What causes significant fluctuations in heart rate?

There are numerous causes of significant heart rate variability. Common ones include large emotional fluctuations, changes in body position, strenuous physical labor, food digestion, pregnancy, excitement, fear, agitation, alcohol consumption, smoking, and tea drinking. In daily life, it is advisable to engage in regular physical exercise, maintain a positive mood, and ensure adequate sleep. When necessary, traditional Chinese herbal medicine may be used for regulation. Additionally, marked heart rate fluctuations may stem from cardiac conditions such as supraventricular tachycardia or Wolff-Parkinson-White syndrome.