Photography by Cor Vos

Tiffany Cromwell’s Omloop Het Nieuwsblad Power Analysis

by Wade Wallace
and Helen Kelly - March 2, 2013

As most of you will know Tiffany Cromwell won Omloop Het Nieuwsblad last weekend and I had the opportunity to interview her a few days ago. I thought it would be interesting to do an analysis of Tiff's SRM data from the race to put into perspective how good these girls are. Tiff was generous enough to oblige and send me her files. I've ridden with Tiffany and some other top women cyclists in the world and let me tell you, they've given me a whoopin'. This one's for you power geeks out there. Have a look and don't let the graphs intimidate you ...

I asked Helen Kelly of Kelly Cycle Coaching (Melbourne) to help me with the analysis since she trains all her athletes with Training Peaks and is very familiar with the software. Not only that, Helen use to race at an international level and in the final race of her professional career, she was in a breakaway with Tiffany Cromwell as a young amateur at the Bay Crits (the Geelong hot dog circuit on Richie Blvd). They both stayed away for the entire race and Tiff attacked on the bell lap but Helen got to her by the final corner and just came around her moment before the finish. Helen was at the end of her career, Tiff was at the start of hers.

Anyway, back to Tiff’s power analysis. A few facts and observations:

Tiffany weighs around 49-50kgs.
Tiffany’s threshold power (tested in January) is 229 watts. This equates to a threshold power of 4.6 watts/kg.
We’ll see male pros at the top of climbs with threshold power levels of 6.2w/kg, and back in the day it was closer to 6.9w/kg.

We can also see from the charts below a few interesting things:

Tiffany appears to be very good at keeping her nose out of the wind, because she spent 25mins below 60w and 30mins at 60-120w (i.e. in her recovery zones). This basically means that she was able to conserve a lot of energy when she could. Even more so, with her overall average numbers being so high, it shows that when she was going hard, she was going extremely hard! For 73 minutes she was over her threshold power.

Another thing to take into account are the cobble sectors and how much more effort they require than smooth roads. Also keep in mind that the point of racing is to conserve as much as possible until the decisive moment. Only use what you need and save everything for the finish. If you expect higher power figures because you’re use to hearing the men’s wattages, keep in mind through all of this is that Tiffany weighs only ~50kg.

Stats

Total race time: 3:36
Average power 175W
Normalised power 206W
TSS 292.9
IF 0.903

Let’s get more into these power stats during the key moments of the race.

Distribution Graphs

Here you can see the distribution graphs for speed, cadence, HR, and power. Things to take from this: Don't pay much attention to speed -- it means nothing in a race; Tiffany's cadence was a nice 80-90rpm for most of the race. Her power was either very low, or above her threshold, and HR was in the 160bpm area for much of the race.

Full Race Data

This is Tiffany Cromwell's overall Omloop Het Nieuwsblad graphs for power (top), heart rate (middle) and cadence (bottom) for the entire 3 hours and 36 minutes of the race. From this you can see a couple of things. Her average power was 175W (she weighs 50kgs), her normalised power was 206W and she burned 2244kJ. What's really interesting is that her TSS (training stress score) was 292.9 (which is massive) and her IF (intensity factor) was 0.902. TSS is a Training Peaks metric (this is the software we're using). Basically what it means is that 1hr spent at your threshold would equal a TSS of 100. Tiffany nearly scored the maximum achievable TSS each hour she raced. Same thing with the IF (intensity factor). The maximum possible IF is 1.0. Tiffany scored just under that (IF is used to calculate TSS).

Final 20 Kilometers

This shows the final 20kms of Omloop Het Nieuwsblad where Tiffany was in the final break. With all eight climbs completed and five cobbled sections yet to come, a 16-rider front group formed. There were multiple attacks from many riders but nothing stuck. You can see that Tiffany averaged 224W (just under threshold) in this period before she made her final move which won the race.

Cromwell attacks before the final pavé sector with 11km remaining. "We had been using our numbers to our advantage and launching attacks that were going nowhere," said Cromwell. "Finally, I went and Megan Guarnier came with me. We got a gap immediately but she wasn't working with me. I still considered it a good opportunity, so I worked - maybe a bit too much. Eventually Megan started rolling through. It was enough to hold off the chasing bunch."

The Final Attack And Sprint

This graph shows where Tiffany made her final attack 11km from the finish just before the final pavé sector. She put out nearly 700W in her attack and then held a normalised power of 240W for the final 17mins. Her max HR was 173 and she had an average speed 34.7km/hr in that last section of the race. We can see the power spike at 300m from the end where Tiffany tops out at 749W. At approximately 50kg, this is normalised to 15w/kg. The highest ever recorded peak power from a female at the AIS that we could find is 16w/kg.

Cromwell forced Guarnier to the front just before the final kilometre. With a long sprint still to go, Cromwell came around Guarnier to open up the sprint but Guarnier nothing left to react. "I started sprinting with 300 metres," Cromwell said. "Megan didn't contest the sprint. I don't think she had anything left."

Thank you to Tiffany for sharing her SRM data with us and thank you to Helen Kelly for breaking the data down for us.

Click here to read Tiffany’s interview with CyclingTips.

Tags: power, Tiffany Cromwell

http://twitter.com/cyclist_dave Dave

Nice data.

A few years ago in the break room at work I saw a letter in the newspaper complaining about how sports were sexist, arguing that women should be allowed to compete against men in the Tour de France if they were strong enough. I commented that “all those women are competing — there aren’t any”. One of the guys looked at me as though I was some sort of misogynistic pig, but then I got to explain…

As for this data, Tiffany is about as strong as anybody, but the canonical power chart (put together by Andy Coggan) — https://s3.amazonaws.com/cyclinganalytics/static/cycling-power-table.png — indicates that pro women normally have a threshold power closer to 5.5W/kg. Any idea what’s happening here?
- http://twitter.com/rgmerk Robert Merkel
  
  With all respect to Andy Coggan, I don’t believe that’s a plausible number for the top women. I would guess the top climbers (Pooley, Vos) would be somewhere in the low 5s and the rest of the women’s field somewere in the mid-4s and above.
  
  Tiffany is one tough cookie (if just looking at her SRM data didn’t convince you). If you have a look at the recent history of the men’s event, it’s all Classics hardmen. For a flyweight like Cromwell (even in the context of the women’s peloton, 50 kg is pretty small) to win is pretty damned impressive.
  - http://www.facebook.com/acoggan Andy Coggan
    
    “With all respect to Andy Coggan, I don’t believe that’s a plausible number for the top women. ”
    
    Guess again. :) There are, indeed, professional women who can generate >5.5 W/kg for ~1 h. No one is going to put them on a men’s TdF squad (except perhaps for the publicity), though, because that’s not enough to be competitive on GC, and they don’t produce enough absolute power/generate enough of a draft to be a good “worker bee”.
    - http://www.facebook.com/acoggan Andy Coggan
      
      (BTW, if you believe that the best male cyclists can generate 6.2 W/kg sans doping, then 5.2 W/kg is clearly too low for the best women. The typical sex difference in VO2max - which sets the upper limit to sustained power output - is ~10%, with that difference tending to be reduced at the elite level due to the lower-than-average body fat of elite female endurance athletes.)
      - jules
        
        i propose a new guest post from andy coggan! you know it makes sense.
        
        http://www.facebook.com/acoggan Andy Coggan
        
        I’d say “happy to oblige”, except the analysis that I’d really like to do is something slated to appear in WKO+ 4.0, so I couldn’t reveal the results yet.
      - http://www.cyclingTipsBlog.com cyclingTips
        
        Thanks for stopping by Andy and leaving your feedback. Invaluable information.
        
        BTW, are you saying that you don’t believe that 6.2W/kg is improbable for males without doping? I interviewed the late Dr. Aldo Sassi and he suggested this is the upper limit: http://www.cyclingtips.com.au/2010/09/interview-with-dr-aldo-sassi/
        
        Nick
        
        I believe he’s saying that 6.2 W/kg *is* believable, and that 5.2 (ie, “low 5s” in the parent comment) is too low.
        
        6.2 - (0.1 * 6.2) = 5.58 W (ie, The “typical sex difference in VO2max - which sets the upper limit to sustained power output - is ~10%”)
        
        Nick
        
        I believe he’s saying that 6.2 W/kg *is* believable, and that 5.2 (ie, “low 5s” in the parent comment) is too low.
        
        6.2 - (0.1 * 6.2) = 5.58 W (ie, The “typical sex difference in VO2max - which sets the upper limit to sustained power output - is ~10%”)
        
        http://www.facebook.com/acoggan Andy Coggan
        
        Correct.
        
        Sean
        
        Thanks to Tiff for sharing her data file. There is a distinct lack of pro female cyclists data available for view & comparison in the public domain. It would be great to see some more female data files submitted for review.
        
        Andy, besides what may be theoretically possible, do you have any idea what likely w/kg would see a female podium for a long hilltop finish at the pro level in 2013?
        
        http://www.facebook.com/acoggan Andy Coggan
        
        Mid 5s, possibly higher…it really just depends on who is there and/or how the race plays out.
      - The Potato Man
        
        Might be worth noting that Tiffany Cromwell isn’t really the type of rider to need a high threshold power to weight i.e. not a time trialist or climber. She is more of a punchy rider/opportunist, similar to maybe Gerro . . . ?
        
        Well, that is my understanding at least.
    - http://twitter.com/rgmerk Robert Merkel
      
      Fair enough…who am I to argue with the guy that wrote the book on power training?
      
      But we can go back to Dave’s original comment : if the top women pros can do >5.5 W/kg, what’s a 50kg rider with a threshold power of 4.6 W/kg going off the front of a women’s pro peloton?
      - http://www.facebook.com/acoggan Andy Coggan
        
        As The Potato Man implied with his comment below, it could simply be that there are “horses for courses”. That said, I’m actually a *bit* surprised by her data/this race result as well. But, I haven’t looked at the course profile or how the race played out, so can’t really say anything for certain. It does appear that her functional threshold power is indeed ~230 W (measured using that power meter, anyway), as her power frequency distribution histogram shows the classic “step down’ past that bin.
Why give them air time?

Do we need a ‘back in the day’ power figure? Doping deserves no more air time than it presently gets, this includes throwing in power figures from when guys were on the juice (and when you would expect to see w/kg of 6.9).
- http://www.cyclingTipsBlog.com cyclingTips
  
  I actually do think the “back in the day figure” is a good relative comparison to put some perspective on what’s realistic and how things are hopefully cleaning up. Would you prefer me ignore what’s happened in the past? I’m not sure that’s a good way forward.
  - jules
    
    if we didn’t keep quoting old power-weight figures, we wouldn’t know who to label as dopers today, based purely on their performance :-)
Jii

Tiffany thanks for being willing to share that data, it is a fantastic insight to have. Unbelievable numbers ~3hours at or above threshold!
Pete

I think if I ever had this type of data i’d die of laughter at just how bad the figures would be…
Pete

I think if I ever had this type of data i’d die of laughter at just how bad the figures would be…
Marko

You cannot do 3 hours above threshold. That is not how it works. Threshold is the the onset of blood lactate accumulation (OBLA) usually accepted (though varies from athlete to athlete) at around 4-5 mmol/l blood lactate concentration. If she did 3 hours above threshold then the quoted threshold is in my opinion obviously wrong. Either her threshold training since January has been really effective, or her ability has improved remarkably since January for some other reason (you figure it out), or the sport physiologist who did the threshold testing got it wrong. 229 Watts is not high for someone producing 750 watts peak power and I suspect the January threshold test was flawed. Just saying…
- http://www.facebook.com/acoggan Andy Coggan
  
  The power distribution indicates that she spent 73 min, not 3 h, at or above her FTP. That is certainly quite possible, especially given the fact that we talking about a mass-start race and such “time in zone” analyses don’t tell you how long each “foray” above FTP lasted.
  
  As I indicated below, provided her SRM is properly calibrated her FTP does indeed appear to be between 220 and 240 W, as it beyond that bin in the frequency distribution histogram shows the classic “step down”.
  
  There can be considerable variation between individuals in the relationship between maximal neuromuscular and functional threshold power, so knowing her 5 s power really tells us nothing here.