That was the question put to me by the Tampa Bay Times. During the AFC title game in which Manning’s Broncos defeated the Patriots, a replay showed Manning running for a first down in the 3rd quarter and hitting 17 mph (27 kph) on a speedometer graphic. To test the NFL’s speed claim, I needed to analyse video of the play. The best video I could get, however, was from the normal view we see on television (only quick looks from other angles). That side view meant that I could determine the component of Manning’s velocity parallel to the sideline, but not perpendicular to it. Click here for the article and you will see images I used of Manning in motion. From the 23-yard line to the 27-yard line, Manning was running mostly parallel to the sideline, but he did drift slightly toward the sideline while running those four yards. That part of his run represented the best shot I had at seeing Manning running parallel to the sideline, so that my speed calculation could be compared to what the NFL found. My guess is the NFL used overhead images, which would have been nice to analyse.
To give you a better feel for why it is challenging to determine speed from video, consider the screen capture below (click on the image for a larger view).
You can see the NFL’s speedometer showing Manning running at 17 mph. There is, of course, error associated with that number. What I really want you to see is the orange arrow I put on Manning. That shows approximately the direction of his velocity vector as he ran past the 21-yard line. My modelling of the run, therefore, began after he squared his shoulders and got moving more parallel to the sideline.
I found a maximum speed of a little more than 16 mph (26 kph), and I estimated an error of no more than 10%. Given what I had to work with, I would say the NFL’s speedometer was reasonably accurate. But as I mentioned above, an overhead view would have allowed me to determine his velocity vector instead of just the component of that vector parallel to the sideline.
Manning is listed at 6′ 5″ (1.96 m) tall and he’s been a great athlete most of his life. Athleticism and a long stride length help with speed (just ask Usain Bolt, whose height is about the same as Manning’s). Still, hitting 16 mph – 17 mph certainly isn’t bad for a guy nearing 40 years old!