"Basically I came home pretty much frustrated from China, after a very sad season," the seven times Formula One champion said at Ferrari's Christmas Party at the Maranello factory last weekend.

"In my mind I didn't feel like a holiday, as I did in previous years because I thought I deserved holidays," added the German.

"This year I feel I don't really deserve any holiday and (wanted to) keep working, being a lot together with the team, communicate and check the situation where we are and finally be in the car."

Schumacher had been champion for the previous five seasons, winning 13 of the 15 races in 2004, while Ferrari won the last six constructors' titles before their domination ended abruptly this year.

The 36-year-old won just once in 2005, a hollow victory in the six-car U.S. Grand Prix after the seven Michelin-equipped teams withdrew for tyre safety reasons at Indianapolis, and finished a distant third overall.

Renault's Fernando Alonso [Images] won seven times and the 24-year-old Spaniard took more than twice as many points as Schumacher.

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Schumacher will return to testing in Jerez on Thursday, the first time since 1998 that he has gone back to work between the last race of the season and New Year.

He said he was eager to experience the new V8 engine and assess the team's state of preparation.

"We have our test drivers running, we have (Brazilian) Felipe (Massa) running but I just want to be in the car and drive it myself and see what's happening," he said.

"I feel very fresh and very motivated, very hungry...I feel it would be too late to wait until some time in January until I will be in the car," said Schumacher.

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