Left ventricular mechanics and arterial-ventricular coupling following high-intensity interval exercise
Anita T Cote1, Shannon S D Bredin, Aaron A Phillips
1Cardiovascular Physiology and Rehabilitation Laboratory, University of British Columbia, Vancouver, Canada;
Journal of Applied Physiology (Bethesda, Md. : 1985)
|September 21, 2013
Summary
High-intensity exercise impairs cardiac function, particularly in men, by affecting ventricular mechanics and arterial elastance. These changes are linked to arterial stiffness, not catecholamine levels.
Area of Science:
- Cardiovascular Physiology
- Exercise Physiology
- Cardiac Mechanics
Background:
- High-intensity exercise causes physiological stress, potentially impacting catecholamine secretion and cardiac beta receptors.
- Impaired cardiac function post-exercise may involve attenuated arterial-ventricular coupling and vascular mechanisms.
Purpose of the Study:
- To evaluate left ventricular function and mechanics before and after high-intensity interval exercise.
- To investigate the influence of sex and training status on post-exercise cardiac function.
- To explore the relationship between cardiac function, catecholamine levels, and vascular properties.
Main Methods:
- Echocardiographic assessment of left ventricular function in normally active and endurance-trained men and women.
- High-intensity interval exercise protocol involving cycling at 100% peak power output.
- Measurement of catecholamine levels, arterial elastance, and aortic pulse-wave velocity.
Main Results:
- Exercise delayed time to peak twist and peak untwisting velocity (P < 0.01).
- Sex-specific differences observed in longitudinal diastolic strain rate and arterial elastance post-exercise.
- No association found between cardiac variables and catecholamine levels.
- Changes in twist mechanics correlated with baseline aortic pulse-wave velocity (r(2) = 0.27, P = 0.001).
Conclusions:
- Males exhibit greater reductions in contractility following high-intensity interval exercise, independent of catecholamines.
- Post-exercise cardiac mechanics are influenced by arterial stiffness, highlighting the role of vascular integrity.
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