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Decrease in QRS amplitude in juvenile female competitive athletes during the initial twenty-one months of intensive
Cardiology Journal
|July 25, 2008
Summary
Competitive aerobic gymnastics training in junior female athletes led to a significant decrease in QRS amplitude, specifically the maximum QRS spatial vector magnitude (QRSmax). This finding challenges traditional ECG interpretations of left ventricular hypertrophy (LVH).
Area of Science:
- Sports Cardiology
- Exercise Physiology
- Electrocardiography
Background:
- Competitive training programs can induce physiological adaptations in young athletes.
- Understanding cardiac changes in response to training is crucial for athlete health and performance.
- Aerobic gymnastics places unique demands on the cardiovascular system.
Purpose of the Study:
- To investigate changes in QRS amplitude during 21 months of competitive aerobic gymnastics.
- To analyze the maximum QRS spatial vector magnitude (QRSmax) and Sokolow-Lyon index (SLI) in junior female athletes.
- To assess the impact of early-stage training on cardiac electrical activity.
Main Methods:
- 12 female athletes (13-17 years) underwent regular ECG, heart rate, and blood pressure monitoring over 21 months.
- Somatometric parameters were also recorded at 3-month intervals.
- Analysis focused on QRSmax and SLI, derived from standard 12-lead ECGs.
Main Results:
- A significant gradual decrease in mean QRSmax (-0.8 mV, 30.8%) and SLI (-0.6 mV, 24%) was observed.
- These changes were statistically significant (p < 0.001).
- No significant changes were noted in somatometric parameters, heart rate, or systolic blood pressure.
Conclusions:
- 21 months of aerobic gymnastics training resulted in reduced QRSmax magnitude in junior female athletes.
- This contrasts with the typical ECG criteria for left ventricular hypertrophy (LVH).
- Findings support an alternative hypothesis suggesting a relative voltage deficit in early LVH development.
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