McLaren Formula One driver Lewis Hamilton of Britain stands next to a McLaren MP4-12C car during a promotion event ahead of the Singapore F1 Grand Prix September 19, 2012. The Singapore F1 night race will take place on September 21-23.  [Photo/Agencies]

Hamilton will need to draw on all his strength and fitness to vie for top honours in Singapore, a race the majority of drivers regard as the toughest of the season both physically and mentally.

"The temperature is pretty intense. For example, today, just getting in my suit and driving in the car, sweating like crazy," the 27-year-old said.

"In the race, it will be just the same. You have thermal underwear on, you have a suit, you have a balaclava, gloves, and a helmet, and you're in a cockpit and the humidity, so there's no cold air coming into the cockpit, and then just the focus, driving a car is massively physical."

Then comes the recovery period.

"It takes a couple of days to wind down from a race. For us, because we train so much, some races are physically easy. Monza (Italy) wasn't really a stress for me, so the next day I was able to train," he added.

"But here, your liquid levels and natural vitamin levels are low and you need at least a day of relaxing to get them back up."

Hamilton displayed little emotion on the podium after his Monza victory two weeks ago, fuelling speculation in the paddock that a rumoured switch to Mercedes next season was becoming more likely.

However, the Briton explained his lack of joy was more to do with a personal matter than anything concerning his future driving plans.

"We buried my aunt that week, so she was constantly on my mind, she had been on my mind for particularly the last three weeks or so, so it has been a tough time for the family, and just had a lot on my mind," he said.

"It was nothing to do with being unhappy. Trust me, I was happy. I just won a grand prix I had never won before."