Power Gurus - Is faster on fewer always better?

In my second year racing with power, I’ve noticed a trend that is both distressing and encouraging - faster bike splits on lower power. My position has changed to a drop of 13 cm vs. about 9-10 last year. Consider the following files, the first from a local sprint, last year then this year.

Entire ride (229w):
Duration: 47:44
Work: 657 kJ
TSS: 80.4 (intensity factor 1.005)
Norm Power: 241
Distance: 18.489 mi
Min Max Avg
Power: 0 579 229 watts
Cadence: 40 141 89 rpm
Speed: 2.4 35.6 23.2 mph
Torque: 0 259 69 lb-in

Entire ride (223w):
Duration: 47:19
Work: 634 kJ
TSS: 74.4 (intensity factor 0.972)
Norm Power: 233
Distance: 18.446 mi
Min Max Avg
Power: 0 466 223 watts
Cadence: 37 131 89 rpm
Speed: 4.2 36.8 23.4 mph
Torque: 0 245 67 lb-in

This one from Memphis in May:

Entire ride (219w):
Duration: 1:00:58
Work: 800 kJ
TSS: 90.7 (intensity factor 0.945)
Norm Power: 227
Distance: 23.421 mi
Min Max Avg
Power: 0 735 219 watts
Heart Rate: 138 162 154 bpm
Cadence: 30 131 89 rpm
Speed: 3 34.1 23.1 mph
Torque: 0 274 64 lb-in

Entire ride (219w):
Duration: 1:00:16
Work: 791 kJ
TSS: 87.5 (intensity factor 0.933)
Norm Power: 224
Distance: 23.362 mi
Min Max Avg
Power: 0 478 219 watts
Heart Rate: 138 169 153 bpm
Cadence: 40 141 87 rpm
Speed: 0 33.9 23.2 mph
Torque: 0 208 63 lb-in

Of course, if I had my druthers, I’d be going much faster on more power. And granted, these changes are small but come when I feel my overall bike fitness has improved over last year. But my question is whether this trend is typical after a position change and whether it’s for the better. And in planning for IMMoo, how does a short course trend like this usually carry over into IM racing?

bump
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I hate to say it, but those differences are so slight, they could be caused by almost anything.

Differences in temperature, wind, etc all can have an effect.

Mostly, you had an identical (or lower) AVG watts, and went a tad (.1-.2 mph) faster, so I guess that’s good. It seems like perhaps your new position is faster than before.

I guess the other part of the equation is - how did you run afterwards?

Maybe the more aero position is compromising your power output. But it is faster, so why worry!

I’d have to agree with MurphysLaw there…the differences in speed and output are fairly small. Passing more or less people, differing wind conditions, temperature affecting power output, etc. All of these can definitely make a difference. Take a look at some of your standard ride courses and you’ll probably find that you have at least a few watts of variation in your average power when you are doing “maxed out” timetrial efforts. Mine are typically 2-3W between trials in the 250-260W range for 1 hr. I’d suggest going over here and reading up on doing field testing:
http://biketechreview.com/phpBB2/viewtopic.php?t=996&sid=1856a6f58a607054c072ab8fa0b7ecdb

Thanks for the replies; I’m sure I’m being over anal. But I hate to see falling power especially when I could have won the local sprint on Saturday with last year’s power and haven’t really seen any power drop in training with the new set-up. I’m swimming a little harder this year and running a bit faster race splits FWIW.

But really more concerned about the big picture of IM racing and whether such a change will really be helpful - my guess is that it will depend on whether I’m able to hold power in a longer ride and stay comfortable. But since my longest ride this year is 47 miles, the jury’s still out ;~).