Psimet2001 

We're over 10 years into the power wars and people still don't get the basics.

1. Your peloton is wrong.

2. Even though I own stock in Peloton - who cares if it's wrong?

3. Getting 2 power meters to be the same is a worthless endeavor with absolutely no return.

4. "FTP" - as a concept - will be different for each rider when they are indoors or outdoors. NP aside. Usually the outside FTP is higher than inside. Does it really mean that the body performs differently? No... just the way it is. Research it if you're super interested in actually knowing why.

5. Please take the time to read, understand and commit this next part to the core of your philosophy regarding power. Power, the way we use it for cycling, is simply a number that exists to allow us to know certain things about our training, ability to produce work, fatigue, etc. It is not a measuring stick to be used outside of the world it lives in. It is meaningless without the context of you and the activity and specific device. It exists solely to help you understand and plan your training. If you are not using it to plan and conduct your training then you are in fact just using it as a measuring stick. Using it solely as a measuring stick will set you up for disappointment and burn out. Your body's ability to product power while riding will change over time. It is NOT a continuous journey upwards either. It will ebb and flow with all sorts of other factors. I have watched scores of athletes freak out when the needle moves backwards even though they are "doing everything right" instead of simply accepting that it means they need to adjust their workouts now that their fitness is changing.

6. Those that say the accuracy is more important than a power meter's precision - incorrect. We have actual market data that proves this point. Computrainer and Velotron were both way more accurate than any other device out there. They still work with Zwift, trainer road, etc. The training hasn't changed. People will willingly pick a less accurate power meter because of other factors they feel outweigh accuracy. Example 2 - Verve Cycling's "Infocrank". This was a testing company that was hired to do accuracy studies on power meters. In the process of testing them they realized that almost no one making a power meter really know what they were doing in terms of accuracy so they went out and designed their own. It was way more accurate than just about any other commercially available powermeter. Their price point was $1500 or $1800. The selling point was its accuracy. I couldn't sell one to anyone. "It's more accurate" was met with "I don't care. It's too expensive and as long as I use the one I have for everything and it's consistent then it doesn't matter what the actual specific number is." That company is now lost as a footnote to the world of cycling. Accuracy doesn't sell. Precision (repeatability) is the cornerstone of the power market.

7. I ran a computrainer multi-Rider studio for the better part of 10 years. I would have riders on computrainers who were riding with their own power meters pretty much since day one. I would watch the riders get ticked off because their numbers from their meter wouldn't match with the computrainer. I'd then watch them ride the same computrainer (sometimes for years) and continue to get roughly the same numbers. Their own power meter would be off. They would calibrate it, send it out, etc. Eventually they would move on to the next one and low and behold it was in agreement with the computrainer. So many times a rider would yell until they were red int he face that there was something wrong with "my" equipment only to eventually find out their stuff was bunk. I could almost always put a couple of different power meters across the same trainer and get the same power numbers averaged out across the board all within their tolerance of power readings. (3% max on a computrainer and like 5% on a quarq could end up in a legitimate ~20W difference in values at a 260W effort and still be where they were supposed to be.

What that whole process taught me was that - power meters are really just like massive placebos. They just aren't accurate in general. If you use the same one all the time you can use them effectively. If you get worked up over one giving different numbers then you're kind of missing the point. When people have them they feel great. Regardless of whether they actually improve someones training (like giving someone a nice car won't improve their driving but they like having a nice car). People without them have massive FOMO. Then when they have them they create an expectation on specific numbers, when they can't get those numbers anymore then the world collapses in around them. Many leave.

So....advice (even when it wasn't asked for) - If you aren't going to use the data from your power meter to lay out and control your training, racing, or recovery then do yourself a favor and just don't use one. You will still love riding and "training" just as much and maybe more.

asgelle

What about informing equipment choices or controlling caloric intake (among other legitimate uses)?

tomato coupe

Yep, my power meter keeps telling me to get a red bike and to quit eating donuts.

kosmo886

Does seem the 260w is not happening, just didn’t think a 200w avg. got to 20mph, which is what my rides typically are +/- if I’m solo. In my case, I have always been slower in a group just given pacing, which has always been slower than any aero benefits. That said, I also haven’t found a group of stronger riders yet. Given I am new to this, I’d probably kill someone in a proper pace line anyways!

WhyFi

My power meter says that I've burned enough calories that I can enjoy a donut (or six) as a reward.

Psimet2001 

Equipment choices? That's a stretch. If it has to do with "efficiency" (aerodynamic or otherwise) of a piece of equipment then I would hope that would be because of a race or competition. If that's the case then it is training - refining the ability to produce power as needed for the application of racing.

Controlling caloric intake? That's training. If someone has a specific health issue they need exacting caloric data for outside of simply trying to lose weight to get faster then sure. Using it for losing weight to get faster - that's training.

We can play the semantics game all day. The point is that most people get a pm because they think they should have one. They don't really use the information from it for any other purpose other than to say things like, "oooo that was a hard ride" and "Oh yeah? Well I can average ___W. Is that good?"

If that's really going to be the extent of their usage then HR would be a better indicator as it's way more neutral than power. People just understand that their heart can only go within a range and they typically don't try and measure up their HR next to anyone else's. It's an adequate indicator of how "hard" they went and can be an indicator of progress of fitness, being sick, needing recovery, etc.

After seeing the passion for life just simply vanish from rider's eyes while they're in the midst of 6 months of extremely specific power driven training.... I tend not to hold it up for any use other than for specific targeted competition. After having watched a ton of riders improve greatly without the use of power it just isn't needed at the entry or lower levels of the sport.

Honestly I don't care if someone has one. I'm not gatekeeping power. I just warn against it's use at the recreational level because the understanding of it is usually very low and it can serve to de-motivate way more often than it can serve as a motivator.

asgelle

Talk about semantic games. Equipment choice has nothing to do with producing power, just the opposite. It's about maximizing performance for the limited amount of power one can produce.
You don't think it's possible that someone would want to control their weight without a specific health issue? But at least you acknowledge a legitimate use for power meters outside of training (in the most common use of the word).
You're certainly entitled to your opinion. That doesn't mean others can't consider other uses equally valuable.

colnago62

here is some power data from some warmup laps at the velodrome. Power was taken from an SRM Origin track crank.



there are several laps that are in the 20mph range. Notice the power readings. My guess is wind was minimal. July in general this year had very little wind at the velodrome. On the road the numbers might be slightly higher due to the difference in riding position and equipment, but not by a huge margin.

Psimet2001 

This is actually incorrect. We often select the best compromise between power that can be produced in a position vs the aerodynamic efficiency of that position. Different saddle, bars, positions can greatly impact or limit the power that we are able to produce but sometimes the trade-off results in a net gain. Sometimes we will change a piece of equipment to allow the rider to produce more power in an already compromised position.

Many riders would benefit more/get faster and produce more power from a proper bit fit than by using a power meter.

drewtk

Psimet2001: Regarding accuracy and repeatability of a power meter, I agree with you, and unfortunately it’s a concept that many do not understand. In a perfect world, I want a power meter that is both accurate and consistent with itself (repeatability). However, if I had to choose, I’ll take the repeatability so that I can have consistency with my training. I don’t really care about my power numbers vs others because ultimately I’m chasing performance.

The discussion above about the power to hold 20 mph, assuming flat and no wind, is pretty interesting. Again, I realize power meters are not always accurate, but I’m surprised by the result above showing 200 NP watts to hold 20 mph. I would think that 200 watts would result in more than that. Many variables I’m sure.

On my next ride, I’m going to see how many watts it takes for me to hold 20 mph, on the hoods and in the drops.

rubiksoval

I think it's a concept that people who care about training with power understand perfectly well, and it's a factor when talking about power meter usage. Most people aren't going to use the same power meter forever. When you change powermeters, the accuracy of both your former and your current meter do actually matter to a lot of people.

I don't train using the built in powermeter of my Tacx Flux, not because it isn't consistent, but because it's consistently 10% less than my other powermeters.

You and he may not think accuracy is more important than consistency, but that wasn't the initial assertion in the first place. The initial assertion was that "experts" say consistency is more important.

No, they don't. I don't think many people who actually train with power would think that, either.

And no, you really don't have to choose.

Pizzaiolo Americano 

Why would accuracy trump consistency? It would seem like consistency day to day would be paramount if one is trying to improve or pace themselves to keep from blowing up (the only reason I really use mine). I am a MTBer for the most part so maybe it is different? Don't take this as arguing your point. I don't know enough about this subject to form an argument...

rubiksoval

It doesn't. They're both equally important.

A powermeter that consistently tells you you're putting out 500 watts is just as rubbish as one telling you you're consistently putting out 50 watts.

MoAlpha

I have to consider myself low-level and all I'm training for these for days is a crummy, informal, unsanctioned, TT series, but at age 64, the old desire to push the training load and the real danger of exceeding one's diminished recovery capacity, makes a PM–and an accurate one!—pretty useful. I used HR for running for many years and it was a great tool. On the bike it was much better than nothing, but it consistently underestimates my load because once I'm in shape, my HR doesn't catch up on the continuous series of short climbs that make up any ride around here.

As for wattage pissing contests, forget it. I am a 140 lb weakling and my computer is set to display only zones. Anything over 300 is just Zone 7 point something.

Pizzaiolo Americano 

Why does the actual number matter if the reading is consistent? The only thing I could thing would be if I had more than one and was swapping back and forth. Unfortunately, that isn't the case for me...

MoAlpha

For the same reason that the apparatus used to measure out the 500 mg dose of acetaminophen in your Extra Strength Tylenol needs to be accurate. Training stress is like a drug with a therapeutic window, below which it is ineffective and above which it is toxic. There's individual variability, but if you want a dose near the top of the window, it's nice to be calibrated.

Pizzaiolo Americano 

As long as I am dispensing the dose needed using the same measure each time, I am not sure how that would matter? It is not as simple as a certain height, weight and age needs to train to a certain power. That believe that is, however, how they configure initial dosages of meds. Again, I am not saying anyone is wrong because I don't know anything about this. I am just not following this particular reasoning.

kosmo886

very interesting. thanks for sharing.

MoAlpha

Good question. Exercise will not wipe out your liver or leave you in pain like acetaminophen, so the downside to being wrong is pretty mild, but as with Tylenol, there are still pretty good empirically derived models for the relationship of specific dosages (wattage relative to benchmarks like your FTP) of training stress to performance, which are a good place to start. You could construct the whole model yourself by gathering lots of noisy performance data at every exercise "dosage" and finding the optimum, but that might take a lifetime. It's much simpler to use received wisdom and vary how you use it based on experience. Make sense?

Pizzaiolo Americano 

Would doing an FTP test to get your starting zones not be effective? I can't see how any formula would get as close as that. I've spent the majority of my life in the military (recently retired). We took semi annual fitness tests. The results among people of the same age groups varied wildly. I would routinely have young, very fit looking subordinates do poorly or fail these tests while my less fit looking folks would do awesome (and vice-versus). There is no way I could judge their actual fitness level without taking them out several times a week and watching for myself to establish a base line. From there, I could help them prepare based on their individual levels in specific components. There isn't a formula in the world that could have accounted for that. People are too different.

rubiksoval

Sure. That, and what happens when you get a new one? You won't have the same powermeter forever, right? If they differ, what are you going to do with either your old or new data? Just toss it? Start from scratch?

What about zwift? Ever get on that? Your results are completely dependent on your powemeter (for better or worse).

And then there's performance analysis, if that's something your'e concerned with. If I'm targeting KOMs, and I reckon it's going to take a specific w/kg to achieve a time goal, but my powermeter heinously over or underreports wattage, no point in even monitoring power.

rubiksoval

What's your definition of FTP?

How would you go about testing that?

The above two questions cause WAY more issues than accuracy vs. consistency.

jadocs

That's a very respectable solo pace....You should be happy with that result.

MoAlpha

You mean with an inaccurate, but precise, PM? I am not an engineer, but I would say as long as the error was just a constant offset over the operating range, yes. However, in my experience instrument errors, (when they're even linear) are usually multipliers rather than simple offsets.

Ah, I see what you mean now. Yes, some sort of personal benchmarking is how the whole thing works.

Pizzaiolo Americano 

Those points all make sense.