From GMM

More than 70 per cent of Formula 1's eighteen confirmed drivers for 2009 have lost weight since the end of last season.

That is the finding of the Austrian portal sportnet.at, which published a ranking of who has reacted with the most rigour to the debut of heavy KERS systems this year.

With the car-plus-driver minimum weight remaining static at 605kg, the need for drivers to be as light as possible is more crucial this year.

In Monday's edition of Der Spiegel news magazine, Williams' Nico Rosberg called on the FIA to introduce a separate minimum weight for drivers, with overly light competitors forced to attach handicap weights to their seats.

The biggest weight-losers this winter have been Robert Kubica, Fernando Alonso, Mark Webber, Kimi Raikkonen, Giancarlo Fisichella and Sébastien Bourdais, who reportedly all lost between 3 and 7 kilos.

Reigning world champion Lewis Hamilton is said to have fallen from 68 to 66kg, while Rosberg, Kazuki Nakajima and Sébastien Buemi all also dropped 2 kilos.

Nelson Piquet, Heikki Kovalainen and Jarno Trulli dropped 1 kilo apiece, while Adrian Sutil, Felipe Massa, Sebastian Vettel, Timo Glock and Nick Heidfeld did not lose weight.