Why a Legion Sprinter is so Hard to Beat

Legion of Los Angeles Sprinters

April 11, 2021.  That was the day that criterium racing came back to Southern California with the Majestic Criterium in Ontario, CA. The turnout was incredible and it really showcases how desperate we all are for social interaction and real-life competition.  The action did not disappoint as onlookers were treated to a number of dynamic races on the day. This culminated with the Pro-1-2 event which featured the UCI CT: L39ion of Los Angeles. As I watched the finale, I couldn’t help but think about how hard it must be for anyone in the race to win if you’re not a Legion sprinter.  

Here’s a good highlight video made by Cory Williams.  

Justin and Cory finished first and second with a UCI CT: Elevate Webiplex Pro Cycling rider third to round out the podium.  What happened in the parking lot afterward served as the muse for this entire piece. I happened upon another team’s post-race meeting where they reviewed the race and provided a lot of great feedback to each other. (I think this aspect of the race is lost on many current teams. Debriefing is normal for successful teams.) During my eavesdropping, the team appeared convinced that the way to beat the Legion sprint hammer was to bring a bigger hammer to the sprint.  Great concept and also reasonable: Be better than your opponent and you win. But on the drive home I started thinking about how unreasonable that is exactly. 

First, I want to dispel the notion that anyone can win a sprint finish. That idea is 100% false. Sprinting is a specialty skill the same as downhill, 100m dash, quarterback, or pure climber. The truth is that in any high level criterium there are only about 4-6 athletes that are capable of winning that day and, spoiler alert, unless you’ve won a field sprint in the last 2 years, that’s not you. Taking a sprinter to the line and believing you have a chance for success is akin to taking a climber to the base of climb believing you’ll outclimb them.  

Before we get into the finer details, some concessions and declarations: 

The fluid dynamics of drag (air resistance), impulse (acceleration), and all the concrete numbers that some of you want simply isn’t going to happen. There are too many variables in a real-world example to calculate. I’ve waded into the internet to get some good references and tools.  I also make some assumptions like that the drag coefficient and frontal area of Justin and an opponent are the same. The point isn’t to make it exact but to give you an idea of what it would take if you wanted to beat the Legion sprinter by bringing a bigger hammer.

Here’s the websites I used for reference; there are undoubtedly more complicated and comprehensive ones: 

You’re also going to see Justin’s numbers. Sure, that’s a big deal but, is it? We can all follow Mathieu Van der Poel on Strava and see all his training/ racing data. So what? That’s analogous to hitting off a particular pitcher in baseball. Teams know what pitches will be thrown, how fast each pitch will be, how much displacement per pitch, and when they’re most likely to throw a certain pitch. But… you still have to hit the ball.  Knowing the data is only as good as knowing the data. MVDP’s data is basically public knowledge but it hasn’t affected his results much.

I completely understand that a lead out is a prerequisite for success in a high level criterium. However, besides mentioning that the lead-out was “textbook”, I’m going to leave that alone unless you want this to turn into a chapter book.  

Finally, some finer details… 

First, let’s watch that video again. Fast forward to 3:20 if you want to see the sprint from Cory Williams’ first person camera. 

Note that Legion sprinter Justin Williams stops pedaling for ~2 seconds before crossing the finish line.  That’s important as it contributes significantly to his deceleration which will make all the calculations lower than they would be had he kept on the gas the entire time, like in Tulsa Tough. Here’s what that Majestic sprint looks like from the power file: 

Sprint Peaks

Cycling fans repeatedly hear the phrase, “drop the sprinter off at 200m to go” without any real explanation of why. Sprinters, spectators, and announcers use the 200m landmark in a race because it’s typically 10-12 seconds to the finish line. Using 40mph as a standard, that makes it 11.11 seconds to the finish. This means the 200m cycling sprint and the 100m dash are analogous in many ways. There is an acceleration phase of 50% (5-6 seconds), hold maximum velocity for 30% (3-4 seconds) and decelerate for 20% (2-3 seconds or anything after 10-11 seconds total). Because of the draft advantage, any sprint longer than 14 seconds exposes the sprinter to the dramatically increasing possibility being passed during the deceleration phase, which is why dropping off the sprinter too early can be catastrophic. If Justin can keep his sprint to 14 seconds or less it makes the task of coming around him exponentially more difficult. 

Here’s Justin’s sprint with those 100m dash sprint phases: 

3 phases of the cycling sprint

Breaking down the numbers, the first thing I noticed is that Justin’s entire sprint was ~330m vs the 200m mentioned before mostly because of speeds attained during the lead out and sprint. Justin spent 12-13 seconds actively sprinting before the victory was secure. That’s exceptional because it means the final 19% of the sprint was immaterial as he was able to soft pedal and coast to the line for the last 3 seconds. But those first 13 seconds are incredibly violent. Justin’s power amped from 934W on Cory’s wheel to 1777W in under 2 seconds (power meter sampling size limited to 1s intervals. That 0.25s increment feature is the only thing from SRM that I miss today). Simultaneously, his speed accelerated from 32mph to 44.7mph in 11 seconds. I’m pretty sure my first car in high school wasn’t able to do that. Sprints like this are in the +19w/kg realm which ranks the effort firmly as a “world class” performance. 

But how is beating this sort of sprint possible? There’s really only two realistic possibilities: 

Bigger Hammer than the Legion Sprinter

We will assume that an athlete is able reach a higher top speed, which will require a higher peak power. Plugging some general data into this calculator and this to help while making the assumptions I mentioned before and we learn that a 165lb rider that is perfectly placed behind Justin needs to make in excess of 1840W in order to ride at 46.2mph (speed needed to make the pass at 44.7mph in under 320m). That effort would look something like the dotted line in comparison below. It seems “easy” enough right? 

cycling spring bigger hammer

Swing the Hammer Longer than the Legion Sprinter

The second possible scenario is to take advantage of that deceleration phase by holding a similar or slightly lower power but higher speed during the deceleration phase. Justin’s 16 second sprint, including the non-pedaling time, clocks in at 1153W average output with an average speed of 41.5mph. Looking closer at the deceleration phase, those last 4 seconds are at 42.6mph average which means an opponent needs to hold 43.8mph to make the pass in that last 4 seconds at an output of 1528W. That type of effort would look something like the below picture. The athlete would need to match the acceleration by Justin then have less drop off at the end allowing for the maximum velocity phase to be longer and the deceleration phase to have a higher speed. 

swing the Hammer longer cycling sprint

Final Notes for Beating a Legion Sprinter

Many readers are probably thinking “this seems pretty straight forward.” To some degree it is. Remember, that we’re making the assumption that this is what is required for that one lucky and battle-hardened rider who has that super sweet drafting spot on Justin’s wheel to make a pass. Unfortunately, in the last 10 minutes of a race, that’s probably the most contested piece of real-estate in the race. Next time you watch a sprint finish on TV focus on the space directly behind the favorite’s wheel. That should provide some perspective.

But more importantly is that air conforms to the fluid dynamics of drag. In simple terms, it means that the power needed to overcome wind resistance increases exponentially as your speed increases incrementally. It’s a tough concept and very few are actually good at grasping the magnitude of exponential gain. Here are some examples using that 165lb rider riding an “in the drops” position: 

As the required output gets more extreme the number of athletes capable of attaining those numbers dwindles rapidly. The term “world class” rightly assumes that those who can perform at that level are the best in the world and also that there are very few capable of the same performance. Also, consider that an athlete capable of a 1200W sprint for 14 seconds would average 40mph and finish almost 31ft behind (9.4m).   In true romanticized fashion the only athlete who has the capacity to outsprint Justin, who sprints at a world-class level, is another athlete that also sprints at a world-class level. 

justin williams sprinter

Had the team in the parking lot asked me for my thoughts during their debrief, I probably would have thought about everything above. Then I would have looked around at them and probably said something like, “The peloton racing today is full of people that want to win. Unfortunately, only about four people are capable of winning and none of those four are sitting here right now. It’s not an insult to anyone here right now but the simple truth is that, among those who were in the race that day, no one except Justin or Cory was capable of winning. 

Source Endurance has worked with a number of the Legion athletes including Cory and Justin Williams since 2016. During that time these two athletes have evolved as athletes and people to become not only superb riders in their own right but also an inspiration to others. 

Thanks for reading. Ready to learn more? Check out: How to Make Winning Look Easy: Team Edition.

About the Author: Adam Mills MSED, RCEP has raced at the elite level since 2002 and graduated with a Masters Degree in Exercise Physiology from the University of Kansas in 2005. His true talent comes with his ability to combine his vast experience with his knowledge of sport. He is indeed a student of science, sport, athletic performance, strategy, and tactics. He continuously educates himself by keeping up to date with current research trends and methods in sport and his clients have reaped the benefits from this work with over 17 national championships in 11 disciplines on two continents. Adam is able to incorporate these attributes on a daily basis to help his clients reach and exceed their goals whether they are a beginner or a seasoned professional. Learn more about Adam and Source Endurance here.