The beds in the Olympic Village went viral leading up to the Games ... with many believing airweave's design was meant to prevent athletes from getting freaky.

But, the big question -- how on earth the things could actually supply enough comfort for world-class athletes??

So, when Eaton returned from Tokyo on Tuesday, we had to ask about 'em ... and he played it straight!!

"Ugh, those cardboard beds were tough!!" Eaton told us at LAX.

"The funny thing, want to know something funny, I didn’t complain about it once because I knew if I complained about it, I would not get sleep."

But, Eaton came up with a solution -- he tells us he would purposely tire himself out all day ... so when it was time for bed, he'd be out like a light!!

"I ended up just taking my days really long and making them exhausting so I could just sleep."

It definitely worked out for the 20-year-old pro skater -- he ended up winning the bronze medal, the first Olympic skateboard medal for the US!!!

Eaton told us all about his Olympic experience ... saying it was a "friendly battle."

"I feel like I thrive on skating with my friends, that’s what I was doing," Eaton said.

"I was skating with my buddies and I know we’re all going head-to-head, but that’s also why I love these boys and they’re my friends because they want to win too."

Eaton also gave us a glimpse of his shiny Olympic medal and told us he doesn't have his own place yet, "so it’s gonna go to my mom."