Is bradycardia (heart rate in the 50s) common in asymptomatic athletes, such as wrestlers?

Bradycardia in Athletes: Normal Physiological Adaptation

Bradycardia with a heart rate in the 50s is completely normal in asymptomatic athletes, including wrestlers, and represents a physiological adaptation to regular training that does not require further evaluation. 1

Physiological Basis of Athletic Bradycardia

Athletic bradycardia is a well-documented cardiovascular adaptation to regular intensive exercise and is particularly common in endurance sports but occurs across many athletic disciplines. This adaptation results from:

• Increased parasympathetic (vagal) tone
• Decreased resting sympathetic tone
• Intrinsic adaptations of the sinoatrial node independent of neural input 1

According to international recommendations from the Journal of the American College of Cardiology, heart rates as low as 30 beats per minute can be considered normal in highly trained athletes when asymptomatic 1.

Clinical Significance and Assessment

In an asymptomatic athlete with a heart rate in the 50s:

• No further evaluation is required if:
  • The athlete is asymptomatic (no dizziness, syncope, or exercise intolerance)
  • There is no family history of inherited cardiac disease or sudden cardiac death
  • Heart rate normalizes appropriately during exercise 1

The European Heart Journal guidelines specifically state that bradycardia "is the result of a physiological adaptive change of the autonomic nervous system and reflects the level of athletic conditioning" 1.

When to Consider Further Evaluation

Further assessment would only be warranted if:

1. Heart rate drops below 30 beats per minute during waking hours
2. Symptoms such as dizziness, syncope, or exercise intolerance are present
3. There is a family history of sudden cardiac death or inherited cardiovascular disease
4. The athlete has abnormal physical findings
5. The bradycardia does not resolve appropriately with exercise 1

Other Common ECG Findings in Athletes

Athletes commonly display other ECG findings that might be considered abnormal in non-athletes but are normal physiological adaptations in trained individuals:

• Sinus arrhythmia (heart rate variation with respiration)
• First-degree AV block (PR interval 200-400 ms)
• Mobitz Type I (Wenckebach) second-degree AV block
• Increased QRS voltage meeting criteria for ventricular hypertrophy
• Early repolarization patterns 1, 2

Conclusion

For an asymptomatic wrestler with a heart rate in the 50s, this finding represents a normal cardiovascular adaptation to athletic training. The bradycardia should resolve during exercise, confirming its physiological nature. No further cardiac evaluation is necessary in the absence of symptoms, abnormal physical findings, or concerning family history.