In a Tehran park, a group of young women brave sneering men and shocked looks as they perform flips, mid-air somersaults and bound from pillar to pillar in a surprising sight in a conservative Islamic country.
The group has discovered parkour, the fast-moving sport blending acrobatics and gymnastics that has become their outlet for evading social constraints and dealing with stress.
"As a woman, it's a bit complicated," concedes their teacher Maryam Sedighian Rad, a 28-year-old who holds a masters in physiology.
She and the others wear the "hijab" obligatory in Iran, which requires women to cover their hair and much of their body in loose clothing to prevent their figures being seen, and her group often has a male escort when they practise outside to ward off unwelcome company -- and sometimes police.
Born in France in the late 1980s, parkour involves getting around or over urban obstacles, with a fast-paced mix of running, jumping, and gymnastic rolls and vaults.
Offering a cocktail of excitement, danger and risk, it caught on around the world thanks to blockbuster movies like "Yamakasi" and "District B13".
Now, it has gained a foothold in Iran -- and not only among the usual young male aficionado.
Sedighian Rad and some 50 women -- teenagers and young adults -- are among the hundreds of Iranians practising this non-competitive discipline that morphed from military obstacle course training into a mainly urban sport.
The parkour motto, "Never move backwards," seems to hold particular resonance here.
Three times a week, Sedighian Rad trains her groups at three indoor sports complexes.
"We encounter problems but we try our best to cope with them because we love doing parkour," says Sedighian Rad.
While their baggy outfits allow for ease of movement, the jogging, jumping and somersaulting can cause hair to fall loose.
Unperturbed, Helia Goharbavar, 16, readjusts her hijab after every move.
"It doesn't bother me," she said. "It's cold anyway and you have to wear something. Besides, we are used to it."
- 'I feel free' -
One of the most agile in the group, 17-year-old Arefeh Shoari, admits she often fears that certain moves might expose parts of her body.
But she and the other girls say parkour -- often billed as a holistic discipline -- has given them freedom and confidence.
"There was a jump I couldn't do at first ... learning it made me realise I am capable of doing anything and defeating any obstacle," says Sedighian Rad. "I feel free."
Shoari says parkour allows her to cope with everyday life.
"I am really stressed out because of my studies but parkour helps me a lot to deal with the stress," she says. "I feel happy."
"Practising parkour shows that even if you are a woman, you are not bound to stay at home," says Goharbavar.
Apart from the risk of injury in this hard-knock sport, the women also brave derision in a country where mixed activities are banned.
"Sometimes people criticise us saying this isn't a sport for girls. They say we're supposed to knit … They can't imagine a girl exercising like a boy," Sedighian Rad says.
Athena Karami, 19, recalls how she once had to leave the park during practice after a crowd of teenage boys "made fun of us and filmed us with their mobile phones".
To head off such problems, Sedighian Rad usually takes along male members of "Hitall" -- the parkour club she joined in May 2012 -- when her group trains outside.
At times police have interrupted their workout.
"But when they see that it's just a sport and that we are really exercising, they let us be," Sedighian Rad says.
"Sometimes they even express interest in parkour and ask where they can get training."
[Image via Agence France-Presse]