Basic relaxation pose or śavāsana measurably restores all the indices of stress to a healthful balance including blood pressure respiratory rate and brain weight it allows for an increase in parasympathetic tone in the nervous system thus facilitating better digestion and assimilation of food improving fertility and speeding healing. In addition, studies show improved immune system function when a person regularly practices relaxation.

We override all this intelligence that bubbles out of the belly, that's our interoception - our sense of internally what's going on in us - we ignore it, we brush it aside.

śavāsana is when we lie flat on the floor with props, I like lots of props... and what we consciously do is we... are stopping the input that's under our control. Now if you're lying in śavāsana you may hear a car go by or an airplane or something but what's under our control in that moment is we're not moving the body and we're not looking at anything and we're not doing anything and we're not studying anything and we're just letting the body be. We're not even asking it to go to sleep, we're not asking anything of the body. We are instead listening to what the body is telling us for 20 minutes and that is one of the most healing things we can do on virtually every level of our existence.

When we are practicing śavāsana, it takes us into a light non-REM easily rousable sleep state. We might not even realise we’re asleep. We have these lower frequency brainwaves that are dominant. They’re called theta waves. What happens when we practice śavāsana or another restorative pose for 20minutes*, it puts us in this theta brainwave dominant state that recharges us. It refreshes our mental acuity and energy because of the dominant brainwaves. We’re slowing down the brainwaves and shifting the brain and our nervous system into a flow state.

Rest and sleep are different physiological states, we need both of them. In sleep, we work through the entire repertoire of brain waves from blast bursts of gamma waves, to alpha, beta, theta, and delta waves etc. When we’re awake, we're in a state of higher amplitude brain waves, lower frequency (beta brainwaves). When we drop into śavāsana, we're still in a state of higher brain waves, lower frequency, but they're not as high and they're slower (theta and alpha brainwaves). So your brain isn’t running around. We need this to recharge.

Functional MRI and EEG studies measuring brainwave activity, show that restorative yoga practices from śavāsana to yoga nidra, lead to shifts in brainwave patterns that produce positive neurophysiological shifts. Meaning you get out of your limbic system - your reptilian brain - which is a big driver for your sympathetic nervous system arousal and your perception of safety. You move into a state of parasympathetic imminence, and it's also improves something called our neuroplasticity. We're going to have more and more flexible connections in our brains that are going to improve our capacity to process information. And it's as easy as setting up in śavāsana for 20 minutes* a day.

* The reason why it needs to be 20 minutes is because of physiology. That's your neuro-fizz. We need a minimum of 15 minutes to make the shift from our awake, alert, active state to a slower brain wave state.