Power is not definitive, it is a factor, the same as HR

The Podcasts and details along side the workouts and plans seem not to agree with the view of a number of respondents here that W and HR and perhaps RPE should be used in conjunction, the podcast etc seem to maintain the absolute authority of power.

Whilst N watts will always move 1 kg the same S distance along a frictionless surface; when it comes to training benefit 100w, 200w 300w may have a different affect at different cadences, probably at different times too, and probably reflecting different motivational states of the athlete.

Okay perhaps I jumped the gun, “should” is a matter of opinion as it is almost an instruction. “Could” would be more accurate in the TR philosophy.

You can choose to record your RPE and HR if you want, but it’s not necessary to use and reap the rewards of TR plans.

By the way @stevemz I thought power was Newtonian physics not thermodynamics. Am I right?
w=FxD

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Energy being neither created nor destroyed, only transformed is what I was referencing.

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I’ve heard Chad reference multiple times that when doing a time trial, RPE takes precedence over power.

TBH, that’s common sense - as if you stick religiously to a power target, you may underperform - either because the power is too high for how you are feeling that day and you blow up, or because you are feeling differentially strong and could have gone faster.

I think for training, same is true. Great to have a power target to aim for, but be willing to adjust on the day depending on how you are feeling. And maybe even change the entire workout.

Power is ‘rate of change of energy’. You can discuss power in the context of Thermal Energy just as you would any other context. It’s complicated in thermodynamics because generally they are discussing ‘closed systems’ and are primarily concerned with the energy rebalancing itself within that system, so they don’t discuss ‘wattage’ as much. Work may be what you are thinking of, which doesn’t care about the duration with which the force was applied. Only that the energy (potential, kinetic, etc.) at time t_0 + t is different than the energy at t_0.

The definition of ‘work’ annoyed me when I was learning it.

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In my opinion, you have thought so long and hard on this that you aren’t even sure what you are trying to solve by coming up with an alternate idea on a topic you might not have that firm a grasp of. You think you are trying to see the forest from the trees but it appears that instead you’re micro-examining things further.

Anyone into photography knows a person who spends hours upon hours deciding which lens to purchase and loses track of why they even want the lens in the first place. I think you’re in this place.

Later in the thread you say a person should consider heart rate too. Virtually everyone already does this.

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Don’t you mean “Output”

And “Total Output”

:rofl:

https://support.onepeloton.com/hc/en-150/articles/203325985-Understanding-Your-Metrics

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You sure it’s not the other way around?

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I’m a little disappointed this thread has devolved into what one might arguably call a meta-physics argument. :rofl:

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Use HR potentially to determine if something is off (to keep it really simple).

Let’s say my FTP is 270. Let’s assume for the sake of argument that if I’m doing a long endurance ride I’m aiming to hold very roughly 190W. I am personally expecting my HR to sit somewhere in the low 140s.

If I’m early in the ride and its 155, that should signpost to me that something is up. I could be tired, dehydrated, coming down with a virus, etc etc; I might use that info to decide to bin today’s workout and sit on the couch instead.

Similarly, if I’m doing SS intervals, I’m expecting a HR in the low 160s. If I feel good, am hitting power, and it’s 155, that might be a sign I’m getting fitter. On the other hand, if I just can’t get my HR up, and I feel tired, and it’s a struggle, that might be my body’s way of saying I’m tired and need a break.

So I will use power to set my training, then use HR to tell me that all is well (or not). So HR is ‘a factor’, but it should come after power, if that makes sense.

Edit: I’ve just looked into my Training Peaks data. The ride the day I came down with Covid shows me averaging 10-11 bpm above my normal!

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Well, now you have me wondering if actual diesel engines ever have days when they’re just not feeling it!

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I think speculating at what I’m saying then associating it with someone who loses track is to be frank insulting. Especially when your final quote used to prove your argument is exactly what I’m saying. HR is important too and should be considered

I don’t have a ton to add to the science, but I do have a lot of personal data to look at on long boring trainer rides and this is really interesting to me. I guess in general, I look at power as a measure of how hard my muscles are working and heart rate as how hard my aerobic system is working. So if I’m trying to do a workout that’s focusing entirely on aerobic response, my primary metric is heart rate (which is to say I hold that fixed and look at how power varies with respect to it). If I’m working on anything else (be it high intensity, or even just muscle endurance) I hold power, and look at how heart rate varies. I also change up my cadence a lot (unless I’m doing a cadence-specific workout) because I get bored easily, which also has the added benefit(?) of getting my body used to varying cadence. Last time I did tempo intervals, over four intervals I tried cadence varying from 85 to 105 RPM, and was within 1W for the same HR at all cadence ranges - so I think there is some level of adaptation there as well.

One thing I think is really interesting is looking back at my endurance rides over the course of a block, season, and year. I always do endurance rides by HR, and then only look at the power after. Over time, I can watch the power slowly creep up even though HR stays the same, and to me that’s a really tangible way to see base aerobic capacity increase. I think it’s really cool.

Again, no science here. Just my own observations based on my own riding. But maybe it resonates a bit with someone else.

You have made at least 3 claims re: HR in this thread, all with different qualifications; it is “important”, it should be “considered” and it is the “same as HR.”

Whether it is “important” is open to discussion and depends on how you determine “importance”. Almost everyone would agree that it should be “considered” at some point. Saying it is the “same as HR” as a metric is just simply incorrect.

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IMO, doing endurance rides by HR is arguably the one area where training by HR can be beneficial. Your power range for endurance is pretty large, whereas you can work on a smaller range on HR to stay more consistent.

But you can still see the same training effect as noted above, but in reverse if you still choose to train by power in endurance zones. For a given power output, your HR will simply be lower.

Then you do an endurance ride in 90f and you miss your targets completely because you’re sweating.

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Not necessarily…

  • it depends on the individual. I can do endurance rides in the heat and it doesn’t negatively impact my HR in the slightest. I thrive in the heat.

  • it depends on what your “target” is…if your targets are based on power, you haven’t missed anything. You have just completed the ride at a higher HR

  • I am not advocating only using power. In your example above, I would argue that an athlete should be watching their HR and adjusting their efforts accordingly (which will still have them within their endurance power zone). I have also agreed that HR can be a useful metric for endurance training

I have been looking for an answer to a the question of VO2Max intervals. When training VO2 Max in running the intervals are designed with a duration and speed to elicit a specific HR. That HR would be the minimum HR defined for VO2Max. The goal is exert only the required energy to stimulate an adaptation. VO2Max (HR) as been measured on treadmill with appropriate equipment. Defining a power zone called VO2Max based upon FTP may not be sufficient to elicit an adaptation. Similarly, the power may be in excess of what is required to elicit a response (for the duration) not allowing rider spend as much time as possible at VO2Max. TrainerRoad in my humble opinion is good but should have HR incorporated into its VO2max intervals by design. Max HR should be acquired from the FTP testing and the ability to enter required VO2Max HR zones to ensure riders get the most benefit from VO2Max Intervals and Training sessions in TR. Any thoughts on this limitation to TR Training plans? Reference Jack Daniels book pon training and VO2Max.

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  1. welcome to TR!

  2. the problem is that HR lags behind effort, so you aren’t seeing how long you are truly at a VO2max effort.

I don’t know honestly know how comparable things like JD and TR are, in terms of training. There is no objective metric for running like power. So HR (or pace) become the best metrics available. But both are subjective metrics.

At the end of the day, we train to get faster, not spend a certain amount of time in a given zone (whether HR or power). IMO, focusing on how much time you spend on any given zone starts to miss the bigger picture.

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