Moscow, Red Square, the historic heart of the Russian capital.

As on most days, tourists are milling around, taking pictures of the Kremlin and St Basil's Cathedral.

Suddenly, a commotion erupts on one side of the square.

Camrophones swivel away from the famous landmarks

towards an astonishing, unexpected sight. A group of nine children barely in their teens are swiftly

moving across the cobblestones in the line. Their faces are partially covered by animal masks.

Some are foxes, others are cats. Several have bushy fake tails trailing behind them.

But even more striking than what they're wearing is what they're doing. Instead of running on two

legs, they're bent over, scampering along on all fours. The scene I'm describing is from a TikTok

video, part of a youth craze which has taken Russia by storm.

Quadrobics is a form of exercise which involves walking on all fours, using your hands as your front legs.

But quadrobers, as enthusiasts are known, don't just copy the way animals move, they also dress up a bit like them.

However, the explosion in the popularity of quadrobics has also sparked a moral panic.

Religious leaders have condemned quadrobics as dehumanising,

and senior politicians claim it's undermining Russian values.

They've even threatened a law to ban its promotion.

Those who make this movement popular and attractive must be punished.

Not surprisingly, quadrobers are feeling under attack.

Perhaps a hobby is unconventional, but this is not the reason to accuse us of all sorts of

stupidity and fight us.

Welcome to the documentary from the BBC World Service.

I'm Ed Main from BBC Trending,

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