Close the blinds and sit still to enjoy the ride, suggests a new pan-European study on high-speed tilting trains. A walk to the buffet car may exacerbate the train's tendency to confuse our senses, producing motion sickness.
Queasy travellers should take note, with tilting trains spreading across Europe and scheduled for arrival in the UK from 2002.
Since their development some 30 years ago, the compensatory tilt of high-speed trains has been known to produce motion sickness in up to 30% of passengers. This, coupled with technical difficulties, halted the trains' development in the UK, although it was pursued elsewhere in Europe and the tilt reduced.
The further spread of these trains into Europe threatens a situation in which "unacceptable numbers of passengers may become ill," a consortium of European scientists now suggest
Passengers' behaviour can influence their suffering, the team show for the first time. The team observed people on test rides of tilting trains across two winding European mountainous routes - France's Massif Central and the French-Italian Alps.
Walking around a train seems to be particularly nauseating, making 5 out of 21 subjects and 1 experimenter vomit. Studying a map could also induce illness. Lowering the blind to obscure the heaving horizon was the most important prevention factor, the team found.
Several European countries, including Italy, France and Germany already run tilting trains. In July this year, Virgin Trains unveiled a £1-billion plan to introduce 53 of the 140-mph 'Pendolino' trains on the UK's west coast London to Glasgow line from June 2002. They hope to cut travel times by a quarter on the meandering route through the Lake District and Scotland.
"We will be looking at [motion sickness] carefully," says Virgin Trains spokesman Jim Rowe. "We don't believe it will be the same problem as it was 20 years ago," he says, adding an assurance that the new trains will have blinds.
Conflicting messages to the senses cause motion sickness, explains neuroscientist Michael Gresty, a consortium member working at Imperial College, London. Compensatory tilting keeps passengers upright so trains can take curves faster, but we still see the horizon moving up and down.
"Sensors on the butt say we're sitting upright but our vision says no, we're tilting rapidly," says Gresty. In conventional trains, the body feels the curve too and motion sickness is rare.
Measures that minimize the conflict - such as pulling the blinds to block the view - reduce the sickness. "It's well known on boats, that you sit at the centre and look to see the horizon," agrees Johan Forstberg of the Swedish National Road and Transport Research Institute in Linkoping. "This is one of the first reports on the influence of activities on motion sickness."
Since tilting trains were introduced in Sweden in 1990, steps have been taken to reduce the problem, Forstberg explains - by reducing the trains' tilt and adjusting the curve of the track. What's more, Swedes are aware of the problem, so very susceptible people stick to conventional trains, says Forstberg. "Maybe it will come as a surprise," he says of the UK's inexperienced tilting travellers.