Everything You Should Know About Heart Rate Variability (HRV)

If you think your heart beats at a regular interval like a metronome, think again.

We have a natural variability in the spacing between our heart beats. This phenomenon is

called heart rate variability, and HRV for short. It says a lot about our bodily systems,

which is why athletes and health enthusiasts alike have been so interested in this, and

why you should be too. Simply put, HRV is a measurement of the balance between your

parasympathetic and sympathetic nervous systems. These two systems make up the autonomic nervous

system, which handles about 90% of the body’s involuntary functions.

The sympathetic nervous system is what kicks into gear when we are stressed or in danger.

We sweat, our heart rate goes up, and the interval between our heart beats goes down.

We produce norepinephrine, and our body is primed to either fight or flight.

The parasympathetic nervous system

is pretty much the opposite, and it functions like a brake by disabling the sympathetic

nervous system. Dubbed the rest and digest response, it activates when we are in a relaxed state,

and engages processes such as the production of saliva and peristalsis. It uses acetylcholine

to make the heart beat slower, and with greater intervals. When in balance, they therefore

produce high HRV through a more variable heart rate. The more variable your heart rate, the

more you are able to readily respond to your environment and switch gears between these

two systems. HRV is used as a health marker. It generally decreases with age. High HRV is

an indication of cardiovascular health, fitness, willpower, calm and positive emotions, and

your ability to handle stress and exercise. Low HRV is related to inflammation, chronic

stress, chronic pain, depression, cancer and low emotional flexibility. HRV values have

actually been used to predict injury recovery and cancer outcomes. One sports scientist

has been able to predict very accurately the point differential in wrestling matches based

on pre-match HRV readings. Elite athletes use daily HRV measurements to adjust their

training regimen and prevent overtraining. There is also an interesting link between

HRV and willpower. HRV is a huge predictor of persistence and self-control, and it increases

when exerting self-regulation. This mechanism is called the pause and plan response. By

changing our physiology, we can manipulate our HRV, and the way we do this, is through

breathing, and what is called resonance frequency breathing. Combining this breathing with a

biofeedback device to monitor your HRV in real time is called HRV training. By slowing

down your breathing, you can activate the parasympathetic nervous system and raise your

HRV, which causes your heart rate and blood pressure to synchronize with your respiration,

resulting in a state that the HeartMath institute calls coherence. The optimal rate of breathing

that produces coherence and increases your HRV the most, differs from individual to individual,

and is called your resonance frequency. For most people it will be around 5.5 seconds.

Doing minimum 10 minutes of this breathing every day, you can develop the skill of producing

a state of coherence at any given moment. Activating this state, you can get into the

zone so to speak, and increase your performance for single actions such as swinging a golf

club, or hitting a baseball. HRV training has shown to be incredibly beneficial for

kids with overactive sympathetic nervous systems and resulting belly aches. After a few weeks

of daily training, they show massive improvements in their baseline HRV and are able to function

much better. Some autoimmune conditions related to the gut have been helped by this type of

training as well, as our gut permeability is closely related to our parasympathetic

nervous system. Other benefits of HRV breathing include pain management in conditions such

as fibromyalgia and chronic muscle pain. It can help with asthma, depression, hypertension,

and self-control. It’s also great for stress management. Around 20% of people will feel

sleepy from following this breathing rhythm, which makes it a great tool for falling asleep

quickly at night. If you want to experience this state of coherence, I've created two

videos for you to practice this breathing. One is suitable for the morning or day and

looks like this, and one is made for night time with minimal blue light, if you'd prefer

doing it right before bed. The interest in HRV has increased substantially the past decade,

and several consumer technologies have emerged to help measure your personal HRV metrics.

The most accessible way to accurately measure your HRV is to get a polar heart rate chest

strap, and connect it with an app called EliteHRV. EliteHRV also sells a device called CorSense

which you stick a finger into, to measure your HRV. The previously mentioned HeartMath

Institute has created the emWave Device, and the Inner Balance sensor, to provide biofeedback

as you perform HRV training. The Oura Ring is a sleep tracker that shows you an average

HRV value from your night of sleep. I’ve added links to these in the video description

below, and also links to a few more resources on HRV if you’re interested in learning

more about the subject. Thank you for watching this video. Subscribe if you’d like to see

more Mind Drip videos. And don’t forget to try out the HRV breathing, by clicking

on one of the videos here on the right side.