How to increase speed while training for first marathon

[Aimee]

Thanks Sasha. I'm hoping to test my achilles with a short, easy run in a few days. Then I will build slowly. I may have to start with 3-4 miles at 9:30. That's okay, at least I feel like now I have a good feeling for how to move forward wisely.
Thanks for all the advice.

[steve ashbaker]

Sasha, Your assertion sounds logical on paper when you can control all of your lifestyle factors and variables.  But when you can't..  Also there are certain physiological systems that respond better to longer than average stimulus or intensity.  So therefore would not the length of the next day's run affect the recovery period, in effect needing a reduction downward in length and/or intensity to provide better recovery?   Both physiologically and mentally?   
Have you ever read the work of Dr Ernst van Aaken?  His ideas have given me some insight and guidance on how best to parcel out my efforts both long and short term in order to extend my running years as long as possible.  Very interesting stuff..