The BEST Vital Sign you’re not looking at: HRV – Heart Rate Variability
When it comes to providing objective data about our own health and fitness, we are often our own worst enemies. With the need to constantly do more, sleep less, train more, eat less, push harder, work longer, get more done……we find ourselves thinking we’re invincible and impervious to the stressors we place on our bodies and minds. We expect our bodies to be able to adapt to chronic cumulative stress without any adverse affects to our wellness. If someone asks, how often do you tell them you’re overworked, deprived of sleep, over-trained, underfed and stressed beyond repair????
Being reflective and honest about your state of stress if the first step to identifying your own limitations and what is holding you back from reaching your goals (in and to of the gym). The ability to provide quantitative biofeedback has shown to help control physiological responses to stress and is an effective way for athletes/clients/weekend warrior to learn how to control mental and physical responses to stress. This is NOT easy to do, and often the degradation of our coping mechanisms are masked by what we think is “normal”. e.g. tired, irritable, hungry, feeling “blah” or just making it through the day, day after miserable day.
This is why ECG (electrocardiography) biosensors like a Heart Rate Monitor have been able to capture more comprehensive date about overall health, wellness and performance by measuring both Heart Rate (HR) and Heart Rate Variability (HRV).
Heart Rate (HR) is an average measurement of beats-per-minute that varies by activity level, constantly increasing and decreasing depending on the demand of the body. While desired, a low resting heart rate itself should NOT be considered a leading overall indicator of heart health.
Before we dive into HRV, let’s have a cardiology 101 lesson:
Your heart rate has two major working systems: electrical and mechanical. An electrical impulse is sent though the heart to tell the muscles to contract and push blood out. The mechanical component you can feel (your heartbeat and your pulse), the electrical can only be measured with an ECG device ( a cardiac monitor or a Heart Rate Monitor). Below is an image of what to might see if you hooked yourself to a cardiac monitor to assess the ELECRICAL system in your heart.
Take note of the R wave – it’s important!!!! The R wave is the first upward deflection after the P wave and part of the QRS complex. The R wave indicates ventricular depolarization aka the electrical impulse which makes your ventricles pump blood out of the heart creating your pulse. Your HR monitor will look at your “R wave” intervals (space between each R wave) to estimate your average heat rate. The higher your heart rate, the closer your R to R interval…. The lower your heart rate, the wider your R to R interval Is.
Now…. What is HRV and why is it so important?
Heart Rate Variability (HRV), on the other hand, is a measure of each heart beat’s variation over a period of time. The heart monitor is able to assess the very minuscule difference in R to R interval, as shown below and takes an average over a period of 2-5 minutes.
SO, your HRV is an assessment of your heart’s ability to accelerate and decelerate quickly and efficiently to meet the body’s immediate needs. You want this…. You want your heart rate to increase in times of need (run away from danger or fight your way to the front of the donut line), and slow down to focus on other bodily functions (like digesting the 7 plates of food you ate at the all you can eat buffet… and/or the dozen donuts you just snatched up).
………..With us so far?????
An HRV can vary based on a number of factors, but traditionally the HIGHER the average HRV means the “healthier” you are.
…..And now I just lost you.
BUT YES, YOU WANT YOUR HRV HIGH!!!!! BUT WHY would you want your heart rate bouncing around instead of beating like a metronome???
Well, to simplify a very difficult and almost mind-numbing concept.. you want a healthy tug-of-war between the two systems that control your heart rate (and HRV). Your sympathetic nervous system (that adrenaline you get during fight or flight) and your parasympathetic nervous system (rest and digest) are always in a tug-of-war battle.
You sympathetic nervous system is your gas pedal and is responsible for many changes including accelerating your heart beat; your parasympathetic nervous system is your brake, slowing things down and allowing for some rest and recovery after being on the gas pedal.
You want these two systems to be in a healthy tug-of-war, so they both get used and keep each other in check. What you DONT want is for them to be equal (a very boring tug-of-war match) or even worse, trying to drive a car with your foot on both the gas and brake. We want variation in your Heart Rate, aka HIGH heart rate variability (HRV).
In general, a high HRV indicates dominance of the parasympathetic response, the side of the autonomic nervous system that promotes rest, relaxation, digestion, sleep, and recovery. (GOOD)
NOW, the MILLION-dollar question? WHY should you care?
AWARENESS. You can’t fix the problem if you haven’t identified it. A body in a state of chronic stress will be resistant to any progress you’re trying to make due to the constant bombardment of of catecholamine’s and glucocorticoids (including cortisol) which have detrimental affects on your body.
Aside from the acute affects of increased sympathetic response (high blood pressure, high heart rate, high blood sugar, decreased peristalsis/digestion), long-standing stress promotes even more negative effects.
Sustained High levels of catecholamines/glucocorticoids like Cortisol are directly linked to:
- Blood Sugar Imbalance and Diabetes
- Gastrointestinal Problems (including poor nutritent uotake and Decrease Secretory IgA (SIgA) which serves as the first line of defense in protecting the intestinal epithelium from toxins and pathogens)
- Weight Gain and Obesity with Decreased Muscle Mass and Bone Density
- Cardiovascular Disease
- Fertility Problems
(see these items listed in detail here: http://www.todaysdietitian.com/newarchives/111609p38.shtml)
So you can see how going to the gym to get your 5th workout in after a restless night which you tried to counteract with your gallon of Red Bull, will only FURTHER your stressed state.
Seeing a low or downward trending HRV might be a great indication that you should take a day (or two, of 7) OFF to rest, recover, rejuvenate and relax OR start to prioritize your lifestyle to promote stress-reductio!
And once you focus your efforts on reducing your stress, increasing parasympathetic tone, and bring your body (and it’s hormones) back to homeostasis you should get RESULTS! After all – That’s what you’re looking for: Weight Loss, Increased Strength, Hormonal Balance, General Improved Demeanor, a GREAT night sleep! (Not to mention reducing risk for stress-related illness, such as cardiac problems, asthma, and diabetes).
Typical HRV ]Scores
(Please remember the trend is more important than an individual number)
80-90 High HRV Score
70-80 Moderate HRV Score
60-70 Fair HRV Score
< 60 Poor HRV Score
Want to increase your HRV???
- Focus on Parasympathetic Nervous System Activation: actively focus on recovering and stress reduction (yoga/medication/breathing techniques/massage)
- Sleep More (Be an animal in bed! Preferably a Koala that sleeps 22 hours a day)
- Eliminate foods and supplements that are adding to the problem (anything which causes inflammation in the gut will affect your parasympathetic system and lower your HRV). Eat a variety of macro/micronutrients from Whole Foods, Drink Water, find a good probiotic, take NATURAL stress reducing and anti-inflammatory supplements and STOP taking stimulants (energy drinks/pre-workouts and whatever you from that guy in the supplement store).
- Improve your conditioning, specifically by increasing your aerobic stamina. Mitochondria(the energy power plants of our cells) transform energy from food into cellular energy. Exercise increases the number of mitochondria improving your body’s ability to produce energy. The more mitochondria you have and the better they function, the higher your HRV will be.
The Master himself, Coach Eugene Teo