Tuesday, March 8, 2011

Analyzing the Tour of New Braunfelds Criterium Sprint

Every now and then we'll have an athlete produce a break through performance that truly is worth talking about.  Jed Rogers sent me this file a while back his finishing sprint immediately stood out, mostly because it was definitely better than I expected to see for February.  Jed has worked hard in the last few months to overcome a 2010 ending injury which required a good deal of off the bike work just to get him back onto two wheels.  Since then, the focus has been on getting him able to reach the finish line.  Obviously, the best sprint in the world makes no difference if the rider can not get to the finish line.  Perhaps this makes the final two minutes of Jed's race even more intriguing because his effort proved the best of two worlds: a superb sprint with lots of power but also a lack of sprinter "sharpness" as shown by some miscalculations which ultimately derailed an opportunity for a February win.

Let's start by looking at the final two minutes of the race:

Final two minutes. Yellow: power (dotted lines every 250W), Blue: Speed (dotted lines at 30 and 35mph).
The first thing to notice is the steep ramp of the power output. This is fairly indicative of a field sprint.  You can see how the power fluctuates erratically as Jed battles and maneuvers to maintain his position.  But where things get interesting is the last 560 meters. 

The numbers of the last 2 minutes are fairly impressive in and of themselves but they are even more so when you examine them more closely in the context of the sprint.  For all you numbers folks: 
Work complete: 57kJ
Average Power: 482W
Average Speed: 31.2mph.

And the numbers of the last 35 seconds....

Final 35 seconds: 
Work Completed: 31kJ
Power (min, max, avg): 0, 1384, 910 W
Speed (min, max, avg): 30.8, 37.6, 34.8 mph.

Final 35sec: Yellow: power (dotted lines every 250W), Blue: Speed (dotted lines at 30 and 35mph).
In the last few seconds of the race, Jed describes the sprint from his vantage point:

"I found myself at 550m or so and was way too far back so I had to make a move to get into position."  This is the initial acceleration from 30-34 mph that does not show here.  From there Jed was looking for a place in line to punch in, grab a quick 'rest' and sprint.  However, right as he was beginning to get settled a fateful series of events ended his chances of victory.

"Just as the winner was jumping, I had to stop pedaling, juice my brakes, and maneuver around in search of daylight to sprint."  This can be seen as the power curve nose-dives, along with a 4mph decrease in speed (12%).  But more importantly was that all of his relative forward momentum was gone and all the energy invested thus far to make that move happened had to be reinvested in order to hold even.  And hold even he did. 

"In the end, it was the top 3 of us, all frozen in place but all sprinting as hard as we could while not gaining on each other." Jed comes back with an incredible ~1400W effort after 3 previous 1000W efforts in the last 20 seconds.  This effort not only gets him up to speed fast but re-accelerates him beyond his 34.8mph to 37.6mph. That in and of itself is an amazing feat and not something that most bike racers are even capable of producing!

Jed finished 3rd in this race.  However, the things he learned will pay dividends forever.  Also, the sprint data provides some superb insight to what a sprinter of his caliber is capable of.