Seven-time Tour de France champion and cancer survivor Lance Armstrong is enjoying a working vacation on the Big Isle in preparation for his return to elite road racing.

Armstrong, 37, has been cruising the highways and country roads of Kona and Kohala on his bicycle since arriving Sunday, documenting his adventures with brief postings on the online social networking service Twitter.

Yesterday's reports included a notation that Armstrong "hammered 80 miles today. Last hour on TT (time trial) bike. Hot and sunny here today."

A second Twitter entry filed the same day said, "Happy NYE to you all. Queen K and I spending some time together today" — an apparent reference to Queen Ka'ahumanu Highway, which cuts through the lava fields of South Kohala.

The cycling legend also shared a photo taken with his wireless phone of Sacred Heart Church, with the comment: "I love this little church in Hawi."

Vernon Sekafetz, manager of Bike Works Kona, which rents and sells bicycles, said there's been a little bit of a buzz about Armstrong training on the Big Island and a few sightings. He said folks along the sunny Kona and Kohala coasts are used to having celebrities in their midst.

"It doesn't faze me at all to hear that he's here. But if he walked in here it would be a different story," he said.

In September, Armstrong, who lives in Austin, Texas, announced he was emerging from three years of retirement to race in the 2009 Tour de France. His first comeback race will be the six-stage Tour Down Under that starts Jan. 20 in Australia.

In between his training runs on the Big Island, Armstrong has been able to find time for golf and playing with his children, according to his posts.

His first entry on Sunday said, "Just made it to Hawaii. Long trip! Looking fwd to some good training before the Tour Down Under."

Armstrong's coach, Chris Carmichael, told the Australian sports Web site http://wwos.com.au, "We're going out (to Hawai'i) so Lance can continue putting in the miles, and I'm considering putting him behind the motor for some motorpacing as well."

Carmichael told http://wwos.com.au that Armstrong was "ahead of schedule" in terms of his training but that fans shouldn't expect too much from him at the Tour Down Under.

On the Big Island, he went cycling with a friend the day he arrived, noting: "Beautiful weather. Kids are in heaven."

In other entries, Armstrong mentioned playing six holes of golf: "Perfect amount of golf ... Tiger doesn't need to worry."

The next two days were spent in more serious training. Monday's Twitter post said, "5 hard hours today. Up to Hawi then climbed over to Waimea then home. Some serious wind here."

On Tuesday, Armstrong tackled the Kaloko Road switchbacks in North Kona that climb to a fern and 'ohi'a cloud forest at the 5,000-foot elevation.

At 10:07 a.m., he reported "climbing Kaloko." An hour and 16 minutes later came another post: "Top of Kaloko! ... Steep, steep, steep."

Armstrong also visited the Big Island in February, when he paddled an outrigger canoe and had a close encounter with a humpback whale, according to his Lance Armstrong Foundation blog. He launched his nonprofit foundation in 1997 to support people with cancer, raise awareness about the disease and fund research. For more details, visit www.livestrong.org.