I think self-challenge is a great thing, but I never understood CEOs whose understanding of self challenge is basically confined to the physical realm - training like Navy Seals, motorcycling, climbing difficult mountains, doing an ultra marathon, etc... You can challenge yourself on a lot of levels, but it always feels a little brute when it&#x27;s only physical stuff.<p>Of course to truly broaden yourself, to grow in the deepest, meaningful ways, you won&#x27;t have time to do it if you&#x27;re a CEO.