The most highlighted quote on his page is this:

  ...extreme fitness is less about being young again and more 
  about building yourself up for the years ahead. In other
  words, getting better at getting older.

That suggests to me a positive angle, not a stereotype. Being 48 myself, and having gone thru a less-intense version of what you’ve done, I think the quote nails it for me and the others that I know.

I actually think Baby Boomer generation deserves a lot of credit for pushing the boundaries, and our generation is following up in our own way. I can’t wait to see what the millennials do with this time in their lives.