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07:26
Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
Abnormal cardiac repolarization in anabolic androgenic steroid users carrying out submaximal exercise testing
Alex S Maior1, Pedro Menezes, Roberto C Pedrosa
1Cardiac Electrophysiology Laboratory, Carlos Chagas Filho Biophysics Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
Clinical and Experimental Pharmacology & Physiology
|October 1, 2010
Summary
Anabolic androgenic steroid (AAS) abuse increases QTc interval and dispersion, indicating ventricular repolarization abnormalities. This may heighten the risk of cardiac arrhythmias and sudden cardiac death in AAS users.
Area of Science:
- Cardiology
- Sports Medicine
- Pharmacology
Background:
- Anabolic androgenic steroid (AAS) abuse is prevalent among athletes.
- Cardiovascular complications are a known risk associated with AAS use.
Purpose of the Study:
- To investigate the cardiovascular effects of AAS abuse.
- To compare electrocardiographic parameters during submaximal exercise between AAS users and non-users.
Main Methods:
- 22 male subjects (11 AAS users, 11 controls) underwent submaximal exercise testing (Astrand-Rhyming protocol).
- Electrocardiographic parameters (QTc, QTd) and heart rate were measured at rest and post-exercise.
Main Results:
- AAS users exhibited significantly higher QTc and QTd intervals at rest and post-exercise compared to controls.
- AAS users showed prolonged QTc intervals post-exercise and reduced heart rate recovery.
- AAS users reported higher exertion at lower workloads.
Conclusions:
- AAS abuse is associated with increased QTc interval and dispersion, suggesting ventricular repolarization abnormalities.
- These abnormalities may increase the risk of cardiac arrhythmias and sudden cardiac death in AAS users.
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