Jetlag is actually caused by disruption of your 'body clock', a small cluster of brain cells that controls the timing of biological functions (circadian rhythms), including when you eat and sleep. The body clock is designed for a regular rhythm of daylight and darkness, so it's thrown out of sync when it experiences daylight and darkness at the 'wrong' times in a new time zone. The symptoms of jetlag often persist for days as the internal body clock slowly adjusts to the new time zone.

By following a carefully timed program of light and dark at the times your body clock is most responsive, you can quickly reset it to the new time zone. Instead of taking a week or more to adjust to an intercontinental journey, you can become fully adapted to the new time zone in just one or two days.

A successful time zone shift depends on knowing the exact times to seek and avoid bright light. Exposure to light at the wrong time can actually make jetlag worse. The proper schedule for light exposure depends a great deal on specific travel plans. Taking a night flight to Tokyo, for instance, creates very different demands than a day flight to Los Angeles. Personal variables are important too; if you're a 'night owl' you'll typically need a different schedule to a 'lark'.

Acording to the Jet Lag Calculator as i have travelled east from Madrid to Sydney, I should avoid light between 06:30 and 11:30 then switch to seek bright light until 14:30. Ok, i haven´t done any of this. Today i should avoid light between 03:30 and 08:30 then switch to seek bright light until 11:30. Ok, same shit, i don´t think i will be able to do this. And here i am, can´t sleep and waiting some hours for a meeting with this guys, and designing in flash a hotel template you can see finished above. Enjoy.