Explaining HRV & Why it’s a useful metric – 30 Factors that affect HRV
Heart Rate Variability (HRV) is a measure of the variation in time between consecutive heartbeats.
It reflects the balance between the sympathetic and parasympathetic nervous systems and provides insights into overall health and wellness.
Generally, higher HRV is associated with better health outcomes, while lower HRV is associated with increased risk of various health issues.
Later on in this article, we will explore 30 factors that can affect HRV, both positively and negatively
But first let’s help you understand exactly what Heart Rate Variability is…
Things to know:
1) HRV is measured in milliseconds (ms)
2) HRV refers to the timing between R Intervals (see above)
If it were constant it would indicate low HRV – due to low variability.
If it is variable it would indicate a higher HRV – due to it being variable.
3) HRV is highly individualised
A high HRV for one person can be a low HRV for another.
You should establish your own baseline to track what’s relevant for you – see end of article
Now lets take a look at the 30 factors that can affect HRV, both positively and negatively.
Factors that Decrease HRV:
• Illness – Decreases HRV (Physiological stress)
• Aging – Decreases HRV (Reduced parasympathetic tone)
• Stress – Decreases HRV (Sympathetic activation)
• Smoking – Decreases HRV (Cardiac irritant)
• Caffeine – Decreases HRV (Cardiac stimulant)
• Alcohol – Decreases HRV (Cardiac depressant)
• Poor Sleep – Decreases HRV (Sleep deprivation)
• Inflammation – Decreases HRV (Cytokine release)
• Chronic Pain – Decreases HRV (Stress response)
• Anxiety – Decreases HRV (Sympathetic activation)
• Depression – Decreases HRV (Reduced parasympathetic tone)
• High Blood Pressure – Decreases HRV (Autonomic imbalance)
• Diabetes – Decreases HRV (Autonomic dysfunction)
• Heart Disease – Decreases HRV (Autonomic dysfunction)
• Obesity – Decreases HRV (Inflammatory state)
It’s interesting to see the overlap between HRV and wellness activities.
Another way of looking at this could be immediate gratification results in decreased HRV.
Factors that Increase HRV:
• Exercise – Increases HRV (Improved fitness)
• Sleep – Increases HRV (Recovery)
• Meditation – Increases HRV (Relaxation response)
• Breathing exercises – Increases HRV (Parasympathetic activation)
• Yoga – Increases HRV (Relaxation response)
• Music – Increases HRV (Relaxation response)
• Cold Exposure – Increases HRV (Stress response)
• Acupuncture – Increases HRV (Modulation of autonomic nervous system)
• Gratitude – Increases HRV (Positive emotions)
• Social Support – Increases HRV (Reduced stress)
• Sauna – Increases HRV (Parasympathetic activation)
• Deep Tissue Massage – Increases HRV (Reduced muscle tension)
• Tai Chi – Increases HRV (Mind-body connection)
• Spending Time in Nature – Increases HRV (Reduced stress)
• Laughter – Increases HRV (Positive emotions)
Hopefully now you have a better understanding of what HRV is and how it is affected.
Continue reading for further understanding of HRV and How to use it.
How accurate are smart watches for tracking HRV?
Google/AI answer: “While some studies have found that certain smartwatches can provide reliable HRV measurements compared to ECG, others have reported less accuracy.”
My answer: “Even if smartwatches aren’t 100% the accuracy of an ECG they can provide valuable insight into the state of your health and wellness”
How do you track HRV?
So here are my actual HRV scores for the last week upto to today (as of writing this).
Let me make sense of this through detailing my weeks activities:
Sun 25 to Weds 01 – Working 12 hour shifts.
Sun 26 – Drank 250mg caffeine (100mg more than usual) +
20 min Jog in 30C heat
Mon 27 – High thirst & apetite – illness onset
Tues 28 – Illness full intensity & Didn’t go into work
Weds 01 – Illness improved but still sick – did go to work
Thurs 02 – Still sick but got rest
Fri 03 – Still sick but improving
So we can see from Saturday my HRV was dropping and would have been optimal to reduce stress (work) and stimulants (caffeine) both of which decrease HRV.
I would say Sundays run helped boost my HRV (80ms on Monday) but ultimately the illness won out given all the ticks in the Decreaase HRV section vs the lack of ticks in the Increase HRV section.
As I subjectively began to improve (symptoms decreased) I could see that my HRV score reflected this (which I have seen in other instances also).
If you are looking for help navigating your own health journey then I encourage you to reach out to me to see what can be optimised