Heart Rate Variability (HRV) and Sleep: Does Sleep Deprivation Impact HRV?

The required amount of sleep varies from person to person, but most adults need 7-9 hours per night to function optimally. A lack of sleep can negatively impacts your physical and mental health, weaken your immune system, increase your risk of heart disease, and even shorten your lifespan. It has been found that Heart Rate Variability (HRV) is lower during sleep compared to when an individual is awake, and it decreases further as a person progresses from light to deep sleep. Additionally, research has shown that HRV is influenced by the quality and duration of sleep. Poor sleep quality and insufficient sleep have been associated with lower heart rate variability, while adequate sleep has been linked to higher HRV. Some studies have also suggested the inverse relationship, stating that HRV may also be a predictor of sleep quality, with lower HRV being associated with poor sleep quality and higher HRV being associated with better sleep quality.

(Ref.Link)

What is a Good HRV During Sleep?

The adult heart rate is typically between 60 and 100 beats per minute when at rest. As you fall asleep, your heart rate slows down to its resting rate, the body’s core temperature decreases, and other muscles relax. In deeper sleep stages your resting heart rate may decrease by about 20 to 30 percent. Heart rate variability (HRV) changes as you progress through different sleep stages. During non-rapid eye movement (NREM) sleep, overall HRV generally decreases, although the variance between individual beats can increase. In contrast, during rapid eye movement (REM) sleep, overall HRV increases while beat-to-beat changes decrease. HRV is often used as a marker of sleep quality and has been linked to various health outcomes. Poor sleep quality, high sleep onset latency, and the use of sleep medication have all been associated with higher heart rate and lower HRV. On the other hand, higher HRV during wakefulness has been tied to better sleep efficiency and overall sleep quality. Sleep deprivation and certain sleep disorders, such as obstructive sleep apnea, have also been linked to changes in HRV.

Can a lack of sleep affect HRV?

Poor sleep quality can disrupt the balance between the sympathetic and parasympathetic nervous systems, leading to an imbalance in HRV. Chronic sleep deprivation has been linked to a decrease in HRV, which may increase the risk of certain health conditions such as cardiovascular disease and diabetes. Conversely, getting enough quality sleep can improve heart rate variability and overall health. It is important to prioritize sleep and practice good sleep hygiene to help maintain healthy HRV levels.

People with insomnia experience elevated sympathetic activity both during night and day. When the sympathetic nervous system is stimulated, the heart rate increases and the HRV decreases. During sleep deprivation, this sympatho-vagal balance shifts towards sympathetic dominance. Insufficient sleep impairs the nervous system’s ability to shift into rest mode, even at night and despite feeling exhausted. HRV is used as an indicator to determine sleep quality. According to a study published in 2013, higher HRV during wakefulness is linked to better sleep quality, and lower HRV indicates inadequate sleep quality.

How to Increase your HRV During Sleep 

There are several ways to increase heart rate variability (HRV) during sleep:

1. Practice relaxation techniques such as deep breathing, meditation, or yoga before bed to help reduce stress and improve sleep quality.
2. Establish a consistent sleep schedule by going to bed and waking up at the same time every day.
3. Avoid caffeine, alcohol, and heavy meals before bedtime, as they can disrupt sleep.
4. Create a comfortable sleep environment by keeping the room dark, cool, and quiet, while using a comfortable mattress and pillows.
5. Engage in physical activity during the day to improve sleep quality and HRV.
6. Avoid screens for at least an hour before bedtime, as the blue light emitted by screens can disrupt the production of melatonin, a hormone that helps regulate sleep.
7. Consider trying natural remedies such as melatonin or valerian root to help improve sleep quality.

HRV and Sleep: How Are They connected?

There is a complex, two-way relationship between the autonomic nervous system and sleep. The activity of the autonomic nervous system (ANS) influences both your ability to fall asleep and how well you sleep throughout the night. In turn, the quantity and quality of your sleep has an impact on how well your autonomic nervous system works in managing stress, regulating your cardiovascular activity, and regulating hormones and physiologic function. Here are some key points to understand about how the ANS functions and how HRV changes while sleeping:

• During sleep, both the parasympathetic and sympathetic nervous systems are active, and their levels of activity fluctuate throughout the night.
• Falling asleep is linked to increased parasympathetic activity. You will be in ‘rest and digest’ mode to drift off into sleep.
• In the Non-REM (Rapid eye movement) stage, the parasympathetic system(resting) continues to dominate. Non-REM sleep is associated with higher HRV.
• In REM (Rapid eye movement)  sleep, the sympathetic system(stimulating) becomes more active. HRV is usually low and variable in this stage.
• Disturbed sleep or waking up through the night activates the sympathetic system which raises your blood pressure and heart rate while decreasing HRV.
• A typical night of 7 hours of sleep consists of 4-5 sleep cycles, with each cycle containing non-REM and REM sleep stages. During sleep, ANS activity is complex and dynamic, and HRV is continuously shifting.

Poor quality or insufficient sleep causes a decrease in HRV which can lead to increased risks for hypertension, diabetes, obesity, and other cardiovascular diseases. To ensure optimal HRV, it’s important to get enough quality sleep every night by limiting blue light exposure before bedtime, avoiding caffeine late in the day, creating a relaxing bedtime routine, keeping your bedroom cool and dark, and practicing mindfulness or meditation before bedtime. If you suspect that there may be underlying medical causes for your insomnia or difficulty sleeping through the night speak with your doctor about potential treatments or medications that might help.

Finally, pair your new understanding of how sleep affects your HRV with the use of a heart monitoring device to know exactly how you’re impacting your heart. Purchase the revolutionary Frontier X2 and be on your way to a healthier tomorrow.

Stay on top of your heart health while pushing your limits with the Frontier X2, a heart rate monitor that captures high-quality ECG on your chest during exercise.

Frequently Asked Questions on HRV and Sleep :

What are the effects of sleep deprivation?

Sleep deprivation activates the sympathetic nervous system (stimulating) both during sleep and daytime. This leads to irritability, stress, an increase in heart rate, and a decrease in HRV. 

How can I measure my HRV?

There are several ways to measure HRV, including the following:

• Wearable devices: Many fitness trackers and smartwatches have built-in HRV sensors that can measure your HRV throughout the day.
• Smartphone apps: There are numerous apps available for both iOS and Android devices that use the phone’s camera or a separate chest strap to measure HRV.
• ECG/EKG machines: Electrocardiograph (ECG or EKG) machines, which are used to measure the electrical activity of the heart, can also be used to measure HRV. These machines are often used in hospitals or medical offices, but there are also portable ECG/EKG devices that can be used at home.
• Finger sensors: Some devices use sensors that attach to your finger to measure HRV       

How can I get more sleep?

You can get more sleep by following a daily sleep routine, using a comfortable mattress, and by incorporating meditation and yoga into your daily routine.

How does sleep deprivation affect HRV?

Yes, sleep deprivation lowers HRV as the sympathetic system is activated.

Other Heart Health Topics To Explore:

Stress impact on Women’s Heart | Paroxysmal Atrial Fibrillation | Arrhythmia Causes | Aquatic Exercise for Heart Health | Yoga for Heart Health | Heart Health | Cardiac Arrhythmia | Heart Palpitations | Running Heart Rate Zones | Heart Rate Monitor

Frontier X2:

Smart Heart ECG Monitor in USA | ECG Machine Price in India | Best Heart Rate Monitor UK