From halfway up Lotus Hill, people can hear loud laughter coming from the top every Monday, Wednesday and Friday evenings between 8 p.m. and 8:30 p.m. Once up there, several hundred people laugh together, as they jump, pat each other's hands, and make funny movements. All two dozen movements end in hearty laughter.

These are not behavioral artists. Red T-shirts printed with a big smile on the front and Chinese characters on the back give away their identities as members of Shenzhen's Laughter Club, which was started last March by resident Zhang Lixin.

Zhang, originally from Jinan, capital of East China's Shandong Province, had been running a foreign trade firm in Shenzhen for 12 years before he gave it up completely and put all his time into the "laughter career."

"I became very unhappy after years of running a business. Under a lot of stress, I often quarreled with my wife and I didn't feel satisfied. I worked out in gyms, went hiking, and spent nights at pubs, but I soon felt bored again," the middle-aged man said.

Zhang noticed a piece of news about laughter yoga late last year and became interested in the idea. He contacted Chen Dacheng, who runs such clubs in Taiwan. Chen introduced him to Madan Kataria, the Indian founder of laughter yoga.

Zhang first practiced laughing with his wife behind closed doors at home during this year's Spring Festival. "We did it in secret, afraid of being heard by neighbors. Soon I felt the practice improved my health and mood, and considered promoting it among the public."

He launched a Web site www.axcctv.com, printed more than 10,000 copies of pamphlets to teach people about laughter yoga, and gave the first public demonstration at Lotus Hill Park on March 19.

"I am still grateful to the first five schoolgirls who joined me laughing that Sunday morning. I almost lost my courage but it got easier as more people joined us," he said.

Apart from three evenings a week, several hundred people now regularly come to laugh with Zhang by the lake in Lotus Hill every morning starting at 7:45.

Most elderly people do it for health, as research has revealed that the process of laughing helps the human body produce endorphins which speed up blood circulation.

There are also young people in the club, who have found it a good way to release stress.

"My job requires me to face the computer all day long. I seldom talk to people, except on the Net. As a result, I 'laugh' most of the time just with a symbol on the screen," said Xu Shan from a computer software company in Nanshan District. "It felt a bit unnatural to laugh out loud at the laughing session at first, but I soon forgot about it. It feels so good to laugh without reason, it even cured my insomnia."

Zhang also travels every Saturday morning to Guangzhou and organizes a laughter session on the Baiyun Mountain.

"I do it for free now. But I believe it will become a profitable business later on, if I can find advertisers to sponsor such events," he said.

He also mentioned that a Guangzhou magazine is helping him release a laughter yoga DVD and he is writing a book on the topic.

There are some 5,000 laughter clubs worldwide, most of them in Europe. The "World Laughter Day," proposed by Madan Kataria, an Indian family physician, was first held in 1998, and is now celebrated on the first Sunday in May every year.

Editor: Donald