Martin Strel. Photograph: Robert Ghement/EPALater today, Martin Strel will be going for a swim. So far, so normal. But this one will - hopefully - last 70 days and take him 3,375 miles.
The 52-year-old Slovenian, the self-professed king of marathon swimming, aims to cover the entire length of the Amazon.
He has form. Starting in 2000, he swum the 1,867-mile length of the Danube before building up to the Mississippi two years later and then, in 2004, the 2,488 miles of the Yangtze.
As his official expedition website explains, this adventure is more dangerous than any of the others, partly because of unpredictable currents and floating debris, but also due to the various creatures that lurk in the Amazon's waters.
These range from the merely terrifying, such as piranhas, bull sharks and stingrays, to the downright blood-curdling candiru, or toothpick fish, that can swim into a tiny body orifice - the penis is a favourite - erect a spine and feed on blood and tissue.
In an interview, Mr Strel explained how his support team would keep him safe - lots of blood:
My escort boats will carry all the time buckets of fresh blood to pour in the water in case the piranhas or other fish attack me.
A professional marathon swimmer since 1978, Mr Strel has higher aims than what his at times less-than-modest personal website describes as his "great sports achievements".
He aims to raise awareness of "universal messages", and stages his adventures under the eminently sensible slogan of "swimming for peace, friendship and clean waters".
As a job, it is not for everyone. But then, Mr Strel's background prepared him well for it, as he explains on his website:
As a young boy, I was beaten a lot by my parents and schoolmasters. This no doubt contributed greatly to my ability to ignore pain, and [to] endure.
