Bear Grylls on adventuring with President Obama and whether he'd ever host President Trump

As a former British military officer-turned-survivalist, Bear Grylls knows how to take care of himself in the wild. Taking care of other people, though, can be a challenge...particularly when that other person is the President of the United States. In 2015, Grylls was joined by then-POTUS, Barack Obama, for a special episode of his popular reality series, Running Wild with Bear Grylls. The duo hiked through the Alaskan frontier, chatting about climate change and snacking on bear-chewed salmon. Four years later, the 44-year-old TV host still has fond memories of their time together. "Taking President Obama while he was still a sitting president on one of our Running Wild journeys was a definite life privilege," Grylls tells Yahoo Lifestyle, adding that he had to modify part of his pre-show preparation for this particular guest. "Normally I always say, 'Come on your own, no entourage. Trust me, we're going to gun it and go. In this case, they were like, 'Don't say the word gun. And he's not going to be on his own.'" (Watch our video interview above.) Despite some of the conditions placed on their journey--Secret Service snipers were positioned on mountaintops and helicopters tracked their every move--Grylls says that the President was ready and willing to take risks whenever possible. "He was really curious and wanted to learn and was willing to step outside of his comfort zone. I think those are the key elements for progressing in life; otherwise, we get stagnant. He was an amazing guest to travel with." With Running Wild set to premiere its fifth season on National Geographic later this year (the first four seasons aired on NBC), there would seem to be an open slot for another Presidential visit for the current occupant of the Oval Office. "A lot of people say to me, would we do one with President Trump," Grylls says, anticipating our question about whether Trump would ever follow in Obama's footsteps into the wild. "I would say he's got a lot on his agenda and needs to focus on that. I think the world needs to keep him focused." Grylls himself remains laser-focused on climate change, which remains one of his signature issues. His latest National Geographic show, Hostile Planet, premieres on April 1 at 9 p.m. and takes a six-part look at the way climate change is impacting Earth's increasingly fragile ecosystem. "It really shows how animals manage to survive at the worlds' extremes, and how these extremes are changing because of climate change very fast," Grylls explains. "I think the message is it shows people the reality of what climate change is doing to our world, and one of the effects is the innocent party in this are the animals." For the record, President Trump is a pronounced climate change skeptic, which might make conversation a little awkward if he were to accept the Running Wild challenge. But Grylls says much of his younger fanbase is up to speed on the issue. "I don't meet many young people who deny climate change. There's no doubting that all of us should do all we can to protect it. If you have something, if you have something special, look after it." Hostile Planet premieres April 1 at 9 p.m. on National Geographic