Woman swims over 90 miles back-and-forth in swimming pool for two days straight

For 48 hours, Karolina Szczepaniak swum back and forth and back and forth and back and forth between the two ends of the 25 m (82 ft) swimming pool, not getting out, not sleeping, just pausing to eat and drink at the edge of the water before splashing back into her rhythmic laps.

The Polish athlete has a 17 year-long history of exhausting swims, including twice at the Olympic Games, but her recent Guinness World Records attempt truly was a spectacle unlike anything she has tried before.

Karolina was attempting to break the record for farthest distance swimming in 48 hours in a 25 m pool (female), which she claimed with an astonishing 149.02 km (92.59 mi) travelled in just two days.

The spectacular swimmer was inspired to take the title because of her competitive nature and giving spirit. Karolina wanted to prove to herself – and to her community – that she was strong enough to be a record breaker, as she trains for her upcoming August 2025 attempt to swim across the Baltic Sea. 

So she thought she would start smaller by taking a distance record (as you do).

She also wanted to use the opportunity for good by turning it into a fundraising event – her swim was sponsored by a Polish foundation that works on rehabilitation and prosthetics for children who lost their limbs.

“I don't know about you, but in moments of doubt, I go back to the basics of my functioning,” she said on social media. “I say to myself: ‘Hey Karolina, you have hands, you have legs, use them as much as you can, others are not as lucky as you and they don't give up!’

“That's why I can't imagine breaking the barriers of my own psyche and my own body while setting the Guinness World Records title for continuous swimming for 48h, or crossing the Baltic Sea in August, without raising funds for a very worthy cause.” 

But naturally, titles of this nature are very difficult to obtain, so with her priorities in order, Karolina started preparing for the intense swim. 

She did weeks of dieting, sleep training, weight lifting, and swimming to assure she would be fit enough to keep her body moving for so long. A lifelong swimmer, Karolina wasn’t necessarily concerned that she could swim for that long, she just needed to focus on keeping her strength up by timing out her meals and breaks.

And aided by her supportive friends and family and the athletics academy in Warsaw, on 10 February Karolina started her 48 hour swim. Tonnes of fans cheered as she first splashed into the water, and many more would stop by the pool within the next two days as she swam.

Karolina decided not to take any sleep breaks while competing, but she did take short rest breaks, where she refuelled on food and drinks her teammates would pass to her in the water. 

As time went by, you could see Karolina gradually lose her speed – but never her determination – as she moved back and forth between both sides of the pool.

And when the 48 hour timer finally came to a stop on 12 February, a thrilled and exhausted Karolina broke into relieved tears when she found out she took the record.

She celebrated with her proud support system, who showed up in matching shirts to cheer her on:

And she finally had the chance to take care of herself after 48 hours in the pool – by eating snacks (not soaked in chlorine), shaking her pruney hands with excited fans, and taking her measurements – which revealed she somehow only lost 0.2 kg (0.44 lbs) after swimming for 90 miles! 

But the overall vibe in that swimming hall was one of joy and pride, as everyone celebrated Karolina’s incredible accomplishment.

And we can’t wait to see what she gets up to later this year, as she attempts to set the record for longest distance open water swim (female) as she swims from Sweden to Poland across the Baltic Sea this August. 

Good luck Karolina – you’re Officially Amazing!