WARSAW (AFP) - A Polish gym has dubbed itself a church in a bid to stay open under new anti-virus restrictions that have seen the fitness industry scramble for creative loopholes.

"Because fitness classes aren't allowed, starting today we're offering religious gatherings for members of the Church of the Healthy Body," the Atlantic Sports club said on Facebook.

"Hard to believe? In this world everything is possible," the gym in the southern city of Krakow added Saturday.

Atlantic Sports also declared it was opening a store with exercise equipment and welcomed everyone to head on over and test it out for a fee.

The creative rebranding follows the government's decision to shut down most pools and gyms in order to stem a recent surge in coronavirus infections.

Measures introduced this weekend also require restaurants to close early nationwide, while weddings are banned and secondary schools have switched to distance learning in Warsaw and other high-risk red zones.

But church services are still allowed to go ahead in the devout Catholic country of 38 million people, as long as the faithful wear masks and abide by the attendance limit.

Many Poles have taken to social media to share satirical takes on the different rules for churches and gyms, some juxtaposing images of buff gym-goers - the "at-risk group" - and "immune" parishioners.

In Warsaw on Saturday, a couple hundred people braved the rain to attend a fitness industry rally against the restrictions, some holding up signs with slogans such as "physical activity = immunity".