Lewis Hamilton admitted too much partying affected his performances during a disappointing 2011 Formula One season and vowed he would be fully focused when the new championship begins in Australia this weekend.
The Briton finished fifth in the drivers' championship last season, and behind McLaren teammate Jenson Button.
The 2008 world champion said his struggles could be attributed to a "knock-on effect" from his pursuits away from the track, but insisted those days were behind him.
"Last year quite a lot of times I went out and enjoyed myself thinking that these things don't affect you but in actual fact they do, they have a knock-on effect," Hamilton said, according to Sky Sports.
"It takes you two days to recover, you miss two days of training and your mind is somewhere else when you get to the race."
The season-opening Australian Grand Prix will be held Sunday at Albert Park, Melbourne.
