Heidfeld reports no back issues

Last weekend in France, the BMW Sauber suffered a repeat of the pains that forced him to pull out of testing at Silverstone last month.

But despite the British track's bumpy surface, Heidfeld said he was feeling fine and was also pleased with his day's work.

"In the first session and at the beginning of the second one everything went well," said Heidfeld, 15th quickest.

"Later my car was not so good, although we didn't change much. It was difficult to drive, so we have to figure out why. Even over the bumps here in Silverstone I don't have any problems even with my back."

Teammate Robert Kubica, who was absent from the Silverstone test last month following his Montreal crash, also enjoyed a positive day. He finished down in 13th place.

"I would say it was quite an easy day," he said. "There is a little bit of set-up work to be done for tomorrow for free practice and qualifying, so we have to analyse today's data, but we had no problems so it was quite good. Although I missed the test on the second lap my times were already good, so this was not a big issue.

"Maybe I could have prepared for my race set-up a little better if I had run in the last test session here, because the track has changed quite a lot and is now bumpier. Now we have to just look at the data and work on that."