Any way you look at it, a long-haul flight is no walk in the park.

On a recent flight to Asia, it took six hours of flying just to get from Toronto to Anchorage for a one-hour stop. Then another 11 hours in the air to Hong Kong.

On each leg, Cathay Pacific Airways played a video on staying healthy in the air. In it, a calm, carefree guy strolls through an idyllic park stretching his arms high over his head and doing ballet-like knee lifts and foot swivels while walking toward a lounge chair beside a babbling brook. All the while, a narrator urges passengers strapped to their seats to keep moving to avoid cramps, blood clots, fatigue and jet lag.

And while the advice is good, it is somewhat impractical on most flights I've taken lately.

If you stretch your arms over your head in an airliner, you risk rapping your knuckles on the ceiling or smacking the person in the seat next to you. March briskly around the cabin and you'll draw the suspicion of the air marshals, not to mention the folks who are trying to sleep.

And a series of recent events are conspiring to make doing what you need to do to stay healthy in the air even more difficult. New bans on liquids mean water you want to carry on might get confiscated. Cost-cutting has scrapped food service and weight-saving programs have tossed out pillows and blankets and siphoned off the amount of water taken on board.

Meanwhile, flights are getting longer. Air New Zealand is introducing service from Vancouver to Auckland in November — a 15-hour, non-stop flight. That's more than twice as long as a flight from Toronto to London or Paris, and three times longer than a flight from Vancouver to Montreal.

No matter how long your flight may be, some tips from the pros who do such long hauls regularly will help you arrive in better shape.

Meet Winter Yau, Toronto-based in-flight service manager for Cathay Pacific Airways, who does a round trip across the Pacific every week. She's seen the exercise video hundreds of times and she says that from personal experience, getting up and stretching regularly makes people feel better both on the flight and afterward.

Get moving

Unlike some North American airlines that shoo passengers back to their seats regularly, Ms. Yau says Hong Kong-based Cathay encourages passengers to get up and move around at intervals during the flight.

Most passengers who did the stretches in the video when the airline first started showing it a few years ago were elderly ladies, she says. Now it seems that younger passengers have become less shy about getting active in the aisles, or as they wait for the lavatory.

Ten minutes on your feet every couple of hours will get your circulation going and can reduce problems of fatigue, aches and cramps, Ms. Yau finds.

If people haven't left their seats by the middle of the flight, she encourages them to get up and move around, she says. Too much time sitting in one position leads to swelling of legs and feet, body aches, and the potential risk of more serious circulatory problems.

Drink up

The air on a plane is dryer than a desert, as Dr. David Powell, chief medical officer for Air New Zealand, knows well. He recommends passengers have a glass of water every hour in the air to prevent fatigue, headache, irritability, and dry skin. This is especially important if you are also drinking alcohol or coffee, both of which make dehydration worse.

However, it's getting tougher to follow that advice, as most North American airlines are cutting meal and beverage services. For instance, on a recent Miami to Toronto flight on a domestic airline, overzealous airport security staff confiscated a bottle of mineral water I had bought in the waiting area after going through security screening. Then, because there was no meal service on the four-hour flight, no water was offered — I was told the airline is cutting back the amount of water it takes on board to save weight.

Most airlines should still be carrying lots of drinking water, though, so ask, and ask often. And if you don't receive, complain. We're talking life support here, not privileges.

Carriers that specialize in long hauls recognize this. Flight attendants on Cathay Pacific are required to make water runs through the cabin with pitchers and cups every hour between meal services, Ms. Yau points out. And in business and first class, a large bottle of mineral water is placed in a cup holder at each seat, she adds.

Get some support

Support stockings are a trick of the trade for flight attendants. They help prevent the pooling of blood in the lower legs and feet that happens in a pressurized cabin on flights lasting more than four hours, Ms. Yau says. A particular risk is deep-vein thrombosis, a condition in which a blood clot forms in the legs and then breaks off and blocks blood flow in the lungs.

Studies in healthy people have shown that wearing compression stockings minimizes the risk of developing deep-vein thrombosis after long flights, so yeah guys, support stockings (call them manny-hose) might be a good idea for you, too, Dr. Powell says. But get the kind of compression or isotonic stockings made specifically for this purpose and available at department stores and medical supply shops. Avoid regular socks if they have very tight elastic bands at the top, and don't sit for long periods with your legs crossed, because this can cramp circulation in the veins.

Stay limber

Self-massage on legs and feet helps keep blood flowing and reduce fatigue, Ms. Yau says.

Use your thumb and forefingers to massage your temples and the back of your neck and shoulders with circular motions.

Take off your shoes, if possible, and do the same to the soles of your feet. Also, roll your feet against the floor and rotate your ankles left and right as you sit.

Cushion the blow

Ms. Yau recommends putting a spare pillow behind your back or under your legs at the knee to cushion the pressure on the back of the legs. Pillows are disappearing on many airliners, so I personally always take my own inflatable pillow. I fill it only a quarter full of air, for cushioning rather than stiffness.

Advice from the experts

For all you road warriors, Ms. Yau has advice based on personal experience that can help make flying as trouble free as possible.

"The most important thing is discipline. I don't try to go out to shop or eat after a long flight. It is important to relax your body and your mind," she says.

A healthy diet can help combat the stresses of long-haul flights. Yau eats a diet high in fibre and fruits and drinks green tea, saying the regimen seems to keep her skin from drying and aging. She also takes a 400-International-Unit vitamin E supplement before a flight, explaining that its antioxidant qualities seem to combat fatigue.

Powell also supports taking a vitamin E supplement, and has some other tips for adjusting to the new time. One involves melatonin, a natural hormone that some say can help adjust sleep cycles to reduce jet lag, although at least one study has suggested it has no effect on jet-lag sufferers. Until recently, you needed a prescription for melatonin, but now you can buy it over the counter in Canada, although anyone taking any supplement should check with a doctor first to make sure it doesn't interact with other medications or affect other health conditions.

Although research on the effects of melatonin is still ongoing, Powell says there is scientific evidence that taking one tablet (3 milligrams) before hitting the hay in the first three or four days after a flight can hasten adjustment to the new time zone.

Another thing that helps reset your body clock is to make sure you don't exacerbate the problem by going right to bed if it's not the regular sleep time at your destination, Dr. Powell recommends. "Upon arrival it is important to give the body as many cues as possible to the new [time] zone cues."

Avoid daytime sleep, other than a brief nap if required, and take a walk to get sunlight, even on a cloudy day, he advises. No matter what your stomach may be trying to tell you, have meals at the appropriate local times, he adds.

Après landing

Ms. Yau is also an advocate of exercising after a flight. Attendants are urged to so some arm and leg stretching before bedtime and stretch out their spines by arching their backs a number of times. It can help you sleep like a baby, she says.

Of course, you should do this in the privacy of your hotel or home and not on the floor of the plane.

And whether the flight is 15 hours or only one, attitude is everything. "Stay positive," and divert your attention with music, a video or a book, Ms. Yau advises. Time goes faster when you're having fun.