Harry Hill, president of TV shopping channel operator Oak Lawn Marketing Inc., received a lot of discouraging comments from Japanese when he thought about selling the "Billy's Boot Camp" exercise DVDs.

"People say, 'We Japanese don't do that.' It's amazing. Does everybody in Japan think the same?" Hill, 46, a resident of Nagoya, said near the company's Tokyo office in Minato Ward. "I'm an entrepreneur who sees opportunity which others see as problems," he said. "The worst that could happen is I fail."

That DVD alone earned ¥20 billion for Oak Lawn Marketing in 2007 and many kinds of physical exercise DVDs have since been put on sale as other companies hoped to take a slice of the market pioneered by "Billy's Boot Camp."