There are several things that can fluctuate throughout the day—your energy level, your weight—and your heart rate is another. There are many factors that can make it vary as you go about your routine. Stress and exercise can make it higher while sleep can lower it.
“As your body’s demand for energy fluctuates throughout the day, your heart rate will adjust accordingly to meet those energy requirements,” says Estelle D. Jean, MD, a board-certified cardiologist. “Your heart rate will increase in response to physical activity, to stimulants such as caffeine, or during periods of emotional stress, anxiety, and pain. It can also decrease while you are sitting, sleeping, or meditating.”
In case you didn’t know, a normal sleeping heart rate is between 40 and 50 beats per minute (BPM), although this can vary from person to person. Ahead, you’ll discover everything you need to know about your heart rate while sleeping, what’s considered too low, and how to manage your heart rate during sleep.
Average heart rates
Resting heart rate
“Resting heart rate is a measure of your heart rate while at rest and relaxed,” says Jean. She adds that the normal average heart rate ranges from 60 to 100 BPM.
But this is something that can be different from person to person for several reasons. For example, some people may have a resting heart rate as low as 30 BPM, and it can also decrease by age, as proven through study.
“For many individuals, a heart rate less than 60 BPM may be an indicator of cardiovascular fitness, as well-conditioned athletes typically have a slower resting heart rate,” Jean explains. “It is important to consider factors such as age, physical fitness, medications, underlying medical conditions, and symptoms when trying to determine if the slow heart rate is problematic.”
Heart rate during exercise
It’s only natural that your heart rate increases during exercise—that means you’re doing it right. In fact, the Centers for Disease Control and Prevention (CDC) has targeted heart rates you can aim for during exercise, ranging anywhere from 109 BPM to 172 BPM.
“Your heart rate will increase during exercise to supply more oxygen to your muscles,” Jean says.
Just be sure to consult with a doctor before starting a vigorous exercise program and go over any risk factors you may have.
Heart rate while sleeping
During sleep, your average sleeping heart rate will go down to 40 to 50 BPM, but again, this can vary. It’s not uncommon to have a heart rate in the 30s while sleeping—and Jean says it can briefly drop as low as 30 BPM while sleeping in a healthy individual.
Noting that your sleeping heart rate will typically be lower than your daytime resting heart rate, Jean says a normal sleeping heart rate depends on several factors, such as age and physical fitness.
How does your heart rate change while you sleep?
Your heart rate isn’t only affected by the act of sleeping but by where you’re at in your sleep cycle as well.
Jean says a normal response to sleep is a decrease in heart rate. The heart rate is slowest during deep sleep and may increase during rapid eye movement (REM) sleep, which is when the majority of your dreams take place.
What can affect your sleeping heart rate?
Several factors can affect your sleeping heart rate, making it go higher or lower. According to Jean, these causes can include:
- Physical fitness
- Getting sick
- Sleep apnea
- Underlying medical conditions
She adds that with all these factors to consider, it’s not surprising resting heart rate can vary from person to person.
What is a dangerously low sleeping heart rate?
While your sleeping heart rate can undoubtedly fluctuate, there’s such a thing as a dangerously low heart rate while sleeping. This is something that shouldn’t be overlooked and necessitates a conversation with your doctor.
“Obstructive sleep apnea is an important health condition that can cause significantly slow heart rates (less than 30 BPM) during episodes of low oxygen levels while sleeping,” explains Jean. “Sudden drops in blood oxygen levels that occur during sleep apnea can put a strain on the heart and cardiovascular system.”
Jean adds that severe obstructive sleep apnea has been associated with high blood pressure, coronary artery disease, heart failure, stroke, other arrhythmias such as atrial fibrillation and ventricular arrhythmias, and sudden cardiac death.
How can you measure your sleeping heart rate?
If you’re sleeping, how can you figure out what your sleeping heart rate is? With a smartwatch and/or app that can help track it.
Jean says there are several such devices on the market. “Common devices frequently used by my patients include the Apple Watch and KardiaMobile,” she says. “If your provider suspects that you may have a sleep disorder, they may also recommend a sleep study.”
It can also be beneficial to measure your heart rate while not sleeping.
“It’s best to measure your heart rate when you are relaxed and at rest,” says Jean. “Avoid measuring your heart rate after exercising, drinking coffee, smoking a cigarette, or when feeling stressed and anxious.”
How can you manage your sleeping heart rate?
While it may seem largely out of your control, there are actually several ways you can ensure your sleeping heart rate is in the normal range. With a focus on engaging in healthy lifestyle habits that improve overall cardiovascular health, these ideas from Jean include:
- Exercise regularly, aiming for at least 150 minutes a week of moderate-intensity fitness and two days a week of strength training. “Being physically fit is associated with a lower resting heart rate,” Jean says.
- Eat a healthy diet. Some examples include the Mediterranean diet, a plant-based diet, a flexitarian diet, and the DASH diet (which is a dietary approach to stopping hypertension). “You want to avoid processed foods and limit your intake of unhealthy fats,” says Jean. “A heart-healthy diet consists of fruits, vegetables, whole grains, legumes, and lean sources of protein, such as fish and poultry over red meat.”
- Avoid nicotine.
- Avoid caffeine before going to bed.
- Limit alcohol intake to the recommended amount (one serving a day for women and two servings a day for men). “Alcohol in excess has been linked to poor sleep quality and insomnia,” Jean says. “You should avoid drinking alcohol before going to bed.”
- Get the recommended seven to nine hours of sleep at night.
- Reduce stress and anxiety. Consider yoga, meditation, therapy, and deep breathing exercises.
- Get treatment for underlying conditions such as hypothyroidism and sleep apnea.
“Normal sleeping heart rate depends on several factors, which is why it’s important to consult with your medical provider if you have any concerns or symptoms,” Jean concludes.
What is a good heart rate when sleeping?
During sleep, your average sleeping heart rate will go down to 40 to 50 BPM, but this can vary. It’s not uncommon to have a heart rate in the 30s while sleeping.
What is an unsafe heart rate while sleeping?
Anything below 30 could be considered too low and anything above 50 could be considered too high.
Is resting heart rate the same as sleeping heart rate?
These are different things. Jean says your sleeping heart rate will typically be lower than your daytime resting heart rate.
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