For all of us who want to continue our outdoor pursuits well into our 70s, 80s and 90s, I highly recommend the "Younger Next Year" series of books by Chris Crowley. He's 87 and is still doing downhill skiing, rowing, long distance bicycling, etc. As some of you have already mentioned, functioning well into your older years is largely about diet and exercise. I found this series of books to be really entertaining and informative.

Nothing the government gives you is free.