http://sports.yahoo.com/nfl/news?slug=cnnsi-higherfasterstr&prov=cnnsi&type=lgns

Interesting article on how people prepare. The bit I found most interesting came during the intro:

"If you want a better idea of what I'm talking about, consider this tidbit offered by Detroit Lions strength coach Jason Arapoff. He broke down the number of snaps played by each Lion last season and determined that left tackle Jeff Backus led the team with 1,077 plays from scrimmage. Then Arapoff calculated how many seconds each play lasted to give me a sense of how much work Backus did over the course of 16 games. In all, Backus performed his job for exactly one hour and 47 minutes in 2004."