MANAMA, April 4, 2008 (AFP) - World championship leader Lewis Hamilton hopes a rigorous training vacation in the heat of Thailand will pay off in the searing heat of the Gulf at the Bahrain Grand Prix on Sunday.

The McLaren driver said he had been training hard in Thailand since the last race in Malaysia.

"My trainer and I, and (Force India driver) Adrian Sutil, we went away to Thailand. We did a little bit of travelling. We went to Bangkok and to Phuket and a couple of other islands," said Hamilton.

"It was so nice to have another driver with you doing the training, to see the competitiveness and make it fun."

Hamilton added that he had been playing a lot of sports, including tennis, golf, basketball, and beach volleyball, and also did a lot of swimming.

"We did a lot of running in the heat obviously and it is like double the work of anywhere else," he went on.

"And we did a lot of kayaking and swimming, too. I´m not usually keen on going out in the deep sea, but I got over it. I overcame one of my fears, which was good.

"I definitely don´t like white sharks, that´s for sure! I guess it is the unknown - just not knowing what is below you. I like to go scuba diving, so for me being under the water is a completely different thing from floating on top.

"You see all those Discovery Channel things when the bloody shark jumps up and eats whatever is floating on the top. I just don´t fancy being in that position."

Meanwhile, the 23-year-old Briton joined with close friend Nico Rosberg to share some happy memories of previous visits to Bahrain.

Hamilton and his old German pal Rosberg recalled sharing a podium at the Sakhir circuit in 2004.

But both were determined to ensure that their current ambitions with McLaren Mercedes-Benz and Williams are realised with successful results again this weekend.

"I have had some great races here dating back to 2004 if I am not mistaken when Lewis and I were actually standing on the podium after the race," said Rosberg.

"It was the Macau-Bahrain Challenge at that time so even then it was great for us, we had great times. I have had many great races here."

Rosberg won his GP2 title in Bahrain in 2005 and said: "That was fantastic and it was one of the most important steps in my career on my way to Formula One."

Hamilton said: "It´s a really cool circuit and I really do enjoy it. I´ve always had a great time here in the last few years, especially the first time I came here when I thought my career was over and somehow I managed to pull a miracle out of the bag.

"That is when Nico and I were on the podium. But last year was great for me here, too. From here, I was leading the world championship, but this year, coming here, I obviously want to try and go one better. And I think we are in a good position to do that."