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Updated: Jun 26, 2026

Real-Time Electrocardiogram Monitoring During Treadmill Training in Mice
Published on: May 5, 2022
Electrocardiograms of collegiate football athletes
Stephen F Crouse1, Thomas Meade, Brent E Hansen
1Department of Health Kinesiology, Texas A&M University, College Station, Texas, USA. s-crouse@tamu.edu
Background:
The prevalence of electrocardiogram (ECG) abnormalities in American collegiate football athletes is virtually unknown.
Purpose:
The purpose of this study was to characterize the type and frequency of ECG abnormalities in a sample of football athletes entering National Collegiate Athletic Association (NCAA) Division I Football Bowl Subdivision university program.
Methods:
Over a 4-y period, resting and exercise 12-lead ECG recordings were analyzed by a cardiologist from 68 freshmen and 9 transfer football athletes (n=77; 54 African-Americans and 23 Caucasians, aged 18 +/- 1 y, height=1.89 +/- 0.06 m, weight= 104.4 +/- 19.8 kg) as part of their entry physical examination.
Results:
A total of 79% of the athletes demonstrated at least 1 abnormal ECG finnding, and significantly more African-America athletes (85%) than Caucasian (65%) athletes. Wolff-Parkinson-White (WPW) syndrome was found in 1 African-American player. Frequencies of various ECG abnormal findings in all athletes were: left ventricular hypertrophy = 64.5%, ST-T wave = 6.5%, interventricular conduction delay = 2.6%, sinus bradycardia = 9.1%, sinus arrhythmia = 15.6%, first-degree atrioventricular (AV) block = 11.7%, left atrial enlargement = 48.1%, early repolarization = 33.8%, and right axis deviation = 20.8%. Average values for the PR (0.17 +/- 0.03 s), QRS (0.08 +/- 0.02 s), and QT intervals (0.38 +/- 0.05 s), P-wave duration (0.10 +/- 0.02 s), and QRS axis (79.1 +/- 18.2 degrees) were normal. The ECG responses to maximal treadmill exercise stress tests were evaluated as normal without ischemia or arrhythmias.
Conclusion:
Abnormal resting ECG findings are common in a sample of collegiate football athletes, exceeding the rate expected for their age, and are more frequent in African-American athletes as compared with Caucasian athletes.
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