Fujiwara finished in second place behind Kenya's Michael Kipyego (R) at the Tokyo Marathon in February [Reuters]

The hip-shaking Japanese fitness fad of curvy dancing helped marathon runner Arata Fujiwara to qualify for the London Olympics.

Hiromi Kashiki, the creator of the popular dance style based on hip-gyrating movements, says Fujiwara, who visited her studio for a one-on-one workout the day before last month's Tokyo Marathon, is a natural.

"When I first saw Fujiwara, I noticed his pelvis was going up and down, left and right - it wasn't very stable," she said in her Tokyo dance studio.

"I tried to make sure his pelvic area was more relaxed - removing wasted energy to release that explosive power."

Fujiwara said: "Up till now I've been really bad at using my hips effectively. After I got some lessons from Kashiki and her curvy dancing my running style dramatically improved."

The 30-year-old Fujiwara qualified for the Japan team by finishing runner-up in Tokyo with a personal best of two hours, seven minutes, 48 seconds.

Qualification was a personal triumph for Fujiwara, who quit a marathon squad bankrolled by Japan Rail to go solo two years ago.

He relied on donated shoes and trained in a Tokyo park.

"I don't have any cash but people have helped me out in all sorts of ways, so I've been able to get by," he said under the plum blossoms in the park.

"It was a real struggle. (Ernest) Hemingway says in one of his short stories ('A Moveable Feast'): 'Hunger was a good
discipline'. Well it's exactly like that.

"Being starving, being hungry, really was character-building."

Fujiwara will be joined in London by Ryo Yamamoto, 27, and Kentaro Nakamoto, 29.

The Olympics begin on July 27 with the men's marathon on August 12.