Sad to say, this stuff will catch up with you sooner or later, unless you live a very charmed life. It is a testament to the general ruggedness of the human body, and the strength and stamina, and physical conditioning of these guys that some of them persevere and survive into their middle years before starting to wear out. I hope he recovers well and can continue his vocation without too much trouble.

Not even close to what these guys were doing, but I used to go "wandering about" in the greater Mojave and Sonoran Deserts a lot in my youth, and even now, from time to time, and after a day of romping over hill and dale, dry wash and rock field, I hurt, no matter how easy and careful I try to be.

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