Li Min, a sport enthusiast who used to practice yoga, hip-hop and taekwondo, has turned into a fervent fan of Heyrobics.

"It requires no basics, everybody dances with the music. Each session is designed to comply with how the human body works and it totally frees me from any pressure," Li says. "My colleagues always says I am now more energetic even when I work extra hours."

Holmsater leads a rooftop workout at the Bookworm in Beijing.

She also highlights the special charm of Heyrobics classes, in that they always serve as occasions for cultural exchange and making friends.

With more than 60 variations in Sweden, Heyrobics is an exercise for all age groups — each person can find an exercise to suit them. With the "hey" frenzy growing, the team is introducing more variations into China.

There are now eight versions in Beijing, and bar workouts were introduced recently, scheduled once a month in a bar, with DJ playing popular beats and Heyrobics instructors leading the exercises.

Holmsater also plans to start Heyrobics in Shanghai in September, and then on to more cities in the west and south.

"My ambition is to make Heyrobics easy for everyone to start no matter if he is in big cities or a small city of 5,000 people," Holmsater says.