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Finland has seen particularly heavy snowfall this winter and running outside in just socks provides great exercise as well as a sense of freedom, said Pekka Parviainen, a helicopter pilot and an avid barefoot runner.
"This is traditional Finnish crazy stuff, I think we all agree," said Parviainen while out running with a group in Nuuksio national park, 35km from the capital Helsinki.
"And it's really the happiness side. I mean it's very good sport, strong exercise and everything, but it really is the happiness," he added.
In Finland, where taking a sauna in winter and then running through snow to jump into an ice-cold lake is a traditional pastime, barefoot running has become popular in the past few years during the warmer months.
Running in socks through heavy snow - now about half a metre deep in many places - takes this to the next level.
"You can do it quite light or you can do it really heavy in the deep snow as we did now. But the feeling afterwards is just great. You have had a good foot massage," Parviainen said, because your feet are not tightly "packaged" in trainers.
There is no shortage of warm woollen socks as many Finns have taken to knitting during long winter lockdowns.
Parviainen recommends wearing at least two, preferably three, pairs of woollen socks to get the most out of the run.