Stress causes poor sleep. And research shows that insomniacs do have elevated cortisol in the middle of the night, when cortisol should be at its lowest. Conversely, poor sleep causes stress. But more recently, researchers have discovered that good quality sleep the night before a stressful event can protect you from negative health consequences. Even though you will still encounter stressful events in your life, good quality sleep gives you better brain chemistry to deal with those events.

 Sunlight and darkness trigger the release of hormones in your brain. Exposure to sunlight is thought to increase the brain’s release of a hormone called serotonin. This is associated with boosting mood and helping a person feel calm and focused. At night, darker lighting cues trigger the brain to make another hormone called melatonin. This hormone is responsible for helping a person feel sleepy and go to sleep.

 Before sunrise the rays that are refracted by the atmosphere operate a greater influence on the brain. At sunrise the sunrays that are coming in a straight line are influencing the respiratory organs and our sensibility. With the approach of noon the same rays influence our digestive system. That is why the healing effect of the sun energy is different: before sunrise – to stimulate the brain nervous system, from 9 to 12 – to strengthen the stomach. In the afternoon, generally the sunrays possess an insignificant healing effect. The reason for such a difference lay in the different absorption capacity of the Earth and of the human system

 We have to consider the following rule: we are a part of the earth system and when the latter absorbs the energy, the human system absorbs it too, and vice versa. That is why the first sun rays are the most active. Then the human system is most receptive towards the sun energy. There is always more prana or vital energy in the morning than at noon. At this time the system absorbs the biggest quantity and the most powerful positive energy.

 Brahma muhurta (time of Brahma) is a period (muhurta) one and a half hours before sunrise or more precisely 1Hr 36 Mins before sunrise. i.e. 96 Minutes = 2 Muhūrta or 4 Ghaṭīkā,and each Muhurta lasting for 48 minutes. Literally meaning "The Creator's Hour", it is traditionally the last phase or muhurta of the night and is considered an auspicious time for all practices of yoga and most appropriate for meditation, worship or any other religious practice.

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