HRV Explained
Heart rate variability or HRV is the physiological phenomenon of the variation in the time interval between consecutive heartbeats in milliseconds. A normal, healthy heart does not tick evenly like a metronome, but instead, when looking at the milliseconds between heartbeats, there is constant variation.
HRV is regulated by the autonomic nervous system (ANS), and its sympathetic and parasympathetic branches.
The Sympathetic Nervous System controls your body’s “fight or flight” reactions in response to internal or external stressors. It stimulates blood glucose (to fuel your muscles), pupil dilation (to see tigers better), slows digestion/peristalsis (to focus energy on the present danger), and increases heart rate (to ensure adequate blood circulation to run or fight). The SNS is ideally activated to overcome short term stress situations such as running from a tiger or fighting an intruder.
The Parasympathetic Nervous System controls your body’s “rest and digest” responses and is associated with recovery. Parasympathetic activation conserves energy, constricts pupils, aids digestion, and slows heart rate. The PSNS is meant to help build for the long term and is needed to grow faster, stronger, and healthier.
Heart Rate Variability is an accurate, non-invasive measure of the ANS and the balance between the SNS and PSNS branches.
The HRV level changes naturally from day to day, based on the level of activity and amount of stress.
The natural interplay between the two systems can be disrupted, and the body can get stuck in a sympathetically dominant fight state, with low HRV and high stress hormone levels, even when the person is resting.
This is very consuming on the body and can result in various mental and physical health problems.
What Do HRV Readings Mean?
Higher resting-state HRV scores signify the ability of the body to activate the Parasympathetic “rest-and-digest” response. Higher heart rate variability is correlated with:
• Increased fitness level
• Better health
• Better resilience
• Youthfulness
• Willpower
• Calm, positive emotions
Lower resting-state HRV scores signify an activated Sympathetic “fight-or-flight” response or suppressed Parasympathetic activity. This can indicate the body’s inability to engage recovery mode or an exhaustion of recovery capacity. This can be a temporary response to a previous day’s hard workout or poor night of sleep. Or this can be a chronic response to stress that results in reduced health and increased risk of disease. Lower resting-state HRV is tied to:
• Reduced fitness level
• Poor health
• Increased disease risk and inflammation
• Increased biological age
• Negative emotions
• Increased anxiety and depression
HRV At ESP
We use Elite HRV for recording and monitoring HRV.
The app lets you tag your HRV measurements with the important things going on in your life and then helps you analysis the results and provides daily HRV-based guidance.
Our athletes synchronise their HRV reading into TP so we can get a full picture of their response to training stress.
As a coach / athlete we need to monitor HRV and the bodies corresponding nervous system response to insure we balance the correct amount of training stress and recovery for the body to adapt as planned. HRV is fantastic as it takes into account other stressors on the body as well as training stress.
Not only do we use HRV for adapting the training and recovery for our athletes but it is also a vital tool for helping athletes recover from sickness or injury by fine tuning the timing and intensity of returning to training.
As we collect more data and source more training on HRV we will be able to fine tune and individualise your training even more than we currently do.
For an interesting podcast on how HRV is being used with Elite athletes check out this:
Olympic Training And Elite Endurance
Recording Devices
To measure HRV an accurate and convenient heart rate monitor will be necessary. HRV data is quite sensitive, so not all heart rate monitors will work.
Our preferred options to work with Elite HRV are the CorSense finger sensor or accurate Bluetooth Heart Rate Straps such as the Garmin or Wahoo Tickr.
Currently wrist based devices such as wearable watches are not accurate enough to be used with Elite HRV.
Information from Heart Rate Variability: A Deeper Metric by Elite HRV
