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Updated: Aug 5, 2026

Rodent Working Heart Model for the Study of Myocardial Performance and Oxygen Consumption
Published on: August 16, 2016
Left Ventricular Mechanics and Myocardial Work in Competitive Sprinters
1Department of Cardiology, Dr. Siyami Ersek Cardiovascular and Thoracic Surgery Center, Istanbul, Turkey.
Background:
Sprint exercise is characterized by repeated short-duration high-intensity anaerobic activity associated with distinct hemodynamic and autonomic adaptations. However, the effects of long-term sprint training on left ventricular (LV) mechanics and myocardial work (MW) parameters remain insufficiently investigated. This study aimed to evaluate LV global longitudinal strain (GLS) and MW indices in competitive sprinters.
Methods:
A total of 65 competitive sprinters and 40 age- and sex-matched healthy sedentary controls were prospectively enrolled. All participants underwent comprehensive transthoracic echocardiography, including two-dimensional speckle-tracking echocardiography and non-invasive myocardial work analysis. GLS, global myocardial work index (GWI), global constructive work (GCW), global wasted work (GWW), and global myocardial work efficiency (GWE) were quantified.
Results:
Resting heart rate was significantly lower, whereas stroke volume was significantly higher in sprinters compared with controls. However, LV GLS and principal MW indices, including GWI, GCW, GWW, and GWE, were comparable between groups (all p > 0.05). Intra- and interobserver reproducibility for MW measurements demonstrated good-to-excellent agreement.
Conclusion:
Long-term sprint training appears to be associated with preserved myocardial mechanics and myocardial work indices despite chronic exposure to high-intensity anaerobic exercise, supporting the presence of physiological rather than maladaptive cardiac adaptation in competitive sprinters.
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