Bike Functional Threshold Power (FTP): 270-280 Watts

Trying to fit in my bike test this week was a bit of a challenge…particularly since I also wanted to get in a running test, and be back at normal training volume for the weekend.

…and I also will be increasing the calories/carbs quite a bit this week so that the tanks will be full for the maximal testing…hopefully not _too_ fat by Friday

Rain, heat and high humidity forecast for the beginning of the week…Monday a total rain washout, would have been the best day for the bike test, so did my test on Tuesday…between lines of storms…hot…humid…not ‘ideal’…and did ride back in the pouring rain, but dry for the test

…I don’t like riding in the rain, not because you get wet…blind drivers, behind streaky windshields just add to the open road hazards…oh and then cleaning the bike after…more time overhead…

…Wednesday was forecast to be cool and dry, but if I wanted to do my run test on Thursday, I needed to get the bike test out of the way, leave an easy day on Wednesday…2 days between the 2 tests would have been better…and then a day on Friday before ramping back up the big bike on Saturday, with a planned 2nd ride on Sunday…always conscious of the impact on workouts on downstream training…and oh…I need to fit in a 3,000 yard swim session…most likely on Friday…hopefully my legs won’t be too cooked from the run test on Thursday…

So I just got it done…results about the same as my last test…maybe a bit higher factoring in the heat and humidity…in either event, the demons in my head worried about shriveled muscles, quieted for the moment 🙂

My last bike test was on May 3, 2011…cooler, 72F, and not quite as humid 61%, and windy 15-30MPH…the results from that post:

  • first half southbound: 270 Watts (146HR avg, 152HR max)
  • second half northbound: 271 Watts (149HR avg, 152HR max)

I called it 270W for training calculations. (Endurance Nation Test protocol: 267 Watts normalized power for 42 minutes: 20 min HARD/2 min easy/20 min HARD)

So on Tuesday, Sept. 6, 2011…same course, same test, hot by the time I was able to get out just after the last morning downpour, and before the next one: 82-85F, humid 74% (at least), and windy 15-20MPH

  • first half southbound: 269 Watts (144HR avg, 149HR max)
  • second half northbound: 267 Watts (147HR avg, 152HR max)
  • (Endurance Nation Test protocol: 265 Watts normalized power for 42 minutes: 20 min HARD/2 min easy/20 min HARD)

Interesting result…within a couple of watts of power from my earlier result on a day that was 10F+ hotter and more humid…my power did fade a bit in the last 10 minutes of the test, even though my Heart Rate was pegged at 152HR, so probably an indicator of the heat and humidity getting to my body regulator trying to get serious about some more cooling

…and I was probably a bit conservative in the first leg…so didn’t get ‘all of it’

…although, it was a lovely, tough workout 🙂

The impact of heat on power on the bike is not as well documented as the run…nor is there a general agreement on the impact…too many variables on the bike…of the reading that I’ve done, I think that a 5% decline in power between a ‘cool’ and ‘hot’ day is a reasonable ‘median’ number to use…although what constitutes either is also a matter of debate.

So on a cooler day, this tells me that I would probably be in the 270-280 Watt range on the same course…the hills and the wind also reduce test scores, so an argument could be made that with the same effort, on the flatter Ironman Florida course, on a cooler day with less wind, that I could turn in a 285 Watt test…maybe.

Where all this is important, is to help me gauge my training power goals as accurately as possible over the next 4 weeks, as I shift to more specific bike training for Ironman…so less on high end power, and more race specific power.

And race specific power is calculated as a percentage of my FTP … Ironman race power for age group triathlete’s ideally between 68-78% of FTP according to Allen & Coggan…and quite a few others quote roughly the same range… depending on how much you want to bite off on the bike, and how much you want to leave for the run…more on that race balance as we get closer

…but the same applies to training…on my race simulation days coming up, I want to be as close as possible, so 68-78% of FTP, which is a high Zone 2 Intensity:

  • 270 FTP: = 184 – 210 Watts > 70% = 189 Watts
  • 280 FTP: = 190 – 218 Watts > 70% = 196 Watts
  • 285 FTP: = 194 – 222 Watts > 70% = 200 Watts

Cross checking this against a recent workout, my 3 hour ride last Saturday, I did 3 sets of intervals on the same route as the test, each interval ending up in a high Zone 2 Heart Rate:

  • 202 Watts: 127 Heart Rate max
  • 209 Watts: 130 Heart Rate max
  • 206 Watts: 133 Heart Rate max

So this tells me, that on that route, using a 280 Watt FTP, and 70-75%, 196-210 Watts for race simulation is about right…may be a _hair_ high, so I’ll need to watch it…and cut it back a bit on hot/humid days…as I did last Saturday, a shade over 200 Watts sounds like a nice even target for Z2 race simulation riding.

…and my Z4-5 Hard Intervals, 95-100% of FTP, really need to be up in the 270-280 Watt range, so need to do those either early when it’s cool, or inside on the trainer before I go out to be able to get the full power in without a heat/humidity fade

…my ‘official’ bike training zones, based on a 270 FTP

Bike Zones
Zone HR Power
Z1 / < 70%:
< 123
< 188
Z2 / 70-75%:
Z3 / 80-85%:
Z4 / 95-100%:
Z5 / > 110%:
> 145
> 297

As the training shifts to more time closer to race specific power, there can also be a tendency to lose some of that high end maximal FTP power…since I won’t be training specifically for it…although I should be stronger and longer in the race specific zones, and what is steady riding now at 70% of FTP, _should_ become the same effort at 75% of FTP …so it sort of washes out

For Ironman Florida, I’ll most likely target 70% of my FTP, to leave more legs on the run…the run will be my key focus…and therefore, I may even shift my race goal power down towards 68% based on my final numbers in October, particularly if my run is looking strong.

…of course, if your eyes glaze over when you read this, it means that you don’t have a Power Meter, and live a simpler life 🙂

…suffice to say, that Ironman race pace on the bike is about 70% of the maximum effort…Zone 2’ish Intensity…check out the chart as a reminder on Zones…that you could put out in 1 hour…so sort of the same with Heart Rate, as a percentage of your average Heart Rate for the same maximal test…more variables in Heart Rate than Power, but the same idea

…don’t cook your legs on the bike

…coming off the bike fueled, hydrated, happy, with a good steady ride sets up the best run times

…and a steady, but easy first 6 miles on the run, at 30 seconds per mile slower than your target time, helps a lot in not losing a pile of time in the last 6+ miles when a lot of ‘runner’s turn into ‘zombies’, losing 5 minutes+ a mile on dead legs

…been there…no fun

…note to self…don’t do it again 🙂

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