For the nerds: Frankfurt bike in numbers

To finish off our reports on Frankfurt I'm going to dig a little into the numbers of the bike and the run. Alain and I are both using Power2max power meters (thanks again for the support!), and so we can compare pretty accurately how the race played out.

A quick reminder on Alain and me in terms of numbers:
Alain is a little over 1m79 tall, weighed 69kg on race day, and has a swimmer's body with a long torso. He has an FTP of 320-330w (4.6 w/kg) and rides a Cervelo P3 - his position is just beautiful to look at.

Nico is 2m tall, weighed 84kg on race day and has long legs. He has an FTP of about 390-400w (also 4.6w/kg) and rides a no-name frame. His position isn't too bad, but the tall bike makes for a less beautiful look.

How it happened
The first 15km into Frankfurt is pancake flat. As the race starts people are still close together, which makes for fast riding. Then the course turns to the first hills around km 30.

Over the first 45km Alain took 1h16 (35.2kph average) for a normalized power (NP) of 230, or 3.3w/kg. He was riding with a nice and high cadence of 91 average and rode evenly - a variability index (VI) of 1.06. 

Nico on the other hand took 1h10:51 (37.8kph average), making up more than 5 minutes over the first quarter! His NP was 268 or 3.2w/kg. He was riding with a lower cadence of 85 and had a higher VI of 1.1. His pulse settles after the swim and he bikes at 131bpm.

It looks like Nico benefited from the group effect of a crowded field at the beginning of the race whilst Alain was riding alone for the first 30km. This shows the importance of tactics even though drafting is not allowed: Alain might have been able to save substantial time by hurrying in transition and sticking with strong riders in the early stages whilst the field was still close together. He led a big group out of the water who he might have been able to work with.

Over the second 45km Alain increases his power slightly to an NP of 236 (3.42 w/kg), takes 1h14:23 (36.2 average) for the section, and keeps his smooth and fast cadence (89 average). His VI stays at 1.06.

Nico continues to gain, but less so: his NP goes up to 284 (3.38 w/kg), he takes 1h13:23 (1 minute gain, 36.7kph average) and he increases his cadence to 87. His VI is coming down to 1.08 and as does his pulse with the cold - now an average of 124.


Alain covers the third 45km in 1h15:54 plus a one minute stop to go to the toilet. He rides is average of 35.4 with 232 NP (3.36w/kg) and and his cadence is now very variable since he is having problems with his gears. This also shows in his VI which shoots up to 1.15 as he has to motor on the climbs and spins out on the descents.

Nico covers the third segment in 1h12:30, making up another 3:24 on the road (4:30 in total). His average of 37.1 comes at a NP of 281 (3.35w/kg), with a slightly higher VI again of 1.1, and his pulse stays at 125.

Over the final segment Alain 1h19:31 for an average of 34.7 and at an NP of 243 (3.52 w/kg)! He is clearly suffering from the lack of gears and the wind is slowing him down. His cadence has dropped to 77, but interestingly his VI is down to 1.05 - he is grinding it out.

Nico takes 1h18:06 (34.9avg) over the last segment at 272NP (3.23 w/kg). The legs are getting heavy and the wind is taking its toll. We see the heart rate drifting up again to 130 despite the lower watts - indication that he is tiring (or that the warmer weather is having an effect as the sun comes out). His VI is down again to 1.05 and the cadence is up again as the power in the legs is going.

Overall

Nico outpaced Alain by close to 12 minutes. Interestingly he did so at a lower weight to power (Alain's 3.42 w/kg to Nico's 3.29). This shows us the advantage of being a big powerful athlete on a short course: speed is more related to frontal area than to weight, and frontal area increases more slowly with size than weight. On a course like Nice Alain would very likely have been faster than Nico, if he would have found his climbing legs :-).

The second interesting thing is that tactics matter a lot when the race is flat: the advantages of riding with other people cannot be denied, even at 10m there is still a draft effect. Nico got some easy minutes on Alain in the first part of the course - it seems that race tactics prep worked :-). Details like a transition that is 30s faster or slower can make a big difference.

The data also shows us the sheer amount of energy needed for an Ironman bike split: Alain produced 4012kj of energy, which takes about 4500cal and Nico put out 4527kj, which takes upwards of 5000cal to produce. Keep eating during the race!

Tomorrow we'll look at how the run panned out.