I know from experience that jet lag can be a very annoying condition. Eastbound travel across the Atlantic, for example, takes place only through the night; you might get on the plane at 10 pm travel for ten hours, and arrive thinking it’s 8 am, but the clocks say it’s four pm. You didn’t sleep much on the plane and you then have to stumble through several hours, eventually lying down exhausted but oddly aware that it’s not yet bedtime. Flying west is generally held to cause the condition less than flying east. Staying healthy, and possibly dosing yourself with melatonin to change your body’s natural sleep schedule may help in a more useful way.