Power expectations

Hi guys, so I think it would be helpful to know what the expected watts are for a given workout based on our FTP. Just like how it shows the TSS, IF, etc. I think there should be a calculation that gives an expectation for how many watts we can expect to average during a given workout. (edit: should be able to see this before completing the workout)

I tend to have to fish through other users past rides to try and find someone who is close to my FTP to get that estimation and it usually involves a lot of clicking on random accounts and seeing they have an FTP that is +/- 50w from mine

I believe IF * FTP can be use to estimate normalized power of a workout.

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It does show you that. In screenshot below 108 is the average power I did and 104 is what I was expected to do.
image

Yes I’m aware of that, but it doesn’t show you this before you do the workout as an expectation, only after to see how you compared to the target

Yes but NP and AVG W can vary greatly. During one of my more recent workouts the NP was 258 and avg W was 207

How are you planning to use this watt info?

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Just so I can know, wasn’t aware I needed a reason.

I’m not saying that you do, or that you shouldn’t make the request.

However, understanding the planned use case for a request like this is necessary, in order to weigh it against other requests, planned work or active priorities. I suspect that TR needs to see the request in context of your desire and how you plan to use the info, along with their other work so they can determine if it is an appropriate use of their time.

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So as I have read, and I quote “Normalized Power (NP) An estimate of the power that you could have maintained for the same physiological “cost” if your power had been perfectly constant, such as on an ergometer, instead of variable power output”. I don’t really care for estimates, and for context when I ride outside I look at my average power to judge how hard I’m working, not how hard I could have worked. So knowing average power for a given workout is a good comparison to the real world numbers I look at. My FTP is 290 and I’ve had 1:00-1:15hr rides outside where my NP is 300-310w, but average was 250s. To the point someone else made, you can see the info I’m after post-ride, so I think it should be available pre-ride too

@Cleanneon98 The math for NP is as simple as @cjjoefro has defined. So you really don’t need TR to display it on the screen, just do the simple calculation. Since it’s a static number, it probably would not be a good use of screen space.

Depending on your objective with it, there are lots of ways to improve it or lower it. I, for example, believe that TR workouts have too little warm up and cool down (particularly for an older athlete doing sweet spot and above workouts) so I have a few options:

  1. Extend the warmup and/or cool down directly during the workouts (relatively new feature) - lowers NP and IF in real time (you can’t see the effect until after the workout, but its not a big deal for me)
  2. Use Workout Creator to add a warm up and/or cool down (for example, I have cadence ladders that I have built that serve as great portions of warm ups similar to what one would use as part of openers in race preparation) - lowers NP and IF, but you can see the effect during workout creation
  3. Executing a completely standalone warmup (or cool down) as to not effect IF and NP. I have several of them that I use for +1s, +2s, etc. for the sweet spot and above workouts

On the flip side, using workout creator you can create exactly what NP and IF you are targeting. There are a large # of options here that include interval duration, interval intensity and rest interval. I use WC a lot! But not for targeting a specific NP or IF, but rather to achieve Time in Zone (TiZ) goals for the training level I am focusing on (i.e. sweet spot, threshold, over/under lactate clearing).

Again, I’m not looking for workout NP, but Average Power.

For what it’s worth, average power is a poor measuring stick of how hard you are working, and is particularly bad when used to compare 2 different types of rides. For example you might average 200 watts for a steady state effort and also average 200 watts in a crit race where you are constantly surging to 500+ watts and then coasting. The crit race would have a much higher effort reflected by a higher NP and higher TSS. Normalized power is designed to measure physiological effort because average power does a poor job of it (unless it’s a steady state effort). You might consider using NP for both inside and outside if you are trying to compare efforts.

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But in the more surge type rides, you’re doing the 500w+ pulls but then also coasting and soft pedaling, which lets you recover, unlike the steadier state rides. As I understand, an effort is a measure of calories burned or KJ exerted, and aren’t those based on average power overall and not NP? Just trying to understand this as there’s so many acronyms and variables.

@grwoolf makes a really good point, and I’d like to re-emphasize it with the following real world example with #s. I’ll also try to answer your original question now that I understand it:

Last evening I did a ride that lasted 2hrs 45mins. My average power was 124W. As my FTP is 240, using the average power approach you are suggesting, this would be a recovery ride (52%) with a TSS of about 50-60. Correct?

Here’s the real situation: It was a weekly 40 person hill interval suffer fest consisting of 19 Vo2Max hill efforts. My NP for 2:45 including 15 mins warmup and 15mins cool down was 0.89 for an NP of 213 and TSS of 216.

Which approach, AP or NP, do you think better describes the effort?

To answer your question regarding calculating Average Power before the ride:

All of my TR interval workouts that I do indoors I put on spreadsheets. I exclude warmup and cool downs. But I have listed the interval duration, interval intensity and same for rest intervals (intensity and duration). If you did something similar, it would be easy to develop a calculation for the Average Power (mathematically, its a weighted average of the duration and intensity). And if you want to include warm up and/or cool down to the calculations, that would be easy enough to add. As inferred by @grwoolf and my comments, its not clear what usefulness it would be to you, but you could do it.
btw: The reason I put these workouts on a spreadsheet is that I use it for tracking Time in Zone (TiZ) progressive intervals in order to improve fatigue resistance . . . a topic for another discussion.

btw: the place that I have found Average Power IS useful is on a single interval. If, for example, you are doing a 20min hill climb that has a relatively constant grade, you can compare (after the fact) your NP to AP to get get your Variability Index for the climb. It’s a good indicator of how steady a climber you are. When I am really on target I have hit as low as 1.002. For comparison, last night’s overall ride had a VI of 1.74.

One final suggestion: If you are looking for other TR user feedback on Average Power, you may want to consider editing the wording in your top level post to be clear about that.

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If you really want to know the predicted average power before a workout, you can calculate it from the workout description and graph. Just take the power in each interval, including the recovery valleys and the warmup/cooldown, times the length of that interval, add them all up, and divide by the length of the workout.

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There are various ways to get projected power from FTP based on the length of the future ride, here is one calculator but there are others FFT Bonking Risk Calculator [link: fft.tips/bonk] - Google Sheets, works indoors and outdoors.

Co-incidentally I noticed last night that Xert does give the AP for a upcoming workout. Not that I am interested in knowing what it is. TSS is sufficient for me.

You’re pretty much correct. Average power is a measure of energy expenditure or calories (multiply it by 3.6 and by workout duration in hours). Normalised power is an indicator of how hard the workout is. For a steady state effort (TT or triathlon) they’re pretty close to each other, for a group ride or race with a lot of high intensity efforts interspersed with coasting, they can be dramatically different. A workout with AP 200W and NP 250W is going to burn fewer calories but feel harder than a workout with both AP and NP at 225W.

In practice the only time I really look at these on a TR workout is if I’m looking to swap workouts on a plan, in which case IF is key. E.g. if I want to do something of the same duration but a little easier or harder, then I’ll look for a workout of the same type and duration with lower or higher IF. If I’m creating my own workout then IF is a good guide as to whether it’s going to be possible to complete it (if IF is higher than 1 for a 1 hour workout chances are it’s going to be impossible unless your FTP is set too low). But there are so many workouts in the TR library I don’t really bother creating my own anyway!

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