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The 40km Project – Part XIV – Now With Power!

This entry is part 14 of 16 in the series The 40km Project

So; the 40km Project has ‘officially’ ended for 2012, as I have no more opportunities to tackle the Calabogie TT course. However, that doesn’t mean I can’t be plotting for the next one, even if it is next summer!

Last Thursday, I found a Kijiji add for a cheap, old used PowerTap. After some emails back and forth, I decided it was worth the gamble. Saturday, bright and early, I headed down to pick it up. I took it for a quick test spin—enough to see that it worked, and then brought it home. It’s an old SL, wired, built into a Mavic Open Pro—great! A perfect fit, given the price :)

I brought it home, and then took it in to the shop—I don’t yet have a cassette lockring tool, so couldn’t get it ready without some outside help. The tire was also pretty shot, so I grabbed a new one while I was there. Tire and cassette installed, I brought it home and mounted it on the TT bike. A minor heart attack as I spun the wheel, saw the ‘transmit’ icon, but no data. Uh oh!

A quick troubleshoot revealed that the CPU was on “bike computer” mode, which means it works like a ‘normal’ computer, using only a wheel magnet. In this setting, it ignores the hub data. I switched it over to Power mode, and everything worked! A major relief!

I went for a quick spin—just an hour—to see some actual data and to make sure everything was installed properly. Since I had decided to test my legs in the Sunday OBC 40km TT on the Heckston course, I wanted to get a bit of a ‘pre-race’ ride in—basically some spinning and a couple of sprints to blow out the legs. Well…that and I wanted to see how high I could pin the power on the new toy!  A couple of hard uphill sprints resulted in me just barely cracking the 1000 watt mark. And obviously for only a very short time. However, I figured it was a nice round number to start!

Sunday was supposed to be rainy. Instead, it was just hot and humid. (Actually, it did rain on some of the riders that started early, and the road was a bit wet in some sections, but mostly it was just hot!) As discussed in my last post, I had decided that a good warmup would be my goal. I had borrowed Shawn’s trainer, and had set it up in the parking lot behind the car. A warm-up game plan scribbled on a scrap of paper spelled out a nice 40 minute routine that I would attempt. The timing worked out well, as I was seeded number 39, which meant I just cut 5 minutes off the first 15 minute spin. I figured this was OK, since I had already been on the trainer for at least 10 minutes before the numbers were handed out.

I finished my warmup with enough time to pop the bike off the trainer, put on my helmet and glasses, take one last washroom stop, and roll to the start line. I was already soaked in sweat—boy it was humid!

I had no idea what to expect of the course, as I hadn’t even driven it beforehand. I just knew it was a straight out and back on virtually dead flat roads. That’s all I needed to know. There was a bit of a headwind for the way out—enough to cause pain!  My goal was to try some of Joe Friel’s pacing advice (discussed last post) and try to keep the first quarter of the race at 3% below max, then the middle half right at my max, then the last quarter, give it everything I had left. I had reviewed my VO2 Max test results Saturday night, and had determined that I wanted to be at 300 watts, which was my Critical Power as of the test. I wasn’t sure how well this would transfer over to a ‘real world’ situation, and also had no idea where I was relative to last year (based on Calabogie TT times, I am below where I was). However, it was the only number I had. Thus I set my first quarter goal at 291 watts, middle half at 300 watts, and final quarter…all I had left.

Starting off, I was immediately going too hard; it really is the natural reaction! I forced myself to ease off, but power was bouncing all over the place—I was having difficulty keeping it steady! However, the first 10km went by quickly, and I was feeling good. This was new to me, and I attribute it directly to the (much) improved warmup. Never again will I miss out on a proper warmup! Rather than warming up on the course, I was already warm and ready to fire!

The second quarter was tough; I tried to pick up the effort. The wind made it hard, but that little number kept urging me on. Just a few more watts Darren.. you can do it! The turn around appeared, and suddenly I had a nice tailwind. Time to relax! Wait… what?  I honestly can say that I didn’t mean to relax (honestly, it’s a TT, no one means to relax!) but apparently my natural reaction when there’s a tailwind is to ease up.. even just a little bit. I realize now that I always do this. And it has hurt me. But not this time. The PowerTap clearly pointed out that I was slacking off, so I picked it up. This thing doesn’t lie! Back up to 300 watts. 320 maybe. Steady. Push. The wind is your friend, but to use it to best advantage, you still need to put out the power!

Sidenote: the ‘back’ leg of Calabogie has always been my nemesis. Shorter, and more downhill, you’d naturally think would be better for me. However, this has proven not to be the case. Now I know why. I’ve been slacking there too. A lot.  Never again though!

Back to Sunday. I kept the pressure on, starting to really suffer with only about 5km remaining, when I started to lose my concentration. However, a quick reality check got me back in the game; the old ‘5km is only as far as from Glen Tay to the pool—you can do that in your sleep’ game. It worked. I crossed the line and popped my computer off the cradle to stop recording. (I was running the PowerTap and the Sigma since HR doesn’t work on the PT, and I also because I wanted to see how close the two were for cadence, speed and distance.)  Tabbing to the ‘time’ screen showed…. 59:12.  Sweet! I was well under the hour!

I rolled a quick cooldown around the industrial park, and back to the car. I quickly toweled off and changed, and Neil had results ready. Of the 42 riders, 12 guys went under the hour! My official time was 59:06. Awesome!

So, what has this all taught me? Well, really, I see three big lessons. One, I already knew but had refused to deal with; a good warmup is key to a good performance. Two; I slack off way too much when there’s a downhill or tailwind. Three; Sometimes pushing a big gear feels powerful, but is really not efficient. Mashing at 80rpm (yes, that’s mashing for me in a TT scenario) vs. shifting down and spinning one gear lower makes a considerable difference. I’m talking 20-30 watts, which is huge.

My average Heart Rate ended up being 180—higher than ever before for a TT. This is after not being able to hold a high HR in a TT at all this year. I think the added motivation of power kept me working rather than slacking.

Oh, so how’d I do at my 300 watt goal? Not bad I’d say–I averaged 296! Seems like the number was about right!

A new version of Golden Cheetah has been release, so I’ll give an in-depth breakdown of the power file from the TT in another post!

Calabogie 2013? Bring it on!

Series NavigationThe 40km Project – Part XIII – The Definition of InsanityThe 40km Project Part XV – Power Analysis


Comment from Sad Panda
Time August 21, 2012 at 12:18 pm

Well done! Now imagine if you were on a bamboo bike. Actually, don’t – I need more bamboo.

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