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What heart rate is unhealthy?

A healthy resting heart rate can give an indication of cardiovascular fitness and provide insight into overall health. But what heart rate levels should raise concern? Here is an overview of unhealthy heart rate ranges for adults and when to see a doctor.

What is considered a normal heart rate?

A normal resting heart rate for adults ranges from 60 to 100 beats per minute (bpm). Well-conditioned athletes may have a resting heart rate closer to 40 bpm. Here are some general guidelines for average resting heart rate by age:

  • Newborns: 70 to 190 bpm
  • Infants: 100 to 150 bpm
  • Toddlers: 80 to 130 bpm
  • Preschoolers: 70 to 115 bpm
  • Children ages 6 to 15: 60 to 105 bpm
  • Adolescents: 50 to 90 bpm
  • Adults: 60 to 100 bpm

It’s normal for heart rate to rise with exercise and activity and fall when resting. The best time to get an accurate resting heart rate measurement is in the morning after waking up.

What is bradycardia?

Bradycardia refers to a resting heart rate that is lower than 60 bpm. While trained athletes may have heart rates in the 40s, the following groups may have underlying causes of bradycardia:

  • Adults: Resting heart rate below 50 bpm
  • Children ages 6 to 15: Below 60 bpm
  • Infants and children under 6: Below 70 bpm

Possible causes of bradycardia in non-athletes include:

  • Hypothyroidism
  • Electrolyte imbalances
  • Sleep apnea
  • Heart block
  • Medications like beta blockers
  • Heart disease
  • Sick sinus syndrome

Symptoms of bradycardia may include:

  • Fatigue
  • Dizziness
  • Fainting or near fainting
  • Shortness of breath
  • Chest pain
  • Confusion

Seek medical care if you experience symptoms of bradycardia along with an abnormally slow heart rate. Sudden bradycardia can be life-threatening.

What is tachycardia?

Tachycardia refers to a resting heart rate above 100 bpm in adults. Some heart rate ranges indicating tachycardia include:

  • Adults: Consistently above 100 bpm
  • Children ages 6 to 15: Above 105 bpm
  • Infants and children under 6: Above 150 bpm

Possible causes of tachycardia include:

  • Hyperthyroidism
  • Anemia
  • Heart disease
  • Arrhythmias
  • Stimulants
  • Fever
  • Anxiety

Symptoms of tachycardia may include:

  • Heart palpitations
  • Shortness of breath
  • Chest pain
  • Lightheadedness
  • Rapid pulse
  • Heart fluttering

Seek prompt medical care if these symptoms accompany an abnormally rapid heart rate. Sustained tachycardia can significantly impact heart function.

Is exercise heart rate unhealthy?

During exercise, heart rate normally rises in order to circulate more oxygenated blood to the muscles. Heart rate ranges during exercise depend on fitness level, exertion level, age, and current state of health.

As a general guideline, maximum heart rate during exercise is calculated as 220 minus your age. So for a 30 year old, the estimated maximum heart rate would be 190 bpm (220 – 30 = 190 bpm). However, this is just an estimate and maximum heart rate can vary quite a bit between individuals.

Target heart rate zones during exercise are often defined as 50-85% of your maximum heart rate. However, these target zones also depend on your fitness goals.

Here are some typical target heart rate zones during exercise:

  • Moderate exercise: 70-77% of maximum
  • Vigorous exercise: 77-93% of maximum

As long as heart rate recovers back to normal within a few minutes after stopping exercise, elevated heart rate during activity is considered healthy and a sign of cardiovascular fitness. However, sustained tachycardia after exercise may be cause for concern.

Abnormal heart rhythms

A consistently irregular heartbeat that is too fast, too slow, or erratic may signal an underlying heart rhythm disorder (arrhythmia). Some examples of arrhythmias include:

  • Atrial fibrillation – irregular and rapid heart rate
  • Supraventricular tachycardia – rapid heart rate originating above the ventricles
  • Ventricular tachycardia – rapid heart rate originating from the ventricles
  • Bradyarrhythmias – slow heart rate disorders like heart block

Abnormal heart rhythms can negatively impact heart function. Symptoms may include palpitations, dizziness, shortness of breath, fainting, and chest pain. Seek medical care if you experience recurring episodes of abnormal heart rhythms.

Warning signs of dangerously high heart rate

While exercise and stress can accelerate your heart rate temporarily without danger, a heart rate that remains very rapid at rest could signal a medical emergency like:

  • Very rapid heart rate over 150 bpm in adults, known as sinus tachycardia
  • Supraventricular tachycardia
  • Ventricular tachycardia
  • Wolff-Parkinson White syndrome

Abnormally high heart rate is considered an emergency when accompanied by:

  • Chest pain
  • Shortness of breath
  • Lightheadedness
  • Fainting
  • Palpitations
  • Low blood pressure

Extremely rapid heart rate can significantly reduce blood flow to vital organs. Call 911 if you experience these symptoms along with an exceedingly fast pulse over 150 bpm.

Health risks of chronic tachycardia

While temporary tachycardia is common during exercise and stress, chronic tachycardia (persistently elevated resting heart rate over 100 bpm) can have adverse long-term effects on your health. Some impacts of long-term tachycardia include:

  • Increased risk of heart failure
  • Higher chance of stroke
  • Increased risk of atrial fibrillation
  • Higher mortality risk

The risks are even greater if the underlying cause involves impaired heart function. Monitoring heart rate trends over time and discussing any abnormalities with your doctor is important for identifying potential health issues.

When to see a doctor

Consult a doctor promptly if you experience any of the following:

  • Resting heart rate consistently outside the normal range for your age (too slow or too fast)
  • Palpitations or irregular heart beats
  • Episodes of rapid heart rate accompanied by dizziness, shortness of breath, or chest pain
  • Persistent lightheadedness or fainting

A medical evaluation can help identify or rule out any underlying heart conditions. Your doctor may order an ECG test to check electrical signals in the heart and monitor holter to track heart rate trends. Prompt treatment is important, especially for high risk heart rate abnormalities.


A heart rate outside the normal range may simply reflect being out of shape or high fitness. But chronically too fast, too slow, or erratic heart rate can signal underlying medical conditions. Seeking timely medical care for symptoms like dizziness and chest pain along with abnormal heart rate is critical, as certain heart rhythm disorders can worsen rapidly if left untreated. Monitoring your heart rate trends, maintaining cardiovascular fitness, and discussing any concerns with your doctor can help keep your heart rate and heart health on track.