I think 13 weeks is a typical marathon training period, starting from a ten-mile base, so the July Century should be a thing of the distant past by 2007.
I've also found that cycling improves my running, but watch out, I also found out that I love cycling so much that running seems like a chore now.
Another good thing- once you get a nice cycling base, it's very easy to maintain. Believe it or not, soon rides in the 60-80 mile range will seem like a piece of cake.
Nanci
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"...I'm like the cycling version of the guy in Flowers for Algernon." Mike Magnuson