonstrates that an increased length of time in a high performance programme was associated with an increased number of detectable Group 2 ECG changes. Overall, the further investigation rate was 6.2%.
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