A couple days ago, Deadspin provided an excerpt from an article discussing sleep patterns and the NFL, and it brings up some fascinating points. The excerpt is from David Randall's book Dreamland: Adventures in the Strange Science of Sleep.
The basic point is that due to an advantage in the sleep cycle, teams on the west coast have done extremely well on Monday Night Football when they have faced teams from the east coast. Football Outsiders took a look at the list of games in question, and since 1995, the West coast was 16-5 over the East coast. Even if you remove the dominant 49ers teams from the '90s, the numbers seem to stand up.
According to the author, circadian rhythm provides that people generally perk up at 9am until about 2pm. They start to drag, but get another burst of energy from 6pm to 10pm. From there, body temperatures start to fall, and humans get sleepy without a jolt of caffeine.
The idea is that with Monday Night Football starting so late, west coast teams are getting right into their zone, while the bodies of east coast teams are starting to wind down. It is of course worth noting that this is a very small sample size, and it is hard to tell if the sleep factor is the issue.
Nonetheless, it is intriguing to consider just what the human body can do to impact a game. This research was only on Monday Night Football, so the author did not address whether Sunday Night Football would have a similar impact. It seems to me like it should, but I'm no sleep scientist. Thursday Night Football would seem to create a separate wrinkle entirely as we saw with the 49ers quick turnaround against the Ravens last year.
The 49ers don't face east coast teams on Monday Night Football, but they do get the Lions at home and the Patriots on the road for Sunday Night Football. Maybe this is something to factor into projections for the game? Maybe Football Outsiders can do some research on Sunday Night Football results to tell us more.