Related Experiment Videos
Left ventricular performance during prolonged exercise: absence of systolic dysfunction
J M Goodman1, P R McLaughlin, P P Liu
1Faculty of Physical Education and Health, University of Toronto, 55 Harbord Street, Toronto, Ontario, Canada M5S 2W6. jack.goodman@utoronto.ca
Clinical Science (London, England : 1979)
|April 11, 2001
Summary
Prolonged exercise did not impair left ventricular function in healthy men, suggesting moderate-duration exercise does not cause cardiac fatigue. This study assessed cardiac performance during and after sustained physical exertion.
Area of Science:
- Cardiology
- Exercise Physiology
- Sports Medicine
Background:
- Previous research on prolonged exercise and left ventricular function is inconclusive regarding cardiac fatigue.
- Understanding the impact of sustained exertion on cardiac performance is crucial for athletes and clinicians.
Purpose of the Study:
- To evaluate left ventricular systolic and diastolic function during and after prolonged exercise in trained men.
- To determine if prolonged exercise can induce left ventricular dysfunction or cardiac fatigue.
Main Methods:
- 15 healthy trained men exercised on bicycles at 60% maximum oxygen uptake for 150 minutes.
- Left ventricular function was assessed using radionuclide angiography at rest, during exercise, and post-exercise.
- Gas exchange, blood pressure, and hematocrit were monitored concurrently.
Main Results:
- No significant changes in left ventricular ejection fraction or end-systolic volume were observed.
- A small decline in end-diastolic volume occurred at 150 minutes of exercise.
- Heart rate increased during exercise, and remained elevated post-exercise, but systolic and diastolic blood pressure were unchanged.
Conclusions:
- Prolonged, moderate-intensity exercise does not appear to induce abnormal left ventricular systolic function or cardiac fatigue in healthy, trained men.
- The heart maintains normal systolic function despite sustained physical exertion and increased heart rate.
- Further research may explore the effects of higher intensities or longer durations on cardiac function.