It matters in which direction you go.

Going west, you'll be sleepy very early in the evening, but then no one is really stoping you from going to bed at 7 PM and staying in it for twelve hours straight until 7AM (you probably will wake up around 2-3 AM, but there's nothing else to do at that time, so you'll probably stay in bed just out of boredom). As the result you adapt pretty quickly.

Going east is much harder: you can't fall asleep at night, and then during the day you have things to do, so you end up sleep deprived for quite long.