Your sleeping heart rate may be lower than your resting heart rate, according to the Cleveland Clinic. It may drop below 60 beats per minute. For most people, that is not a problem. However, bradycardia is a heart rate below 60 while you're awake and active, and that could be a problem.
"Your heart rate slows down during sleep. A normal resting heart rate for adults is anywhere between 60 to 100 beats per minute. During sleep, the normal rate can be anywhere from 40 to 100," says Peter Santucci, MD, professor of cardiology at Loyola University Medical Center in Maywood, Illinois.
Read more: What Is Your RHR and Why Should You Care?
Bradycardia: How Low Is Too Low?
While a normal sleeping heart rate can dip below 60, the Cleveland Clinic explains that a sustained heart rate below 60 when you're not sleeping or resting may be a medical condition called bradycardia.
Bradycardia is a condition that increases with age. It's most common in men and women over age 65, Cleveland Clinic says. Although healthy and fit young people and trained athletes can have heart rates down into the 40s without any symptoms, bradycardia may cause symptoms for other people. These can include:
- Chest pain.
- Shortness of breath.
- Heart palpitations.
The most common cause of symptomatic bradycardia is a problem that develops with the heart's natural pacemaker, called the sinus node, Cleveland Clinic notes. There may also be a block of electrical signals between the upper and lower chambers of the heart, called an AV block. Another common cause is a heart or blood pressure medication that slows down the heart, it says.
"Symptoms of bradycardia may only be felt during activity. You could have a heart rate of 50 at rest without any symptoms, but if you get up and active, even a heart rate of 60 or 65 could be too slow and cause symptoms. If you have symptomatic bradycardia, you may need treatment," Dr. Santucci says.
Mayo Clinic recommends letting your doctor know if you're not a trained athlete and your resting heart rate is under 60. This is even more important if you have symptoms of bradycardia.
The Cleveland Clinic also warns that a heart rate that drops into the 30s might mean that you're not getting enough oxygen to your brain. This may cause other symptoms such as fainting, lightheadedness or shortness of breath, or allow blood to back up in the heart. Checking in with your doctor for evaluation is key, as there are treatments that can help.
Tachycardia: How High Is Too High?
"A resting heart rate that is frequently over 110 or occasionally over 140 can lead to heart damage or heart failure and may need to be treated," Dr. Santucci says. According to the American Heart Association, the medical term for a heart rate above 100 is tachycardia. Symptoms may include:
- Passing out.
- Pounding pulse.
- Chest pain or pressure.
- Shortness of breath.
Although the range of normal for a resting and sleeping heart rate is wide, the Mayo Clinic says to let your doctor know if your resting heart rate is consistently above 100, especially if you have any symptoms of tachycardia.
Benefits of Sleep for Heart Health
According to the Centers for Disease Control and Prevention (CDC), getting enough sleep is very important for heart health. During sleep, both your heart rate and your blood pressure go down. Most adults need at least seven hours of sleep to allow the body to rest and repair.
The CDC says that lack of sleep may raise your risk for heart disease, heart attack and stroke. Lack of sleep is also linked to health problems, such as type 2 diabetes and obesity, which can contribute to heart disease.
Read more: 5 Simple Steps to Get the Best Night of Sleep Ever
Is This an Emergency?
- Cleveland Clinic: “Is a Slow Heart Rate Good or Bad for You?”
- Peter Santucci, MD, professor of cardiology, Loyola University Medical Center, Maywood, Illinois
- Mayo Clinic: “What’s a Normal Resting Heart Rate?”
- American Heart Association: “Tachycardia: Fast Heart Rate”
- Centers for Disease Control and Prevention: “How Does Sleep Affect Your Heart Health?”