Former Chelsea star and World Cup winner Andre Schurrle took on the Iceman Challenge, meaning he walked up a mountain while topless in below freezing temperatures.
Schurrle enjoyed a glittering career that saw him win the Premier League with Chelsea and assist Mario Gotze's winning goal in the 2014 World Cup final.
However, he retired at the end of 2020 aged 29, with the former German international revealing he no longer wanted to have to deal with the loneliness and endless competition inherent in top-flight football.
Since retirment, Schurrle decided to take himself away from the game and enjoy time with his family.
But on Sunday, he shared a post on Instagram revealing he had undertaken the Iceman Challenge, inspired by Dutch extreme athlete and motivational speaker Wim Hof.
The challenge consisted of Schurrle having to trek up a snow-covered mountain without wearing a T-Shirt, in what is meant to be a severe test of participants' mental and physical strength.
The German wore only shorts, gloves and hiking boots in below freezing temperatures during his expedition.
In his post, the former German forward said: 'Day three of the Wim Hof Experience and up the summit with our beautiful crew!
'The hardest mental and physical thing I ever did! The last minutes I couldn’t feel anything and I had to find something deep inside me to keep going.
'An experience that I will never forget. Minus 19 degrees centigrade, 100 km/h wind in our faces, heavy snow and rain. What I learned: my body and I are stronger than I thought. If I put my mind and soul to it I can do everything.'
Schurrle was clearly delighted with the experience he had undertaken and received plenty of support for his post.
This included his former Chelsea team-mate Didier Drogba who commented: 'Fashion week @AndreSchuerrle proud of you my man my body would have stopped functioning straight away.'
Schurrle ended his career having scored 86 goals in 373 appearances which included spells with Mainz 05, Bayer Leverkusen, Chelsea, Wolfsburg, Borussia Dortmund, Fulham and Spartak Moscow.
Meanwhile, his international career ended in 2017, with the forward having netted an impressive 22 times in 57 games.