So cold — yet sooo hot! Nick Jonas stripped down to just his boxer briefs to cross a freezing-cold lake during his appearance on Running Wild With Bear Grylls on Monday, August 1. The “Touch” singer impressively ditched his clothing in the season 3 premiere to cross an icy lake with the wild man in the Sierra Nevada Mountains.

Risking cardiac arrest and losing circulation in his hands and feet, the “Bacon” singer, 23, plunged into the freezing water in just a pair of black Calvin Kleins while pushing his waterproof pack ahead of him. The pair had to get into the lake to get across.

“We can do this,” a red-faced Jonas can be heard repeatedly telling himself as he swims across the lake. “We got this.”

“My toes are freezing,” Jonas said after surviving the task. “It’s crazy what happens to your body, the instincts that kick in. You just have to go, push yourself.”

Jonas, who is diabetic, had trouble getting his circulation back and leaned on Grylls to help warm him back up.

The former boybander also had to survive off bird guts. “Nick Jonas never misses an opportunity,” one viewer tweeted at the artist Monday night. “Never,” he responded. 

Running Wild With Bear Grylls returns following NBC’s Olympic coverage with guest star Courteney Cox in Ireland on August 22 at 10 p.m. ET.

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