The Science behind Pranayama

Prana (life force) ayama (control)

When your prana leaves you, you die. We feel tired after we finish a long run, we feel tired after we study for 3 hours at a stretch. This is the simplistic definition of energy, prana.

Hatha Yoga Pradipika (the Yogic bible) says as long as the prana is not controlled, the mind can never be in our control. Pranayama is an ancient science, to enable control of your mind, by regulating your breath. Various types of pranayamas have different effects on the body, mind, and spirit. The physiological effect is that it improves lung efficiency and eventually benefit the entire body. The mental effect is that cools down your mind and improves your ability to think. Multiple studies have shown that increasing efficiency of the lungs, increases life span. 

Pranayama, Lung Capacity, Heart Rate and Basal Metabolism:

Lung Capacity and utilisation: An adult lung capacity is 6000ml. A human being on an average breathes in and out about 500ml of air with every breath. I.e., breathes 500ml of air and breathes out 500ml of CO2. This basically implies that a human under-utilises the lung capacity by a factor of 10. On an average, a human breathes in 12 to 15 times a minute. Hence the minimum requirement of air for the body is 500ml *12 = 6000ml. The brain registers this as a requirement for the body.

Heart Rate: Generally speaking, the heart rate goes up with every breathe in and it goes down with every breathe out. At rest, this up and down can barely be noticed. A healthy at rest heart rate is about 72 and can vary between 60 and 90 between person to person. In most cases lower the heart rate, healthier you are.

Basal Metabolism: Rate of energy (Energy required per unit of time) required by a human body to continue working when at rest.

When a yoga practitioner practises pranayama, especially cooling Pranayamas she breathes in long and breathes out even longer, (sometimes in the ratio of 1:2) the below happens.

A)      The volume of every breath will be more than the “at rest” volume of 500ml. It could go as high as 4500ml if there is a significantly long breath. This implies that the lung capacity utilisation increases. Deep breathing also implies that she now has to take fewer breaths per minute. From 12-15 breaths to possibly 4-8 breaths a minute, maybe even lesser.

B)      As a generic rule, our heart rate increases when we breath in and decreases when we breath out. This implies that for every breathe in, the heart gets ‘stressed’. For every breathe out, our heart relaxes. During the practise of pranayama, especially when she breathes out longer, the heart stays relaxed longer as compared to “at rest” scenario. In a minute, at rest, we breathe in 30 seconds (heart stressed) and we breathe out 30 seconds (heart relaxed). During pranayama, in that same period we breathe in 20 seconds (heart stressed) and breathe out 40 seconds (heart relaxed)

The longer she practises pranayama in a day, the more regular she is in her long-term practise, the following would happen

·         Breathes per minute, longevity and health

o   During pranayama the breaths per minute reduce to 8-10 per minute, sometimes down to 4-6 per minute. The longer the practise continues, the longer the brain gets the signal that the body can function with a lower frequency of breathes. The result is that the “at rest” breathes per minute reduce. The monks who practise pranayama and meditation for hours together are known to take not more than 6-8 breathes a minute “at rest”. Whales, Elephants, Tortoise all breathe 4-8 times a minute. All of them are known to live a much longer life. Cats, Dogs breathe 15-30 times a minute. They live shorter. There is very clear data which points to this correlation.

·         The brain gets continuous signals that the lung capacity can be increased beyond its 500ml per breathe and over a period of time increases to 600-700 ml per breath. Lesser frequency of breathing implies the lungs get stressed less

·         The heart then has to pump lesser, lesser effort is required. This combination of reduced no of breathes, increased volume of O2 per breathe, results in reduction of at rest heart rate further from the previous base of 72.

·         This results in digestive system requiring lesser food as lesser effort needs to be expended.

·         Lesser food we consume, the pancreas, the liver needs to work lesser.

·         All of this implies that the body would require lesser effort to remain at rest.

·         This implies the basal metabolism reduces.

In most traditional exercises, the result is that the metabolism rate increase, which increases the effort on all organs of the body and hence requiring additional nourishment and hence requiring additional food and energy to support the body

The practise of Hatha yoga and specifically pranayama has exactly the opposite objective. Reduce metabolism, especially basal metabolism, with the focus on reducing stress on body organs. This also implies they remain healthy, and most importantly work extremely efficient. The yoga view is that this results in longer, happier life. Lots of data available to prove it

All these changes take a tremendous amount of time and come with continuous practise. But the results are unmistakably amazing.