The Running in the Dark charity was established in 2016, aiming to improve the well-being of people with disabilities, and generally help them get out of the house more by building a social outlet for them.

The Beijing branch of the group was founded in 2019, and it now caters to more than 400 runners, including those with hearing impairments and cerebral palsy.

Over 600 volunteers have signed up to become running guides, fitness coaches or help with logistics.

Among them is Hou Yong, who is known as "Brother Tiger" in the running group. Being a regular marathon runner himself, Hou coaches and guides the group members.

"I started to run marathons in 2015, and later I started to help visually impaired runners in some events. I just thought it would be nice to help others while running," Hou told China Daily.

"Initially, it took a while to get used to as we were bumping into each other and our speeds were different. And honestly speaking, I was quite nervous, as I didn't know what to expect.

"Gradually, I learned from the experienced guides, and now I can offer the runners better assistance.

"Once you truly get to know the runners, you can have great communication with them. And you can be great friends with them."

He Xiaoyun, the leader and founder of the Beijing branch of Running in the Dark, says the guides and volunteers need to adapt to the requirements of each disability.

"We have constant training, not only for the runners with disabilities, but also for the guides and volunteers. For visually impaired and hearing-impaired runners, we need to offer different assistance," He told China Daily.

"Also we need to pay special attention to their psychological needs. We need to let the guides and volunteers know how to appropriately help the runners.

"We are not simply a group for people with disabilities to exercise — more importantly, we are a platform for them to integrate more in society and generally socialize more."