If you search the internet for a definition of normal respiratory rate for an adult, you may find the answer to be either 12 to 16 or 12 to 20 breaths per minute (BPM).
Minute Ventilation (MV), which is the product of Breath Per Minute (BPM) and Tidal Volume (TV), is one of the important breathing metrics to monitor. For example, a MV of 15 Litres at rest is associated with very sick people, and it is a breathing volume contributing to hyperventilation, which is at least in part responsible for a range of chronic diseases, such as asthma, high blood pressure, heart disease, diabetes, cancer, etc.
Now let’s come back to our original question “What is the Optimal Respiratory Rate at Rest?” Also, does it depend on age, sex, height, weight, race, etc?
There appears a lot of medical research has been undertaken in the last decade on breathing techniques and their potential clinical benefits. This is in the context of the breathing retraining method for reduced breathing and slow breathing known as Buteyko Breathing pioneered by Dr. Konstantin Pavlovich Buteyko started back in the 1950s, when he discovered that over-breathing is the root cause of asthma. Buteyko Breathing has been demonstrated to be very effective in treating a range of chronic disorders, particularly asthma, as well as a wide number of profound health benefits.
Recent research has also found that breathing can affect heart rate, in particular, during inhalation, it makes the heartbeats faster, and during exhalation, it makes them slower. In the physiological term, this is called Heart Rate Variability (HRV).
Higher HRV is more desirable because it indicates a healthy heart and overall healthy physiological functioning, including a more balanced parasympathetic-sympathetic functioning. Research has shown that HRV peaks when the breath rate is 5.5 or rounded off at 6 BPM, and this is common in healthy humans.
Coincidentally, research has also found further benefits at 6 BPM, such as:
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- Most efficient gas exchange at the lungs
- Increase of blood pressure fluctuation leading to significantly lower average blood pressure for the same cardiac output.
Based on the above, it is logical to conclude that a 6&6 breathing pattern should be adopted by most people to not only gain the benefits of maximum HRV but also to ensure no over-breathing occurs. Therefore, instead of trying to breathe at the optimal respiratory rate, we should try to breathe with an optimal breathing pattern, i.e., to breathe at 6 BPM AND with 6 litres MV at the same time.
You could try to breathe the 6&6 pattern at any time at rest, but especially do it via meditation before sleep to gain an immediate additional benefit of better sleep quality.
Now you may wonder how you could know your MV, assuming you could manage the BPM by a watch.
The great news is that Aimwell’s AYO BT+ Breathing Measurement and Breathing Exerciser can do just that, plus many more functions to train for healthy breathing.
Your physiological norm of Minute Ventilation is proportional to your weight, which can be calculated from 6 Litres for a 70 Kg adult. For example, if you weigh 100 Kg, your physiological norm of Minute Ventilation is 100/70 * 6 = 8.6 Litres.
The image on the right is a screenshot from the App of AYO BT+ during a 20-minute meditation. By monitoring the BPM and MV from the App during the meditation, one can control the tidal volume to breathe towards the 6&6 healthy breathing pattern.
In summary, optimal respiratory rate alone is not sufficient to ensure the best health outcome, and your physiological norm of Minute Ventilation must be included together to ensure you do not over-breathe,
Aimwell AYO BT+ Breathing Measurement and Breathing Exerciser is an effective tool for you to measure your breathing volume and train for the optimal breathing pattern.