Sunday, April 23, 2006

A new Functional Threshold

For the first time in forever, I was able to get outside and ride with a group of friends this weekend. The task was to get in a solid 3 to 4 hours of riding. My longest ride to date this season has been a single 1.5 hour trainer ride months ago. Otherwise, I've been living with 30-45 minute trainer rides all winter. Afterwards, I realized that my indoor threshold figures are no longer valid as the ride moved my Mean Max Normalized Power curve up another notch.

You can see, the highlighted area estimates my new FT somewhere near 330-335 watts. Seeing as this wasn't a formal test, I need to use other means in determining the correct figure.

To justify the need of changing my threshold (and thus my zones), I took a quick look at the distribution of both my Heart Rate and Power in relation to my training zones. I'll spare you the pictures, but the power zone distribution clearly showed lots of efforts higher than their corresponding heart rate zones. Thus, my power zones are understated.

Lastly, the ride itself scored a TSS of 297 with an IF of .908. The ride was tough. But, it felt more like a .8 IF. 275 watts * .9 / .8 = ~310 watts

Clearly, I have evidence enough to adjust my threshold settings from 310 to 335. So, split the difference until I can test further. (335+310)/2 = ~320 watts

Now, if I can only drag myself to the pool, I might have a chance at a decent showing next month in Effingham.