HELSINKI — Sporting a black leather jacket, dyed red hair and a tattooed arm, Alisa Aarniomaki looks like she’s on her way to a rock band rehearsal session.

But instead of carrying a guitar, the 20-year-old Finn gently holds on to something else: a puffy stuffed horse head on a wooden stick complete with glued-on eyes, mane and reins.

She’s been riding real horses from the age of 10 but became instantly smitten by hobby-horsing – a sport with gymnastic elements that has spawned a social media subculture among Finnish teen girls – when she first heard about it on a web discussion forum several years ago.

“Hobby-horsing has a strong therapeutic side to it,” says Aarniomaki, adding that it has helped her to deal with difficult personal issues such as her parents’ divorce and bullying at school.

“I’ve gone through lots of trouble and I’m still struggling with some issues. It has helped me a great deal that I can occasionally just go galloping into the woods with my friends. It somehow balances my mind.”

Like a real horse and its rider, the hobbyhorse and its master form a team and become attached to each other. Similarly, the sports simulates traditional equestrian events including competing in dressage and show jumping, and is physically demanding.

Hobby-horsing has gained momentum outside Finland because of this year’s release of the documentary “Hobbyhorse Revolution” by the Finnish Oscar-nominated director Selma Vilhunen. Over a year, she followed young hobbyhorse enthusiasts and their preparations for a competition.

Some actual horse riders may look down on hobby-horsing as childlike past-time not suitable for anyone older than 10, but Fred Sundwall, the secretary general of the Equestrian Federation of Finland, disagrees.

“We think it’s simply wonderful that hobby-horsing has become a phenomenon and so popular,” Sundwall said.