Using Power Curve to Identify Strengths & Weaknesses

Looking for guidance on how to better interpret and use my power curve to identify things I am good and and those I need to work on.

  • After a nice VO2 block in April and May my 3-5 min power feels really good, I even set an all-time 5-min power PR two weeks ago. But, I wanted to focus on building FTP again as I had neglected that for a good month.

  • I’ve been working on FTP the last couple of weeks and am finding those intervals (15-20 min @ 94-97%) really difficult.

Here’s my curve over the last 42 days.

How long were your longest vo2 intervals (ex 4min, 7min, etc)?

Are you basing your ftp from the eFTP? Mine is way over-estimated based on very high 3 & 5min power. I’d suffer greatly trying to hold that for 15-20min intervals. This might be your issue.

You might also need to just ease into it. When I do a (3wk) ftp block I typically do something like 4x7 min, 3x 12min, 2x20min to get my legs used to pushing the watts before getting into such long intervals.
I also target watts maybe 10-15 below what I think I could test at (20min * 0.95) because these methods are just approximations and it’s better to complete than to fail.

IIRC from podcasts, instead of looking at where you’re weak and fixing that, it’s better to look at what you want to achieve and then building around that.

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I was targeting 3-5 min, and set a 5-min PR on June 27th (412w).

Sorta. Also just overall feel from one workout to another. Regarding eFTP, I tend to think it’s relatively accurate within the margin of power meter error. At least right now. As of today it’s saying my eFTP is 300w, which I think is close to my true 1-hour or Critical Power. Back during my VO2 block it was trending around 324-326w.

I’ve been basing my current FTP session on an FTP of 330w, as I felt it would be higher after the VO2 block and a few really quality long rides. However, I don’t think this is the case. Ok, that’s totally fine, I’ll accept that.

My last 3 FTP sessions (based on an FTP setting of 330w) I’ve been targeting 12-15 min intervals @ 310-320w and they definitely feel hard. I know I wouldn’t be able to hold that (~320w) wattage for longer than 30-min.

I appreciate the advice. I think I need to dial back the intensity closer to ~300w for these FTP intervals.

Taking time off of FTP work always is a shock to the system once getting back into it. My last true FTP session prior to starting this block (2 weeks ago) was back in early April.

Well said, and fair point. That’s kind of what I was getting at.

Here’s my modeled vs actual @ 5-min…I’m in a good spot, and I recently did a 5-min max effort so this is good data:

So, I’ll leave those 3-5 min intervals alone for a bit. Where it gets interesting is at 8-min (granted, I haven’t done 8-min effort(s) in forever, so this data isn’t exactly a great representation, but, 20w under modeled:

Cool, I actually have a once-weekly 8-min (3x8, 4x8, 5x8 progression) workout scheduled to start next week.

Then, looking out to 20-min, my modeled power is not that much higher than actual, again though, I haven’t done a 20-min max-effort above 5-min in forever, so maybe this data isn’t great, but nevertheless:

Coincidentally, I’ve been focusing on workous with intervals in the 12-15 min range around 95% of FTP for the last two weeks. Unfortunately, I haven’t seen any improvement in RPE @ this interval duration and wattage, which I expected to see. :frowning:

More work to do, just need to make a gameplan for what to focus on and how long. Isn’t that always the game plan?

95% of 300W is 285W which coincidentally is what you did for an hour within the past 42 days. Is that close to a maximum effort for 1 hour?

I had the same feeling of high RPE doing threshold after a VO2 max block, even though workouts were scaled to a 60 min FTP test. In the end I put it down to fatigue - the VO2 block felt great at the time -best I’ve felt all year (in January :sleepy:), but it kicked my ass longer term, and had a bit of a downturn. I should’ve taken more than 5 or 6 easy days before ramping back into work. So maybe in your case it could be fatigue too?

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I have done recently second vo2 max block this year. I have seen similar issues to yours, and that’s newt o me and my insights are:

  • Temperature - currently there is 6-9°C more in the place I train, and doing threshold feels horrible even with 3 fans. When I sweat during z2 it means it’s hot.
  • Volume - i have done less volume during vo2 max block due life and it has taken its toll. Currently my observation in wko is that after this year I need minimal amount of volume to perform good during threshold. For comparison my best threshold block was after last vo2 max block when the volume was maintained. Basically after every higher volume block (and I mean around 10% higher) I do perform a lot better during threshold.
  • I have introduced sustained work in form of SST. Done couple of easier 4x20@92, recently 3x30@92%. Every ride felt better than previous one. The other hand in this case is my mental side - doing longer intervals after short vo2 max (4-5) is mentally demanding - one interval is like whole work during vo2 max workout :wink:
  • Like @4ibanez said rest after vo2 max block can be neglected or too short. It is highly individual and you can burry yourself not even knowing.

There is no way to answer your question without you telling us what your goals are. For example, if you are into triathlons and TTs, your sprint power isn’t going to mean anything. For crits, sprint power may be important if sprinting is your jam.

The second question is whether you want to work on your strengths or your weaknesses. Again, I don’t think there is a one-size-fits-all answer here. Usually, one consideration is whether your weaknesses are limiting your performance.

Lastly, you can’t be excellent at everything simultaneously. You can’t be a mountain goat that doubles as a sprinter.

If you tell us what your goals are, I think the people here can give you more specific advice.

You shouldn’t be changing your FTP by +/- 10 %, that’s too much. Also, you should not conflate “hour power” with FTP in the context of indoor training. FTP as it pertains to TrainerRoad is the power that scales your workouts. Holding high power for 1 hour requires special training, both physical and mental, and for many disciplines that is not what you want.

You should base your FTP off of an FTP test. The most common one is a ramp test. Ramp tests measure maximal aerobic power (or MAP for short) and correlate with FTP. However, the relationship between MAP and FTP varies from person to person (I have seen values of 65–85 %). TrainerRoad currently uses a fixed value of 75 %, which is simply the average taken from early studies. But for most people 75 % is off. For me it has been working well, but for many, indeed most, it is off. So you either need to correct your FTP (including lowering it, be honest with yourself). Or you need to use Adaptive Training, which is currently in beta. Adaptive Training is IMHO the better solution and in my two weeks of experience has been working very well.


FWIW, I’ve listened to many Tim Cusick (WKO) videos. The standard model seems to be to extend TTE. Once TTE gets out to say 45 minute then try and raise the roof. Do a few weeks of VO2, retest FTP. If you’ve gone up, great. Now try and extend TTE again at the new FTP.

As far as looking at the power curve, I’m not sure what else you can do with it. You can look at phenotype. Are you a sprinter or time trialist? But, if you have a 1000 watt sprint, you can try working on it but most likely you aren’t going to hit 1600 watts because you are limited by genetics.

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Agree with @OreoCookie , it depends upon what your goals are and what you need to perform.

I haven’t done a true 1 hour effort, but have done a handful of hard group rides up to 2.5 hours. My last big long effort was a 45-min loop. Granted, this wasn’t one continuous effort, but a group ride scenario.

@4ibanez and @jarsson you guys might be onto something, granted, I’ve been good about taking rest as needed. I generally find that poor sleep really impacts performance regardless of how much fatigue has been accumulated. A couple days off should hopefully help.

I wasn’t asking for specific advice, but more for insights on how to read a power duration curve and how it can be utilized to help shore up weaknesses.

Well, the title of the thread is that you want to identify your strengths and weaknesses, and my point is that you can’t tell whether an ability of yours is a strength without having a purpose in mind.

The only thing you can do at this point is look at power charts that tell you where your relative strengths lie. But that only tells you about your abilities, not whether your abilities are actual strengths, that depends on the type of events and riding that you do. Like I said, a strong sprint doesn’t tell you whether you’ll be good at a TT.

Your power is all over the place, I don’t think this will be a good test for maximizing your power over a given time. The best you can do is a single, long, sustained climb. 1-hour climbs are rare in most places, where I live we have one that is 45-50 km away. Even then, I don’t think you’d necessarily pace such a climb at roughly constant power, you’d pace to maximize momentum and ultimately, speed.

It’s a general question, and I posted up my curve as fodder. I wasn’t specifically asking for someone to give me a personal analysis, but more educate me on how to take what information I have (power curve) and use it to identify strengths and weaknesses.

I watched a talk from Hunter Allen, but I didn’t really learn much. Perhaps it’s just as simple as looking where your power lies in relation to the model.

This makes sense.

It’s all I have, but I did do a TTE test in February.

Anyways, was more hoping folks with experience using WKO and or other apps that incorporate the PD curve could chime in with how they use to help with programming blocks of training.

Different tests produce different numbers, and they are usually not comparable. Strictly speaking you should not compare the results of different ramp tests even if they are reliable to quantify your MAP. So e. g. if you do TR’s 20-minute FTP test, the result will likely be different from what you get on a ramp test.

Power tests are most useful if you stick to one and do that repeatedly over a long time. Only that’ll give you a cache of data that tells you how your power has evolved over time. (Of course, you are only measuring one data point, e. g. MAP or a proxy for FTP.) IMHO a comparison between eFTP, FTP obtained from a TTE test and ramp test is almost useless if you don’t have a cache of data and experience.

I would still think you should start from a purpose and choose goals that align with your interests. If you like hill climb TTs and want to maximize your performance, the power chart will tell you whether this aligns with your strengths — or not. Perhaps you want to do them anyway. (I love hill climb TTs even though I am one of the heaviest starters in Japan at 72–74 kg.) Alternatively, you could select an event based on your abilities. In Japan that’d be something like a crit race: I have high absolute power compared with the competition, because most Japanese are significantly lighter than me. If I were in the Netherlands, that’d be very different, I’d be probably one of the smallest and lightest athletes in the field with ok-ish absolute power.

I have been wondering the same thing recently. Incidentally, I think the TR app is a bit weak in this area.

You could try WKO, which will give you specific recommendations based on the shape of the curve (iLevels), but I never found these to be specific enough to be much help. They look something like this screenshot from when i did the 30 day trial (~295 FTP at the time?):


So its telling me my optimal (VO2) intervals are somewhere between 459w for 2 minutes and 308w for 22 minutes… :thinking: I never saw anyone else’s iLevels, so I don’t know if other people got different recommendations, but that seems pretty broad…

Maybe I should go back and compare these to TR VO2 workouts with progression levels…

I’m also interested to know if you have done a ramp test in this period, and if so does it hit your power curve anywhere?

I’d say since this is a stochastic 45min effort your eftp of 300 isn’t far off. Either way basing your sweetspot/threshold intervals off of these longer efforts is more realistic than off a percentage of a shorter effort especially coming off a vo2 block.

IMHO such efforts can only be used to verify a lower bound to your FTP, but should not be used to actually gauge your FTP. But the more varied the effort, the less I think you should read into it, short power bursts can take a lot out of you.

Additionally, there are few segments that are suitable to gauge such long efforts. Even if you have one uninterrupted stretch of road, you might have a short downhill segment where you can’t lay down power (because e. g. it’d be unwise or because you have to break anyway). But more likely than not, you will have to contend with traffic, navigate turns and traffic lights, or stop for water.