If you haven't already, check out Chris McPeake's blog, called Suck it Up - Rantings of a Runner on the Edge. It's always a good & entertaining read. He's another guy in his 40's (there are a lot of us, aren't there?) and he puts in a LOT of miles. He's preparing to run his first 100-miler on May 29th. He's currently hosting a pretty cool giveaway, too.