Most popular trainer

During each 90-minute livestream, most of them starting at 7:30 pm, people chat while dancing together to songs, type friends' names on the screen to check their attendance and offer encouragement to each other.

In between the four-minute songs, Liu and his wife, Wang Wanfei, talk to followers for several minutes to let them take a breather. Liu also demonstrates the movements and reminds the attendees to avoid incorrect postures, which could lead to injuries.

"Your heart rate remains at 120 to 150 beats per minute, which is good for losing weight and toning the body," he said.

"I'm happy to see so many people that never took exercise before have now started working out with my livestream because that means they have taken a step toward a healthier lifestyle."

However, as there are many new starters, Liu said livestream coaching needs to favor the majority and trainers should avoid movements that are too complex.

"I haven't yet led people in livestream exercises where they support themselves with their hands on the floor, because new starters might get injured if they do it incorrectly," he said.

He has been a fitness fanatic for more than 30 years, and has published several books, including A Fitness Book by Keng-hung in 2004, and Fitness Can Change Your Life in 2014.

The first book became popular because Liu was a star actor who had helped his celebrity friends share his fitness experience.

"I wanted to let people know that no matter how busy you are, you have time to work out," he said.

"In the book that was published eight years ago, I wanted to tell people that 'fitness can change your life', even though the publisher said the idea was too advanced and might be hard for people to understand.

"Fitness is not only about losing weight and building muscle－it's a lifestyle that makes you healthier, happier, have a great career and benefits your relationships with family and friends."

He said his current popularity is not something he achieved in several months. Instead, it's the result of many years of work.

"From introducing my family and friends to my fitness regime, to becoming an instructor on TV shows and making coaching videos and livestreams, I have been doing this enthusiastically," he said.