Functional Threshold Power (FTP) Test

Finally...Power!  I had long decided that a crank-based meter was the right call for me as I already have three rear wheels.  I settled on a Quarq since they are cheaper than SRM - and don't have the battery issues (have to send the device to Germany for replacement) - and have a model specifically made for Specialized cranks.  I had been intrigued by the possibility of the upcoming Vector (now a Garmin venture, slated for release in 2012), but I didn't want to wait.  Juan, a mechanic at my sponsor shop, Hi-Tech Bikes, recommended it and I know several others that have one.  I just wish I would have made the decision a little earlier, so that I would have had it in time for Ironman Louisville (it arrived the day before I was leaving, not allowing enough time to get it installed).


Anyway...I got the device installed as soon as I got back from Kentucky (thank you Matt at BMB!) and used it on my first ride - a hilly 50-miler through Del Dios and Elfin Forest with the Tri Club.  I was surprised that my average power for the 2½ hours was about 230 or something.  Definitely more than I have been able to sustain on the CompuTrainer for the same length of time.  I'm curious to see how the wattages relate.  I'm sure there are differences as the Quarq ignores coasting and there's no coasting on the CT - just consistent pedal to the metal (ouch).

Following that first ride with power (and a 60-miler on Labor Day on my roadie), I set out to do my first Functional Threshold Power (FTP) test on Fiesta Island.  With some help from my buddy Jon Davis, I put together a workout and headed to the Island after work.  There are varying schools of thought as to how to formulate the workout, but basically, the idea is to record the average power for a 20-minute all-out effort and take 95% to determine FTP.

It is recommended to warmup as you would for a time trial before starting the test.
Here's what I did:

20 minutes @ endurance pace (~130 bpm)
3 sets of 1 minute all-out efforts, followed by 1 minute of soft pedaling
5 minutes all out
5 minutes easy
20 minute test
12 minute warmdown

Ultimately, the reasoning behind using power is to temper workouts and race efforts (especially in the beginning) to avoid going out too hard and fading down the stretch.  As a triathlete, it's important that I'm able to run off the bike and I have yet to figure out how to do that successfully - at least not in long distance events.  The general consensus seems to be to manage your effort on the bike, keeping your power output as even as possible - not spiking on hills - and save something for the run.  In the race environment, it can be difficult to tell how much wattage you're putting out early and it can be easy to fall in the trap of racing anyone that rides on by.  There are some general formulas / guidelines to help determine consistent power output for various race distances.  These are the percentages of FTP that Jon sent me:

Sprint: 100-103%
Olympic: 95-100%
Half-Iron: 80-85%
Iron: 68-78%
Dbl Iron (?!): 56-70%

So...what does this all mean for me?  With an average output of 314 watts for the 20-minute test, my FTP (95%) is about 298 W.  So for my next event, a sprint (Mission Bay on 10/2), I should basically try to keep things just a little lower than all-out effort - I'll shoot for an even 300 W.  That's about what I would have been trying to do anyway, but now I'll have a way to measure the power so I don't go out at 400 W (my 1-minute threshold power) and fade through the remainder of the bike.  Maybe keeping the bike even will help me on the run, too.  I'd like to break 19 minutes for the 5k.

Now if I can just do something about that swim...