MMA legend Conor McGregor may have already announced his retirement from professional fighting but he's still open to exploring other sports. On Monday, he was spotted racing water bikes with Princess Charlene of Monaco.

The unusual pair was seen zooming through the water off the coast of Monte Carlo. According to The Sun, the "Notorious" and the ex-Olympian are planning an epic 180 km voyage in September.

Princess Charlene is a former Olympic swimmer and was a prolific athlete before capturing the heart of Monaco's Prince Albert II. She will be joining McGregor in a charitable event wherein they plan to travel via water bike from Corsica to Monaco. The event is an initiative by the Princess Charlene Foundation, which aims to raise awareness about water safety.

Princess Charlene and the former UFC champion were both joined by their significant others. Prince Albert II of Monaco and Dee Devlin were seen supporting the two athletes as they spent time preparing for the upcoming event. All four of them posed for a photo together, which McGregor shared on his Instagram.

"A great day racing the water bikes with Princess Charlene of Monaco. A phenomenal athlete and Olympian, we are teaming up for a 180 km voyage in September to raise awareness in water safety.
I cannot wait!," said McGregor.

With such a long voyage planned, even healthy athletes need ample training and preparation. "We will be utilising my training under the McGregor F.A.S.T program to excel on these mounted water bike devices, which are incredibly good!," he added in the same Instagram post.

Princess Charlene, who is now 42 years old, represented South Africa as a swimmer at the 1998 and 2002 Commonwealth Games. She also participated in the 2000 Sydney Olympics. Meanwhile, McGregor is a former UFC featherweight and lightweight champion.

Back in June, McGregor made the surprise announcement that he will be retiring from professional MMA. This isn't his first so-called retirement and many of his fans are still hoping to see him back in the Octagon. It remains to be seen if he will have a thirst for fighting again. In the meantime, he is clearly into water bikes.

Conor McGregor
Conor McGregor PAUL FAITH/AFP/Getty Images