Target power vs reported power

General Site Questions
#1

I use a crank-based power meter and kicker core trainer with TD and custom erg mode workouts. Since I ride indoors way more than outdoors, I usually leave the same bike on the trainer all the time and ride a different bike when I go out to ride. Unlike the kicker, my power meter is auto-calibrating (quark).

Since I don’t use power smoothing the reported power moves around a lot. In fact, I don’t constantly watch how the workout is going, I just check in from time to time and look at the results at the end. Sometimes the workout seems really easy and I’ll check the app to see what’s going on and the target power will be much higher than the peak reported power.
If I stop the workout and do a spin-down for the trainer everything seems to go back to normal.

Since the app is getting power from the power meter and controlling the trainer why am I still having to do spin-downs? I love the app and think it’s a great value, just wondering.

#2

Are you using the power match feature? In the settings? If so and your kickr power is not too far off from what it should be and you are doing more endurance type of workouts then power match should solve this problem. If you are doing high intensity short duration intervals our power match works better on some devices then others.

#3

I am using power match in the settings. I can really notice the issue when riding at a steady state and at my age, I wish I could put out big numbers for any duration. As I said it is infrequent and a spin-down calibration in the wahoo app fixes it until the next time it happens. I guess what’s strange to me is that it doesn’t seem to be a gradual shift but more of a one-ride to the next change. It may be something inherent to the trainer if TD is simply inputting target power to the trainer and the trainer responds as it may. I had hoped that maybe the app monitored and adjusted as needed for symmetry. An occasional spin-down is not a big deal. I can notice the problem right away, I just prefer to warm up the trainer before doing it. I guess my power meter is really not making the ride power more accurate than just using the trainer’s reported power but I guess It does let me know if I need to do a spin-down calibration.

#4

If you are using power match then you can verify it is working correctly and you are following the correct power if they power line basically matches the blue chart bars. If it does then that is all good and more accurate than your trainer (for most power meters, I assume yours) so you could send a screenshot while you are doing a workout but it sounds fine and seems like the spin down is not necessary but still not a bad idea to do it periodically anyway.

So to clarify with power match on it does monitor the difference between your trainer and power meter and adjusts the trainer to match the power meter.

#5

OK, I’m a little confused. The power line is a sawtooth and just looking at the bar, you have to guess where the average is. The reported power number also fluctuates quite a bit depending on smoothing. If the workout becomes too hard or too easy over time (workout to workout) I can either adjust with the offset buttons or make a new workout. I’m not a number geek, I just want consistency so I can monitor how I’m progressing, if at all (hey, I’m old, really old). If everything feels as expected during the workout then I mainly look at the average power and heart rate in the ride summary to gauge how I’m doing.

If the app does adjust the trainer to match the power meter, that’s great but there are occasions when reported power is maybe 20% lower than the target. I feel like a hero until I look at it and see the powerline is well below the target bar and it’s time to do a spin-down calibration.

Maybe at those times, the trainer is so far off, the app can’t compensate. At any rate, I have no real complaints. My needs are simple, If I could create workouts in Wahoo’s app I would be using that but thankfully this app exists and here I am.

#6

We love old, and really old :slight_smile: I am 57 but already trying to plan for 80 :slight_smile: Yes power meters due to the way people pedal are very jumpy lines you can try to use our smoothing feature to reduce the jumpy lines. You also can also click on the HR field or power field (not 100% sure), I can’t remember… but it will show average interval watts.

Anyway yes, the way our power match works is it waits about 20 seconds to determine if it needs to make an adjustment to the power to get back on track. This is the nature of power match to some degree. Power match is complex so we could reduce this 20 seconds but it’s not easy.

Glad you are happy :slight_smile: