As cross-country skiers and biathletes prepare for the upcoming 2022 Beijing Winter Paralympics in Baiyin, Gansu province, a team works every night to keep the trails maintained.

"After a day of training, there might be damage to the runs. We need to repair them with artificial snow," said Wang Xinglong, a trail maintenance worker at the national winter sports training base in Baiyin.

Temperatures in the area hover around 10 C during the day and can drop to around-15 C at night.

Despite the low temperatures, Wang and his colleagues start work after midnight.

"When the temperature is lower, the quality of artificial snow we make is more suitable for skiing," he said.

Over the past two months, the team has been doing this special "cosmetic surgery" on the trail every night. The machine normally starts to make snow as soon as it is connected to power and water, but on this occasion, the main pipe was frozen solid.

Wang picked up a heating lamp and warmed the pipe carefully.

"It can be defrosted in 10 minutes," he said.

In addition to the low temperature, variable winds were another difficulty.

"We are really wary of changes to wind direction. If it suddenly starts blowing in the direction the snow is coming out, the snow might get blown into the machine and cause damage," Wang said.

Each time that happened, the machine was stopped, turned in a different direction and restarted.

After the team spent several hours battling the fierce winds and the freezing cold, the night's snowmaking was done and trail patrol began.

Lu Wen, a manager at the base, got on a snowmobile and made his way slowly along the 3.5-kilometer-long trail to check if the snow was thick and wide enough.

"The run should be at least 8 meters wide and about half a meter thick," he said.

At 4:30 am, returning after about an hour of patrolling, Lu was as cold as a popsicle. "It's really freezing, but I've become used to it," he said.

With the newly laid snow meeting requirements, Wang boarded a grooming machine to tidy up the trail.

He usually drives the course four times, which takes about three hours. "If we do this too early, the snow can become hard. We usually finish work around 7:30 am in order to provide the best conditions for our athletes, who start training at 9 am," Wang said.

Many workers at the base, including Wang and Lu, were nearby farmers.

Since the end of 2019, when the base became operational, they have grown into a team of professionals.

During the Spring Festival, as athletes trained as usual, Wang and his colleagues also chose to spend the holiday at the base.

"Winter sports have changed our lives. We are all proud to make a contribution to support the training of our athletes for the Paralympic Games being held in our country," he said.