Armstrong back on his bike

Two days after a crash forced him out of the Tour of California with a bruised elbow and a cut below his left eye, Lance Armstrong was back on his bike on Saturday, the seven-time Tour de France champ tweeted.

"First ride after the face plant," Armstrong said on his Twitter feed, adding that he rode for one and a half hours "easy" and "got passed by a lot of people".

With a month and a half to go until the Tour de France, RadioShack team manager Johan Bruyneel said Armstrong's injuries - he required eight stitches in the cut on his face - were a "setback", but they wouldn't compromise Armstrong's start in the Tour de France or his preparations.

Armstrong crashed on Thursday shortly after the start of stage five outside Visalia, California.

Prior to the stage he had found himself embroiled in new doping allegations, dismissing accusations levelled by his former teammate Floyd Landis.

The 38-year-old Texan and his RadioShack team were quick to challenge Landis's credibility.

Armstrong had already been forced out of one race this year, pulling out of the Circuit Sarthe in April with an intestinal virus.