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Usain Bolt and NFL combine 40 times

Posted by Doug on August 21, 2008

Let me preface this by saying that almost every single word of what I'm about to write could potentially be incorrect. I don't really know what I'm talking about. Possibly the most reliable source I've used here is Wikipedia, if that tells you anything.

But you guys will help correct me if I say something really stupid, right?

It all starts with a message board post from a guy I don't know that I saw linked from another message board.

Usain Bolt's splits during the Olympic 100m race

RT 0.165
10m 1.85
20m 2.87 (1.02)
30m 3.78 (0.91)
40m 4.65 (0.87)
50m 5.50 (0.85)
60m 6.32 (0.82)
70m 7.14 (0.82)
80m 7.96 (0.82)
90m 8.79 (0.83)
100m 9.69 (0.90)

30m is 32.8084 yards. So he needs to cover 7.1916 more yards from there.

He ran from 30m to 40m in .87 seconds, or .087 seconds per meter, or .0795528 seconds per yard. But he wasn't at top speed yet. So the first 7 yards of that would have been slightly slower than the average of the full ten meters, but faster than the .0832 seconds per yard at which he ran from meter 20 to meter 30. So let's say he averaged a nice round .08 seconds per yard. Multiply that by 7.1916 and you get .575. Add that to his 30m split and you're at 4.35 or 4.36.

So unless I've done something wrong, we have the following:

At 40 yards of the actual Olympic 100m race, Bolt was at 4.35 or 4.36

But wait...

His reaction time was .165. My understanding is that the combine 40 is timed from the runner's actual start rather than from a gun. So if this were in an NFL combine setting, that reaction time would be gone and he'd be at 4.19.

But wait...

There are no starting blocks at the NFL combine. And my understanding is that this particular Olympic track is the fastest around. Those two things would push his NFL combine time up over 4.2, maybe up to 4.25 or even 4.3.

But wait...

If he were training specifically for the 40, he might be able to do some things somewhat differently to shave a few hundredths off.

I hereby declare that Bolt would run a 4.22 at the combine.

Chris Johnson ran a 4.24 at this year's combine. Does that make my Bolt estimate seem too high? Or does it mean that the timing at the combine is inexact or inconsistent or just plain generous? Could be either one --- or both --- but I'm not totally sure the two figures are incompatible. It was around the halfway point that Bolt really blew everyone else away; I don't even think he was leading at 40 yards. So it's not clear to me that Chris Johnson couldn't hang close to him for 40 yards.

This entry was posted on Thursday, August 21st, 2008 at 3:44 am and is filed under NFL Draft, Non-football. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.