Temperatures at trackside in Sepang can reach 50 degrees Celsius and sitting in a fire-proof safety suit next to a high performance engine means it is even hotter for the drivers.

"It's like having to do some physical exercise in a sauna and, unless it was having sex, I cannot imagine why anyone would want to do anything in a sauna," said Coulthard, a veteran of all seven previous Sepang races.

"You just get on with it because you are focused, but in any circumstance in normal life you would be admitted to hospital with severe dehydration."

It is not just the sheer heat that makes driving here so difficult, according to his fellow Briton Jenson Button [Images].

"It is very tough because even on the straights it is difficult to breathe," said the Honda driver. "And because it is so humid here and when you are trying to get some proper air into your lungs it is difficult. It is really, really hot air."

The heat means that along with the designer sunglasses and serious sports watches in evidence at all races, the must-have accessory for the paddock player at Sepang is the humble half-litre plastic bottle of mineral water.

"You definitely need liquids in the race and before the race," said Button. "I normally drink about five litres in the morning before the race. It makes a massive difference.

"I didn't have a drink here a couple of years ago and I was so dehydrated that I was shivering and getting cold in the car and then you start to lose your eyesight."

Ralf Schumacher, perhaps anticipating another tough weekend for his Toyota team after their miserable season-opener in Bahrain last week, said a lot depended on how well a driver's car was working.

"There are years when I have had a difficult car to race here and it was tough," the German said. "There were other years when it was totally easy and so it depends on the whole package.

"If you have a nice running car then it is not a real problem. But if you have a lot of work to do in the car, then it is a problem usually."

Drivers have small containers on board with them, something Button thinks is advisable even if world champion Fernando Alonso [Images] professed to have gone the whole of last year's race without so much as a sip.

"I know he won the race, but he didn't too good afterwards, did he?," Button said.

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