Advicce for prep Alpine Challenge
 

So I decided to do the Alpine Challenge (Descanso version 61 miles) in San Diego east county April 28.

Quote from website "The Descanso Ride is unchanged this year and measures 61 miles and has 5,700 feet of elevation gain. It remains one of the toughest rides in California."

http://alpinechallenge.com/
http://alpinechallenge.com/pdf/RouteSheet62Mile2007.pdf

I should be in pretty good shape for this but I don't normally do this much climbing. Some of the roads in the ride are my normal training roads so it should be interesting. I am 50, started to ride again last year (February) after a 15 year hiatus. I have put in 500-700 miles per month of mixed climbing and flats about 5 times a week.

There is now 2 weeks to this event. How should a best structure my riding/prep/foods before this event? It is of course not a competition, but I just want to optimize the old body.

with only 2 weeks to go I wouldn't change your training routine - too much risk of injury, overwork. Sounds like you've done ample work to be ready for this. Hydrate well in days before.