Well, Mike Douglas in this video was 40; at 3:21 he says one of his last goals in skiing was to do a 7 at 40. Pretty sure the man still slays pillow and powder to, hucks cliffs, all the good stuff. So in the freeskiing sense of things, he has to be one of the oldest.
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Now Plake and Wong and those guys, not really sure what to say about them because sure ya theyre still skiing and whatnot but I dont think there really out there charging that much, but maybe Im wrong. So sick to see the older generation rip it up though!