Matt Damon reveals physical challenge ‘The Odyssey' cast faced

Matt Damon has revealed that the greatest physical challenge of filming The Odyssey was not the sword fights or sea battles, it was the footwear.

Speaking on Radio Andy with host Andy Cohen, the 55-year-old actor confirmed that all the action sequences were filmed with the cast in sandals, which led to some very unglamorous consequences for a group of largely middle-aged performers running across ancient stone sets.

"A lot of us are middle-aged people and what we got was back pain because, oh my god, running through Troy, it's all stone," Damon said.

"You're in these sandals, and they're very real. Our feet were all scuffed up, but more than the little scratches and cuts on your feet, it was the back pain for us. It was a heavy Advil movie in those weeks when we were doing that action stuff."

Damon did not arrive on set unprepared, however. 

To play the legendary warrior king Odysseus in Christopher Nolan's nearly three-hour adaptation of Homer's epic, he carved himself down to 167 pounds of muscle, a process he described to PEOPLE as "a whole lifestyle change."

During the film's global press tour he also appeared on The Tonight Show Starring Jimmy Fallon, where he shared a colourful behind-the-scenes moment involving co-star Tom Holland, who plays his onscreen son Telemachus. 

Holland's costume apparently ended up "choking" him at one point, and Damon mistook his co-star's attempt to address the wardrobe malfunction as an acting choice.

The Odyssey, which also stars Anne Hathaway as Penelope, Queen of Ithaca, is in cinemas now.