On a chilly Sunday morning, over 35,000 athletes from all corners of Fuzhou swarmed to the city's exposition center, limbering up for a marathon race with stirring music that blared from loudspeakers at the starting line.

When the gun was fired at 7:30, racers wiggled their way out of the crowd, running toward the finish line of the world's first IAAF Gold Label road race in the new year as one of the most primitive sports continues to blossom in China.

After much sweating and stress, Li Jingyi, a 30-year-old Xiamen local, accomplished the first full marathon of her life at this year's Xiamen Marathon.

Li is one of the many fueling the boom of long-distance running in China. Due to fast economic growth and a growing middle-income population that is more keen on staying healthy, China has seen an exponential growth of road races in recent years.

According to the Chinese Athletics Association (CAA), while China only hosted 22 running events nationwide in 2011, that number soared to 1,102 in 2017.

But the uptrend is slowing down. By the end of November 2018, 1,072 marathon and road running races have been held in China. The number is estimated to reach 1,300 for the whole year.

Shui Tao, director of the marathon branch of CAA, said it is natural that the torrid growth would smooth out at some point, just like China's economy.

"Last year saw the tipping point of China's marathon development, which is switching from a high-speed boom toward a trajectory of viable and quality development," said Wang Nan, vice-president of the CAA.

The association vowed to put in more efforts to keep running races clean after a flurry of scandals at marathons that cropped up with their rising popularity, such as cheating by runners and unprofessional behavior by organizers.

The booming industry, which has lured many companies for business opportunities, now looks to be transitioning from rapid growth to high-quality development.

The Xiamen Marathon, which received 77,000 racers at its highest mark, only offered 35,000 spots this year. This is because instead of trying to attract more participants, the organizer is now focusing on "better services" for racers.

Many cities and private enterprises flooded into the sector because they believe the races can expand the influence of local tourism and prop up economic growth. But among the many events held in China, only a few have make money thus far.

"The industry will go through a 'reshuffle' as the fever subsides," said Tao Tingting, president of sports event organizer Chang'ao Sports.

Tao, who also owns an e-sport team, invited top e-sports gamers to run races and play games with fans after the race. The trick attracted thousands of young gamers during every event.

The Chongqing Marathon, another IAAF Gold Label road race, offers 100 hotpot dinners to 1,000 racers selected via a lucky straw, earning it the name of "hotpot marathon."

Though venture capital injection into the industry has dwindled to a mere trickle, investors now eye technological innovation as the new driving force for the industry.

Ding Duo, an angel investor in sports and health, said a game changer in the upcoming 5G era would be a new technology, able to reshape the way racing events are organized and operated.

Alisports, the sports arm of e-commerce giant Alibaba, rolled out a "digital marathon," hoping to uplift running events by using its ubiquitous big data collecting and computing capacities.

Yang Yong, general manager of the race division of Alisports, said that by using facial recognition, 11 racers were found running with forged bibs or cheating during last year's Hangzhou Marathon.

"We are also encouraging racers to get more involved in the event and the city," Yang said. "For example, by playing a game that combined online and offline scenarios, racers received a virtual gift box of coupons at each tourist spot they visited."