in a TT I know my power threshold. Whenever I i go above this threshold I will fatigue and will pay for it later in the race.

With the PM is can see instantly when i hit the threshold and adjust accordingly. With HR it will take a while before i know I'm at the threshold, can take more then a minute. This will cost you.

Thew same goes for interval training. I know instantly when I hit my power target. I can not do this with HR, the interval could already be over before i adjusted the effort to my HR. And, HR tends to slightly increase when holding a specific power target. If you keep your HR at the same level during a interval, that will result in diminishing power output. And I believe you want to train you leg muscles, and not you heart muscle. So it only seem logical to focus on your power output instead of your HR.

I train indoors through a long cold winter.
A power meter quantifies the gains and motivates me through the winter. I couldn't go back to training indoors without one.

Once the indoor season is over I rarely use the PM as anything other than an analytical tool. I look at the data after a race and see if my perception matched my data - it usually does.

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If you are only interested in training to become more fit, a power meter offers nothing that the HR won't give you. If you want to compare yourself to others, the power meter will provide the numbers so that this comparison can be done. The PM probably has a couple minor benefits too such as quicker responding, more analytics, etc.

Power meters give you a refinement in training for which HR has no equivalent. If you are talking just long and steady rides, then maybe HR can get you close to PM. But for training work with different types of intervals, HR is completely useless.

Of course you don't need one.

Personally my HR numbers aren't as steady as yours so using a PM makes training and racing at the right level for me easier to execute.

jaretj

I'll first say that I don't think EVERYONE needs a power meter. There are two types of people that don't:

- Those that have the ability to ALWAYS be objective with themselves and push themselves further than their mind is telling them without any data confirming what they are doing. These are really rare people IMO. Kienle comes to mind.
- People that just don't have the ability to follow any kind of structured workout or plan. If you can't follow hr guidelines on a run or do intervals/sendoffs in the pool, a power meter will be of no use to these people.


How is your #1 a disadvantage? My wattage has not changed much in 3 years. I recently raised my FTP by 5 watts just so I could try to do the same intervals at a higher wattage. It's not always about having the highest number possible. It's more about holding that power more consistently in your workouts, week in and week out. You are better off consistently hitting power numbers than always trying to reach for high numbers and failing.

#2 is exactly why SOME need a power meter. You are being subjective and saying you should go slower.... why? I'd bet on those days, you would surprise yourself and actually have a good workout and hit your intervals based off power. But you wouldn't know that because too many people are subjective. A power meter takes the subjectivity out of the equation. It's objective whether you are tired, feeling awesome, groggy, got no sleep last night, pissed off, sad, stressed out, etc. It tells you the ACTUAL work you are doing. Your mind and hr can't tell you that objectively.

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How excactly. Using PM indoor makes 100% sense, it's amazing!

But outdoor when i ride, even if i look down on my powermeter and focus 100% on hitting e.g. 200watts the numbers goes like 180 - 190 - 220 - 240- 200 - 190 - 220. Or basically it seems impossible to try and hit a certain value as even the smallest ascent/desecnt/wind change blows the wattage out.

use lap averages to smooth this out. I also use 3 and 10 second averages to monitor my efforts.

I dont need it either, but it is an additional input to help know and understand myself and body better during training. You will for example note how HR will vary depending on your overall stress state and tiredness, not only the effort you putting into your exercise.

In addition is does have motivational aspect in indoor and even outdoor training.

On the flip-side, it costs money, can lead to attempts in breaking your records every ride (specially together with things like Strava) or you trying to hit a specific number in race even if it would be advisable to go harder or easier.

If after all these threads you're not convinced you can't be. I'm pretty sure there's no new argument you haven't seen before.

If you use perceived effort and know your body well, you surly don't need PM, but I'm sure there are more than one way to include power meter in to your training to get extra benefit, but you didn't provide enough info on what your goals are and how you train to give you any info. Power meter is a tool, HR is biological feedback, you need to compare apple to apples.

Windy day, hilly course, indoor, outdoor, hot, cold, power is the only meaningful number I can compare across all of them. My FTP has gone from 180 to 250, HR zones have stayed pretty much the same.

Maybe.
But I still want to improve my biking and maybe I overlook something. So thanks to everyone who reacts here.
And I'm aware of the fact that if I would start to use a PM I would myself maybe find something about it which is useful or just interesting to me and which I never thought of.

That's right, you can quantify exactly how much you improved. I try to do this with speed which works quite well because I always ride the same course. I know temperature and wind influence that but I can make some conclusions which are though, as said, not so accurate as with a PM.
A question remains:
How did you achieve the FTP gain from 180 to 250 W? Do you think you wouldn't have reached that by training for that without a PM ?

After 15 years of bike racing I don't even have a speedometer/computer on a bike. I'm still competitive (for an old fart) in TTs, road racing, and cyclocross. Without tracking my training I seem to enjoy cycling more and train more consistently. If I was going to do anything it would probably be counting hours, or maybe session RPE.

Training FTP is one of the least demanding things you can do with a power meter. Riders have been using wrist watches and a regular training route to pretty good result for a pretty long time.

There are other uses for a power meter that are more demanding but you've probably already figured out ways to do most of them, and you also excluded drag measurement from your list.

Quote:

How did you achieve the FTP gain from 180 to 250 W? Do you think you wouldn't have reached that by training for that without a PM ?

I rode for 3 years with pretty much zero gain. I bought a PM, hopped on TrainerRoad, and put the Sufferfest Four Week Build on repeat. Every four weeks I was up 5-10W.


The PM was a key piece of it but so was a structured training that put me riding 6x weekly. My guess is that attaining the same gains would have been much slower via RPE or HR.

"You can't manage what you don't measure"

HR isn't a measurement it is a reactionary biological response.
Perceived effort is not a measure but a mental opinion.

The other very valuable item is PM measure KJ and that translates into the most accurate expenditure off energy. Having this number allows you to properly plan out nutrition intake so that you're able to keep yourself fueled and ready for the months of training ahead.

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"Train so you have no regrets @ the finish line"

there are days where I'm not entirely there mentally for a workout. i feel like maybe I'm tired, or the motivation is low. this often affects rpe and often hr too.

with a power meter, i can do the workout as prescribed anyways. there's no fudge factor. i've surprised myself by completing intervals on days where i crawled out of bed thinking there was no way i could do it. sure there are days where i just can't do it, but more often than not i end up being able to complete the workout and it's all in my head. without a PM i'm sure i would've either taken it easy or shortened the workout.

like someone else said, if all those threads haven't convinced you, i'm sure nothing we can say now will. my advice is to just try it.

Do you weigh all your food, too? Without an exact count of calories in what good is counting calories out?

Weighing myself every morning is an act of discipline and can be very motivating. In itself, though, it doesn't really make me lose weight.

Training regularly helps. Structured training helps. Measuring training? Unless it's a test or a motivational tool, how would measuring help?

It was just an example of things that haven't been mentioned as a benefit. I realize most people don't go this in depth but for the record, yes I do weigh all my food and liquid consumption daily.

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"Train so you have no regrets @ the finish line"

Yow! That level of discipline is impressive, to be sure. Is your weight pretty consistent year-round as a result?

I have phases to my year because being that disciplined is a bit of an annoyance to the people around me (and wait staff at restaurants). I weigh myself weekly and when I'm not training much (Oct - Jan) I typically just ensure I don't get over 8% above my race pace. If I do I'll crack a whip and have a week or two of clean eating and cut out the crap.

When January 15th hit however it's on! I steadily decline to 3lbs above my optimal race weight and make sure it's very steady and slow. When I've hit low BF% or low weight too quickly I'll then increase my intake so that I'm not just shedding weight week after week. Then when I'm 6-8 weeks out and then I start to shed the final 3 lbs so I hit my target weight.

I've had many years past where I hit my race weight too early and then I got comfortable and let the reigns go a bit and kicked myself in the ass for it. This has helped me derive the best racing weight for myself and also predict what my W/kg will be leading into the key races of the year.

Did I mention I am a bit of a data dweeb and therefore I'm lost without hard data?! LOL

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"Train so you have no regrets @ the finish line"

I don't have a PM but used virtual power as a basis for my winter training the previous two years. Before that, I would use RPE as a basis and that at least kept me in decent bike shape over the winter. But doing focused workouts based on % virtual power was where I saw better gains then just RPE based intervals. I followed written workouts 3x/week and my cycling improved because of it. It was fun to set a virtual FTP, then hit it hard for 7-8 weeks then retest to discover the new higher FTP.