What's controlled breathing?

Breathing is linked with mental functions and in the eastern tradition it is considered essential for reaching the meditative state of consciousness. The breath is called “Prana,” which means both “breath” and “energy” (i.e., the conscious field that permeates the whole universe). “Prana-Yama” (“the stop/control,” and “the rising/expansion of breath”) is a set of breathing techniques which directly and consciously regulate parameters of respiration (e.g., frequency, deepness, inspiration/expiration ratio). While Pranayama is primarily related to yoga practice, it is also part of some meditative practices and recently used on its own as a controlled breathing practice.

How healthy slow breathing really is?

Various studies agree that slow breathing techniques:

• Modify activity of the Central Nervous System resulting in increasing the Heart Rate Variability and Respiratory Sinus Arrhythmia
• Increase alpha and decrease theta powers (EEG studies) associated with improving vigor-activity and reducing anxiety, depression, anger and confusion when considering psychological/behavioral outcomes (Fumoto 2004; Yu 2011).
• Results in the psychological/behavioral outputs such as increased comfort, relaxation, pleasantness, vigor and alertness, and reduced symptoms of arousal, anxiety, depression, anger, and confusion
• Decrease the anxiety levels (Gruzelier 2014; Lovibond and Lovibond 1995, assessed with the Depression, Anxiety, and Stress Scale).
• Increase the oxygenation of brain (Critchley 2015); with the 5 breaths per min resulting in more oxygen in brain compared with 10b/m.
• Result in relaxation (Lehrer 2003, Lin 2014), together with increased ease and comfort (Edmonds, 2009), positive energy and pleasantness (Van Diest, 2014)
• Enhance interactions between autonomic, cerebral and psychological flexibility, linking activities related to both emotional control and well-being.

Results of breathwork in practice

Paced breathing sessions at 6 breathing per minute with different inspiration/expiration ratios result in the strongest perceived ease and comfort level (Edmonds 2009) and are associated with an increased subjective perception of relaxation (Lin 2014). In the Smith Relaxation States Survey 2001, 6 b/min breathing was characterized, at a subjective level, by higher positive energy, higher pleasantness, and lower arousal levels when compared to 12 b/min breathing.

In the study done by Kharya (2014) participants practiced slow breathing for 150 days (5 days a week, 30 min a day). Their Life Style Management improved significantly as the result of this practice.

Fumoto (2004) found that voluntary abdominal breathing (Zen Tanden Breathing) at 3–4 b/min significantly reduced alpha peak at 10 Hz at the EEG (electrical activity in a brain test) and induced significantly higher alpha2 activity (10–13 Hz) in the parietal areas as compared to spontaneous breathing. When asked in the review, participants reported improved vigor-activity (Profile of Mood States, McNair 1971) and reduced anxiety (Spielberger et al., 1983).

Additionally, Yu (2011) study found significantly increased level of oxygenated haemoglobin and the mood states showing reduced Tension-Anxiety, Depression-Dejection, Anger-Hostility, and Confusion.

Breathing and the state of consciousness

Science agrees that at the EEG level, slow breathing techniques are associated with reductions in theta and increases in alpha activity. A recent systematic review dealing with the neurophysiology of mindfulness (Lomas 2015) interprets this as an index of an increased inwardly directed attention (i.e., to the self-regulated act of breathing). The progressive sensory deafferentation occurring during slow breathing techniques induces an inward directed attentional shift. Therefore, the deepening of meditative state allows the emergence of theta rhythm to play a fundamental role in altering the state of consciousness.

The more we focus on slow breathing the deeper our meditation practice is. The deeper the meditation is the more we are aware of the self, our bodily sensations and of our thoughts.

Bottom line

Slow breathing techniques when practice daily help us to reduce stress, anxiety and strengthen our brain and heart. Studies found enough evidence of increased emotional control and psychological well-being in healthy people during slow breathing techniques. In particular, there is a reliable association between and increase of heart rate variability power (leads to have a greater cardiovascular fitness and more resilience to stress), increase of alpha brain waves (stimulates creativity and minimizes depression) and decrease of theta power (better sleep), induced by slow breathing techniques at 6 b/min, and positive psychological/behavioral effects.

References: 

Edmonds W. A., Kennedy T. D., Hughes P. A., Calzada P. J. (2009). A single-participants investigation of the effects of various biofeedback-assisted breathing patterns on heart rate variability: a practitioner’s approach.

Fumoto M., Sato-Suzuki I., Seki Y., Mohri Y., Arita H. (2004). Appearance of high-frequency alpha band with disappearance of low-frequency alpha band in EEG is produced during voluntary abdominal breathing in an eyes-closed condition. 

Yu X., Fumoto M., Nakatani Y., Sekiyama T., Kikuchi H., Seki Y., et al. . (2011). Activation of the anterior prefrontal cortex and serotonergic system is associated with improvements in mood and EEG changes induced by Zen meditation practice in novices.

Gruzelier J. H., Thompson T., Redding E., Brandt R., Steffert T. (2014). Application of alpha/theta neurofeedback and heart rate variability training to young contemporary dancers: state anxiety and creativity. 

Lovibond S. H., Lovibond P. F. (1995). Manual for the Depression Anxiety Stress Scales. Sydney, NSW: Psychology Foundation.

Critchley H. D., Nicotra A., Chiesa P. A., Nagai Y., Gray M. A., Minati L., et al. . (2015). Slow breathing and hypoxic challenge: cardiorespiratory consequences and their central neural substrates.

Lehrer P. M., Gevirtz R. (2014). Heart rate variability biofeedback: how and why does it work?.  

Lin I. M., Tai L. Y., Fan S. Y. (2014). Breathing at a rate of 5.5 breaths per minute with equal inhalation-to-exhalation ratio increases heart rate variability.

Edmonds W. A., Kennedy T. D., Hughes P. A., Calzada P. J. (2009). A single-participants investigation of the effects of various biofeedback-assisted breathing patterns on heart rate variability: a practitioner’s approach.

Van Diest I., Verstappen K., Aubert A. E., Widjaja D., Vansteenwegen D., Vlemincx E. (2014). Inhalation/Exhalation ratio modulates the effect of slow breathing on heart rate variability and relaxation. 

Kharya C., Gupta V., Deepak K. K., Sagar R., Upadhyav A., Kochupillai V., et al. . (2014). Effect of controlled breathing exercises on the psychological status and the cardiac autonomic tone: sudarshan kriya and prana-yoga.

Fumoto M., Sato-Suzuki I., Seki Y., Mohri Y., Arita H. (2004). Appearance of high-frequency alpha band with disappearance of low-frequency alpha band in EEG is produced during voluntary abdominal breathing in an eyes-closed condition.

McNair D. M., Lorr M., Droppleman L. F. (1971). Manual for the Profile of Mood States. San Diego, CA: Educational and Industrial Testing Services.

Spielberger C. D., Gorsuch R. L., Lushene R., Vagg P. R., Jacobs G. A. (1983). Manual for the State-Trait Anxiety Inventory (Form Y1 – Y2). Palo Alto, CA: Consulting Psychologists Press.

Lomas T., Ivtzan I., Fu C. H. (2015). A systematic review of the neurophysiology of mindfulness on EEG oscillations. Neurosci. Biobehav.

US National Library of Medicine, National Institute of Health, 2018, How Breath-Control Can Change Your Life: A Systematic Review on Psycho-Physiological Correlates of Slow Breathing