Lance Armstrong showed he had the "spirit of a fighter" after he left many of his young rivals trailing behind during the gruelling 199.5km 16th stage of the Tour de France on Tuesday.

The 38-year-old, competing for the last time at the Tour where he won a record seven titles, attacked almost from the gun as he climbed the passes of Peyresourde, Aspin, Tourmalet and Aubisque before finishing sixth.

With his locket swinging around his bare chest as he gasped for air during the punishing ascents, Armstrong led the way for most of the day but was overtaken as he closed in on the finishing line.

"I'm alive, I trained hard. I'm not the best guy in the race but still have the spirit of a fighter," Armstrong said as sweat dripped down his neck.

Yellow jersey holder Alberto Contador, Armstrong's fierce rival last year, said he would have liked his former teammate to win the stage.

"It reminded me the 'old' Armstrong and I would have been pleased if he had won," the defending champion said.

The American, however, took the time to soak up the support of the thousands of fans lining the French roads.

"They don't have to come to the Tour, they don't have to fly from all over the world and stand on a hot roadside, but they do and I appreciate it," said Armstrong, who was cheered along the way.

"This entire Tour the fans have been really nice to me and very supportive and today we're out there ... it's a small group, so they can be close to you, touch you."

With the end of his career in sight, Armstrong was already looking forward to spending some days at the beach with his family.

"Lance Armstrong is over in about four or five days," he said.

Pierrick Fedrigo of the Bbox-Bouygues team held off the threat of Armstrong to hand the host its sixth success on Tuesday.

Astana's race leader Contador, who took the yellow jersey from Luxembourg rival Andy Schleck on Monday, came over the finish line just under seven minutes later.

Schleck, who lost the yellow jersey to Contador after suffering a mechanical problem on Monday's 15th stage, was expected to take his revenge but failed to make up any ground.