Saturday, July 29, 2006

60 Minute TT

Today we did our club time trial over a 19.8 mile course which is very rolling with 2-3 steep hills. I decided to go for an entire hour since I do not have any exact power data at 1 hour, only speculative data.

The time trial goal was to pace myself using my predicted functional threshold of 293watts. My pacings would be 286w for the first 20 minutes, 293-300w for the second and then let it rip as hard as I could go for the last 20 minutes. Contrary to other time trials on this course, I did not use any aero stuff, just my regular bike that I would take out training or on a ride.

Since it was a rolling course, it was very hard to do these pacings the right way since most climbs would put me well over my pacing limit. So I decided to ignore the pacing goal for the more significant climbs and resume once I was at the top of the hill.

The time trial did not start getting tough until the midway mark where we climb a significant hill on Indian Shoals road. I always have a hard time there and it marks the hardest interval on the course since the most rolling parts are after that climb. By the last 20 minutes I was really uncomfortable and coming into the 19.8 mile mark I was behind my PR time of 51:19. I went past in 52.35 but since my goal was 60 minutes, I gave it my all for the last 8 minutes or so and it got very uncomfortable.

I ended up at 60 minutes with 21.7 miles completed and an average power of 290watts. my predicted threshold from a 20 minute and 5 minute critical power test was 293watts so I was pretty close. I was a little dissapointed since i thought I could go at least 295watts for the duration. I think my goal of 320watts by late October is going to be too hard to accomplish but we will see.

The graph below shows the wattage pattern for the entire time trial (Figure 1)

The next figure is the quadrant analysis of the time trial and you can see that a lot of my efforts were done below my threshold power. Most of this is because it was a very rolling course and there were a lot of hills. On a trainer I would suspect that all of the dots would be at or above my threshold. Also, with the pacing I did, at least 20 minutes or so was supposed to be below threshold. I did not want to start out too hard and then fade.

The next figure shows my 20 minute interval power numbers as a judge of my pacing. It is pretty clear that my pacing was not good and you can plainly see my power dropping from the start to about 40 minutes. From 40-50 minutes is where the numerour rolling hills kick in and I cut it loose trying to get up those hills with high watts. The last 10 minutes are mostly downhill or flat with one hill near the end. The good thing is that I was able to still keep the same power wattage for the last 8 minutes that I had done all ride, the bad part is that this is where I was supposed to cranking it out and finishing strong. I was expecting myself to finish the last 5 minutes with around a 300w average and this simply did not happen.

Conclusions to draw from this? I was happy to do the 60 minute effort since it was my first. Clearly the course presents me with large challenges in terms of pacing and being efficient. I speculate that things would be different on a flat course. While 291watts is lower that I had hoped for, it is close to my predicted threshold value and hopefully I can move forward from there as i do more time trail efforts in the next 8 weeks.

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