AceShowbiz - Actor Josh Brolin's attempt at new wellness trend - "perineum sunning" - delivered disastrous results, as he was left with a burnt "pucker hole."

The "No Country for Old Men" actor revealed the effect of attempting to tan his bottom in a candid Instagram post, as he confessed to having to cancel a Black Friday, November 29 shopping trip because he was "using aloe and burn creams because of the severity of the pain."

Alongside a photo of a naked man lying on his back with his legs in the air as the sun kisses his posterior, he penned, "I don't know who the f**k thought of this stupid s**t but f**k you nonetheless. Seriously."

The idea of "perineum sunning" soared in popularity last month, when Instagram health influencer Ra of Earth posted a now-viral video of three naked men lying on the grass with their legs up, exposing their bottoms to the sun.

"In a mere 30 seconds of sunlight on your butthole, you will receive more energy from this electric node than you would in an entire day being outside with your clothes on," they explained in the clip.