Nick Jonas is one hot man, but he's also super cool -- and by cool, we mean like freezing!

The pop star stripped down to nothing but his skivvies to cross a freezing-cold lake while on Running Wild With Bear Grylls. The “Jealous” singer ditched his clothes to cross an icy lake in the Sierra Nevada Mountains on the show’s season 3 premiere.

The former Jo Bro risked cardiac arrest and losing circulation in his hands and feet to plunge into the freezing lake with nothing more than black Calvins. The sexy star pushed his waterproof back back in front of him to get across the lake.

Swimming across the lake, Nick gives himself a pep talk, saying, "We can do this. We got this."

Nick is a diabetic and seemed to have trouble getting his circulation back after his chilly dip, and needed Grylls to help warm him.

After surviving, Nick said, “It’s crazy what happens to your body, the instincts that kick in. You just have to go, push yourself.”

Running Wild With Bear Grylls will then return to NBC following the network’s Olympic coverage with guest star Courteney Cox in Ireland on August 22 at 10 p.m. ET.