This article was written by our trainer Maria Vittoria Zulli
Biofeedback training for HRV is an intriguing approach to enhancing self-awareness and control over physiological processes, particularly HRV. This technique empowers individuals to actively influence their autonomic nervous system, promoting better well-being and potentially improving performance. A recent meta-analysis of 24 studies revealed that HRV biofeedback reduced self-reported stress and anxiety with a large effect size (Goessl et al., 2017).
Training to enhance Heart Rate Variability (HRV) has gained interest in recent years due to its potential benefits for both physical and mental well-being. HRV biofeedback promotes the maintenance of a physiologically efficient and highly regenerative internal state, characterised by reduced nervous system instability and increased overall coherence and harmony. This psychophysiological state, known as physiological coherence, is conducive to healing, emotional stability, and optimal performance.
Increasing HRV for increased brain health and performance
A high HRV indicates that there is a lot of variability in the time between heartbeats, which suggests that the autonomic nervous system is functioning well and is in balance.
When HRV is high, brain imaging studies have shown increased activity in areas responsible for cognitive control, attention, and emotion regulation (Arakaki et al., 2023).
This suggests that a flexible autonomic system, reflected in HRV, supports better brain function. Conversely, a low HRV indicates that there is less variability in the time between heartbeats, which may suggest that the autonomic nervous system is imbalanced, and it is often linked to stress or certain health conditions. Low HRV is also associated with altered brain patterns in regions related to emotion processing and cognitive performance (Mather et al., 2018).
Higher HRV is associated with enhanced emotional self-regulation. A meta-analysis has demonstrated that greater HRV is linked to improved top-down self-regulation, known as the ability to regulate behavioural, cognitive and emotional processes (Holzman et al., 2017). HRV biofeedback has also proven effective in reducing stress and anxiety in various populations, including general adults, individuals with anxiety disorders, and young adults experiencing stress (Henriques et al., 2011; Goessl et al., 2017). Studies have shown that even brief HRV biofeedback interventions for individuals under stress significantly reduce state anxiety, enhance mindfulness, energise positive emotions and induce a state of relaxation (Prinsloo et al., 2013).
Regarding cognitive improvements through HRV training, research has shown that HRV biofeedback leads to increased psychophysiological coherence, which is associated with improved homeostatic regulation and changes in the brain’s information processing capacities (McCraty et al., 2004). These changes result in performance enhancements and improvements in cognitive processes such as focused attention, discrimination, and motor skills.
Overall, while the exact nature of the relationship between HRV activity and brain activity is still being studied evidence suggests a direct correlation between the two.
In simple terms, a healthy HRV coincides with a brain that is more capable of focused thinking, managing emotions, and optimal performance. This emphasises the close connection between our heart and brain, affecting our overall well-being and cognitive abilities.
Understanding Biofeedback Training for HRV
Biofeedback involves using sensors and monitoring devices to provide real-time information about physiological functions like heart rate and HRV. The key concept is that when people receive immediate feedback about their body’s responses, they can learn to modify these responses voluntarily.
How it works:
Measurement: During biofeedback training for HRV, sensors are attached to the body, usually on the finger or ear, to monitor heart rate and intervals between beats. The monitoring devices provide real-time information about heart rate and HRV.
Visualisation: The real-time data is converted into visual or auditory feedback. This might be displayed as waveforms on a screen or through sounds that change based on HRV.
Breathing techniques: many biofeedback systems for HRV training emphasise controlled breathing. The goal is to synchronise breathing with the changes in the visual or auditory feedback.
The key concept is that when people receive immediate feedback about their body’s responses, they can learn to modify these responses voluntarily.
Benefits and mechanism:
Awareness: Biofeedback training creates awareness of how specific thoughts, emotions, or relaxation techniques impact HRV. This awareness helps individuals understand their body’s responses better.
Self-regulation: with practice, individuals learn to influence their HRV consciously. This can increase parasympathetic activity, promoting relaxation and overall well-being.
Stress reduction: By gaining control over their physiological responses, individuals can use biofeedback training to reduce stress, anxiety and regulate emotional responses, leading to improved focus, better decision-making and enhanced emotional resilience. This, in turn, positively affects HRV.
Increasing HRV is a holistic process. It involves nurturing both your body and mind through mindful choices. By integrating these practices into your daily life, you create an environment that is suitable for achieving better well-being and performance.
Get to know the HRV physiological measures
HRV can be measured using various methods and is used as a tool to monitor and improve physiological and psychological health. HRV measurements are usually analysed as R-R intervals (RR), heart rate (HR), standard deviation of the normal-to-normal interval (SDNN), root mean squared successive differences (RMSSD), and the percentage of the number of changes in successive normal sinus intervals that exceed 50 ms (pNN50). In the frequency domain, HRV measures are analysed as high frequency (HF), low frequency (LF), very low frequency (VLF), and ultra-low frequency (ULF).
Overall, RMSDD and HF reflect vagal inputs to the heart. The vagus nerve is a fundamental component of the parasympathetic branch of the autonomic nervous system. While baseline vagal input is constant, the degree of stimulation it exerts is regulated by a balance of inputs from sympathetic and parasympathetic divisions of the ANS, with parasympathetic activity generally being dominant. Vagal tone is frequently used to assess heart function and is also helpful in assessing emotional regulation and other processes that alter, or are altered by, changes in parasympathetic activity (Diamond et al., 2011).
Increased vagal functioning is associated with a lower heart rate and increased HRV.
For instance, studies have shown that higher HF, RMSSD, or pNN50 indicate higher vagal functioning, while decreased levels suggest lower vagal activity (Shaffer et al., 2017).
The higher the vagal tone, the better executive cognitive performance, as well as better emotional regulation and social functioning (Thayer et al., 2009).
Click here to read the summary of research in the field and full references