Pretty self-explanatory, lol.
Try using the search first next time… it only takes a minute! 
http://www.charliefrancis.com/community/showthread.php?t=7768&highlight=dorsi
The Forum Review Ebook covers this topic in depth. In the GPP DVD Charlie discusses exactly what your form should look like when sprinting.
I did search, I swear! I don’t know how the heck I missed that. My fault, everybody. I honestly did try to search; now I feel like an idiot.
Its cool. You searched for “dorsiflexed”, i searched for “dorsi”. Its just that otherwise we keep answering the same questions over and over.
That is what the products are for they distill all the information you need into a small amount of space and for the price they are unbeatable. I mean, 20+ years of Charlie’s training experience with the worlds top athletes discussed in detail. There really are no other sources of information like this aside from perhaps the products from Westside Barbell.