I used to love Bear but it turned out his show wasn't quite as honest as they made themselves out to be
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Later it was revealed that much of his sequences were faked, staged or that Bear got a lot of assistance from outside sources. For a while they pulled Man vs. Wild from the Discovery Channel. When they finally brought it back on, they put in a lot of disclaimers and edits to say that the show was more of a guide, like "what to do in this situation", rather than a reality show. Now they fully acknowledge that Bear gets assistance from an survival expert and that some of his stunts are for demonstration purposes only. He's no slouch though, he really eats those things and he does put himself in some danger.
But Les is the real deal. He's litterally on his own the whole time which is why he looks a lot worse for wear at the end of his show. Also, he's lugging around a ton of weight in camera gear, and most of his distance shots of him walking toward or away means he needs to make that trip twice just to set up or retreive his camera. That's pretty hardcore.