Beating Jet Lag
Jet lag is caused by a number of things, including crossing time zones and breathing in recycled air on the plane. To avoid the worst effects, try changing your watch to the time zone of your destination as soon as possible during your flight, keep drinking lots of water and avoid alcohol, coffee, tea and fizzy drinks (which contain caffeine).
On reaching your destination, try to get your body used to the local time. For example, if you arrive at your destination and it is early evening, try to keep active until it's time to go to bed. Go outside for a short walk to allow the natural daylight to reset your body clock.
If you arrive in the middle of the day try and have a short nap, then resume the rest of the day as you would had you not travelled, so eat an evening meal, take in the daylight, then go to bed as close to bedtime as possible. This will all ensure you get a reasonable night sleep at nighttime, which will help reset your body clock.
During cramped long-haul flights, some passengers have an increased risk of suffering from a DVT (Deep Vein Thrombosis). This is the clotting of blood, usually in the lower legs. Stretching exercises during your flight can help - and you should also consider buying flight socks, designed with graduated compression to help improve blood-flow through the legs.