OLH power analysis

I've neglected my blog. I admit it. Hopeless neglect.

It's not for a shortage of material: I've had event reports, analyses, and opinions ready to go but abandoned due to an obsessively dedication to coding various Strava projects. Any project has a deadline, written or otherwise. Get it done or other priorities will displace it, it gets pushed to the back burner of good intentions, and there it will congeal, momentum lost, trajectory forgotten. I desparately didn't want that to happen, so I've been trying to squeeze every available snippet of time into getting the thing up and running. Unfortunately "snippets of time" aren't the best way to make coherent progress on tasks of any complexity. A day or two of dedicated work is far better than even a month of 30 minute bursts. It's why the "hack-a-thons" are popular: 24 hours straight of total focus can actually accomplish something.

So I've not gotten past the unanticipated hurdles as gracefully as I'd have liked. Some of this has had to do with pecularities with the Strava API. But I've also committed my share of bugs.

Anyway, this past Wednesday I did the noon ride with my PowerTap. This has been a rare occurrance for me: I rarely make the time for the Wednesday Noon Ride, since it results in a 2 1/4 hour lunch. But even when I do make it, I usually have my Ritchey Breakaway with conventional rear clincher wheel due to the random tribulations of strapping bikes onto the crowded racks of Caltrain. Nicked spokes and chipped clearcoat are SOP.

Despite having felt under the weather, including digestive discomfort, and clogged ears and sinuses, I cashed in some of my 2.5 week investment of lunch-at-the-desk for a Wednesday nooner. For a bit last year the Wednesday Nooner had been a rare warmup-plus-race-up-OLH affair, very nice for chasing good times there, but the two times I've done it this year it's been definitely on the friskier side up Alpine Road.

I hit the base of the climb in good position. XXXXX set a really strong pace right away, and I slotted in to follow. But within a short time it became clear that the this pace was going to be unsustainable. I looked at my power meter and was seeing well on the wrong side of 300 watts. I like to believe I can average 280 to 290 watts up Old La Honda on an optimal day, but given the variable grade, that means on steeper portions I've got to see 300 to 320. However, this was too high, so I slotted it back.

As I let the gap open, YYYY then caught me and shouted something to me. I wasn't sure what he said, but as he rode past he repeated: he wanted to know if I was intending to follow the leader. No, I told him -- "too many watts".

So I slowed it back down and tried to ride my own pace the rest of the way. Near the top I started to feel myself unravel. It became increasingly difficult to keep my power at 280 watts or higher. I felt like I was losing more when the grade lessoned, slumping into the low-200 watt range rather than accelerating to accomplish the lower grade. This caused me to desparately try to compensate when it got steeper. The clock was ticking.

I wasn't the only once suffering. XXXX appeared up the road, clearly paying for early enthusiasm. I passed him, hopeful YYYY wasn't much further. But he was long gone.

But I managed to reach the end game before total melt-down. In the final few hundred meters I always find a way to crank it to the next zone, since "sustainability" is no longer an issue. And I finished.

My Garmin showed 17:59 when I crossed the line. This was almost 1.5 minutes slower than the PR I set back in December. I felt crappy, drained, a bit sick to my stomach. I was probably slightly dehydrated, I decided. I'd been feeling bloated lately, and the extra weight from that isn't good for time. But of course for power it's not a direct factor.

maximal power curve

I was curious how my power compared with historical efforts. Power meters drift, and it's been a long while since I checked my Powertap, so I wouldn't place too much faith in long-term coomparisons. But it was obvious the early pace was higher, relative to my final average, was high. I arguably could have produced a higher final average power with a more measured early pace. But still, I can't complain. My power story was quite competitive with historical data.

I turned and descended Old La Honda Road. Mark Johnson caught and passed me on the descent as I was putting on my jacket. He continued to gain time on me the rest of the descent, I am uncomfortable with the combination of narrow road, many blind corners, and huge uphill cycling traffic tempting upward car drivers to the wrong side of the road. But Mark waited at the bottom, and led me most of the way around the loop. Finally, though, I succumbed to his pace, and cruised back to the office. I was cooked. On Thursday I didn't feel much better, and on Friday I could barely eat. Ah, well... things can't always go well.

Comments

Robert said…
1. Power by duration is interesting but in cases where you're going up the same climb, power by distance is more direct.

2. Do you weigh more or less than you did in 2008?
djconnel said…
My weight has been essentially the same. I did not weigh myself near that ride, but I had been feeling a bit bloated, and that can result in my weight shooting up 3-4 lb. So I strongly suspect I was heavier for this one.

Plotting average power (over time) versus distance is an excellent idea!

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