Part 3: Sleep and Heart Rate Variability
Stress is our response to the daily patterns of life. It affects us emotionally, physically, and behaviorally. Our central nervous system does not differentiate between physical or mental stressors, nor does it differentiate between positive or negative stress.
The right amount of stress can be a positive force that can support us to do our best and to keep us alert, ambitious and energetic. However, too much stress, can make us tense, tired and anxious.
One of the fundamental components of recovery and ensuring you perform optimally is through monitoring 3 areas of your health. As we have mentioned, this includes, heart rate variability, resting heart rate and sleep.
Why Should You Monitor Sleep?
Sleep is a major contributor to stress resilience. Sleep is absolute rest and a time when the body and mind are offered a chance to filter and file away the day. It’s also a time for the body and mind to shut down and recover. Without this optimal experience, we wither away.
Over the last 40 years, our society has gone from sleeping 7-9 hours per night, to an average of 5-6.7 hours per night. When we do not sleep long or well enough, our bodies do not get the full benefits of sleep, such as muscle repair and memory consolidation. More importantly, the prolonged reduction of adequate sleep can lead to illness, disease and injury.
Sleep is regulated by two body systems: sleep/wake homeostasis and the circadian biological clock. It is important to keep a regular sleep schedule and allow plenty of time for quality sleep, allowing these two vital biological components — the sleep/wake restorative process and the circadian rhythm — to help us perform at our best. When this is altered or irregular sleeping habits are introduced, this can lead to poor productivity and poor health.
How Does Sleep Relate to Improving HRV?
A key role is played by the autonomic nervous system (ANS), whose modulation regulates cardiovascular functions during sleep onset and different sleep stages.
The influence of sleep on central sympathetic nervous system (SNS) activity can be better understood by using the major method applicable to humans, known as HRV (heart rate variability), specifically looking at the low frequency (LF) component of heart rate variability (HRV).
We spend one third of our lifetime sleeping, yet the majority of people do not honor its importance. The interaction between ANS and sleep is somewhat complex, but simply put, any changes in ANS regulation can profoundly affect sleep onset and sleep homeostasis and, on the flip side, modifications of physiological sleep can alter autonomic cardiovascular regulation. Research has showed that sleep is a complex phenomenon in which autonomic cardiac control fluctuates between sympathetic and parasympathetic predominance, mainly according to the transition to different sleep stages. Deep sleep is essential for recovery and reducing neuro-inflammation caused by intolerable volumes of stress.
How Can You Track Your Sleep?
Understanding your sleep phases and cycles is the best place to start monitoring your sleep. The first phase is light sleep, followed by deep sleep and a dream state referred to as REM-sleep. A full sleep cycle lasts about 90 minutes and is normally repeated several times each night.
With the use of technology, almost anything is possible these days. There are many sleep trackers out there; such as, FitBit, Jawbone and most commonly used is “Sleep Cycle.”
I have been using this for nearly 2 years. Sleep Cycle is an iOS app that watches your sleep habits from your nightstand in order to help wake you up at the best possible time of the morning. Tracking your sleep can offer you insights into how well you sleep based on your movements.
Using a sleep tracker app with your HRV are two great ways to monitor your nervous system, and can validate your good habits and offer you a glimpse into some areas you should modify to improve your health and keep you accountable towards your goals.
Get it here: Sleep Cycle