I love the British Airways site on sleep and air travel. There are free podcasts for download; information about jet lag; advice for coping with jet lag; and other aspects of air travel and sleep issues covered. The best thing is it is all free!
One of my favorite parts of the site is the jet lag calculator - you answer a few questions, it provides advice on lessening the effects of jet lag. I threw in some sample times to see what kind of advice I would get for a flight with a 6 hour time difference.
The podcasts are done by British Airways' resident Dr. Sleep, Dr. Chris Idzikowski, and include topics with titles such as The business side of sleep.
British Airways has a jet lag calculator - by answering a few simple questions regarding your recent or planned flights, it doles out advice on the best things to do to minimize jet lag.
This is what happened when I plugged in a sample time difference of 6 hours:
"What time do you normally wake up in the morning?" 8 am
"Do you usually sleep well?" no
"What time is it in the place you are visiting (if you have returned home from your journey please enter the current time at the country you visited)?" 6 pm
"What time is it at home?" 12 noon
This is the advice I was given based on those answers:
"Day 1
Avoid light between 9:00 am to 11:30 am
Seek light between 11:30 am to 14:00 pm
Day 2
Avoid light between 6:00 am to 8:30 am
Seek light between 8:30 am to 11:00 am
Seeking light
The advisor has suggested the optimum time to expose yourself to light. Light is important because it is one of the primary cues that the body clock uses to maintain its link with the outside world.
When it comes to seeking light, any kind of light will do. Daylight is best, but if its not available, simply switching on a bedroom light is sufficient to help you minimise the effects of jet lag.
Avoiding light
Avoidance of light at certain times is also an important cue to the body clock to help you recover more swiftly from the effects of crossing time zones.
Avoiding light can be achieved by drawing the blinds or curtains in the room you are in, or wearing an eye mask. If theres nothing else you can do, then simply wearing dark glasses will help.
Meals and exercise
In addition, adjusting your exercise and main meal times to your new time zone will help to synchronise your body clock sooner."
Easy to follow advice, and a fun tool to boot, this is the gem of British Airways' website!

