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Left ventricular responses to a program of lower-limb strength training
Chest
|October 1, 1980
Summary
Lower limb strength training in healthy men increased heart function and left ventricular thickness without improving maximal oxygen uptake. This suggests strength training enhances cardiac performance similar to elite athletes.
Area of Science:
- Cardiology
- Exercise Physiology
- Sports Medicine
Background:
- Strength training is known to induce physiological adaptations.
- The effects of lower limb-specific strength training on cardiac structure and function in healthy individuals require further elucidation.
Purpose of the Study:
- To investigate the impact of a 10-week lower limb strength training program on cardiac function and structure in healthy young men.
- To assess changes in maximal oxygen uptake and left ventricular parameters following the training intervention.
Main Methods:
- Nine healthy males (18-27 years) underwent a 10-week strength training program involving squats, leg extensions, leg flexions, leg presses, and calf raises.
- Echocardiograms and physiological evaluations were performed before and after the training period.
- Maximal oxygen uptake, heart rate, left ventricular wall thickness, left ventricular mass, and fractional shortening were measured.
Main Results:
- Resting heart rate decreased significantly (P < .001).
- Left ventricular wall thickness (P < .05), left ventricular mass (P < .05), and left ventricular fractional shortening (P < .001) increased significantly.
- Maximal oxygen uptake did not show a significant change.
- Improvements in left ventricular performance were observed without significant changes in ventricular volumes.
Conclusions:
- Lower limb strength training in healthy individuals can lead to cardiac adaptations, including increased left ventricular wall thickness and improved performance.
- These cardiac adaptations are comparable to those observed in elite strength-trained athletes.
- Strength training does not necessarily increase maximal oxygen uptake but enhances cardiac efficiency.
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