Jet lag by route

A common rule of thumb is about one day of adjustment per time zone crossed, a little faster going west than east. Holding a fixed wake-up time and getting daylight at the right time of day speeds it up.

Going east you have to fall asleep and wake up earlier than your body wants, which is hard. Going west you stay up later, which is much easier — so westward jet lag usually clears faster.

A fixed, unmissable wake-up time at your destination, combined with bright light at the correct end of the day. The wake-up time anchors the clock; light shifts it.