SethAZ 

That's very interesting. I have no idea how I'll end up using it over the long haul, since I've only just gotten it. My prediction is that heart rate will remain my primary planning tool, at least in the short term. It's entirely possible that as I gain experience with both, if the power output compared to heart rate ends up being consistent and predictable, the two figures may become practically interchangeable.

If that occurs, it's more likely I think to be after I've plateaued in terms of my cycling fitness. Since I'm still at the building stages of regaining cycling fitness after nearly two years off the bike, my hope is that the power output isn't consistent with heart rate; I'd like to see the average power per heart rate zone improve over a time scale of weeks or months. Seeing that will be direct evidence of the effectiveness of my plan.

Carbonfiberboy 

I use them both for all the reasons given above. Plus, I go much more by HR on competitive group rides because any current power reading really doesn't determine when I'm about to blow up, it's kj within some time period, which is pretty much the same thing as HR. I know my blow-up HR within a beat or two, no matter what my power is doing. Power is nice to have to limit damage and to set effort on long steady climbs, but when stuff is happening in the group, I watch HR. HR is also how you can tell if you're underfed or dehydrated, Power will eventually tell you about underfed, but by then it's too late. Power says nothing about hydration, again until it's way too late. On group rides FTP comes in real handy after an attack when I'm trying to stay out there.

I do all my indoor training with power, though for short hard intervals, HR is how I figured what my limit for X minutes was, by experimentation, but after that, I did them with power, increasing power when HR at the end of the last interval said it would be OK..Power is wonderful for being consistent and for limiting that stupid surge at the start of an interval, totally a feature of HR based training.

Which is all in the category of "what Psimet said," but longer-winded.

RChung

The best direct evidence of effectiveness is whether you're faster for longer durations, or more comfortable at the same speed for the same durations.

Carbonfiberboy 

As an example of the use of both, I just did a 30' sweet spot interval on my resistance rollers. I rode it at what is supposed to be 97% of my FTP (functional threshold power), the level set by a good guess, but kept it steady the whole way. It took 25' for my HR to get close to my LTHR (lactate threshold heart rate) and at the end it was 94% of what I think my LTHR is. I'm in pretty good condition but have a long way yet to go. It's the week for my FTP test and it'll probably be up a bit, at least we all hope that's what happens. In any case, my PM and HRM are in good agreement as to where one of my limits is, and obviously HR is much slower to respond than a PM set for a 3 second average.

If one is using a dumb trainer or resistance rollers, one can simply hold the speed steady to imitate a constant power output and see what HR does over time, rather than attempting to use HR to set the pace. One can record the speed(s) to be able to duplicate the workout.

guadzilla

^^^ I was gonna type this but Rob beat me to it.

I use power for training, and HR to gauge how my body is handling that training. Most of the time, i dont care about the HR figures but there are times when my HR is too high or too low for what I am doing and what the RPE *should* be, and at those times, i know that i need to make a change.

canklecat

Even if I had a power meter I'd still defer to my heart rate as the more important indicator.

But my heart rate and blood pressure are wacky due to various health issues and vary from day to day, even throughout the day. Between an auto-immune disorder, asthma, ridiculously bad allergies to everything airborne in Texas, etc., my resting pulse may be 58 one day and 98 another. My resting BP may be 90/48 one day and 160/100 another. It's just nuts. Depends on whether I need pseudo-ephedrine for sinus congestion, ephedrine for bronchial congestion, etc. Sudafed will elevate my HR and BP about 10 points. Primatene tablets with ephedrine can increase it 20-30 ticks. Hate to take 'em but sometimes albuterol, Flonase, etc., just don't work.

I had a couple of good moderate effort rides Monday and Tuesday this week and intended to go for some PRs on Wednesday with full effort. The main reason I got a proper bike computer was to monitor my heart rate. I noticed my HR hit 140 bpm just coasting down the 1/4 mile slope from my place. At first I figured it was just stress -- the most dangerous place I ride is my own neighborhood street, so I'm always tense until I get a mile from home.

But my HR didn't settle at all during the 2 mile warmup route to my usual 5 mile workout loop. And it hit 160+ as soon as I started the first climb at an easy pace, then pegged and stayed there for several minutes. My max HR, checked several times last summer under various conditions, was around 173. It's probably lower now. I set my bike computer alarm to beep at 161 to remind me to ease back, or as a gauge to whether I'm working hard enough on hill repeat intervals. But hitting 164 on an effort that's usually around 140 bpm? Not good.

So I changed my plans and just did an easy 20 mile cruise through the routes with fewest hills and least traffic. Usually my HR would be around 110-120 on that terrain at that effort, but Wednesday it was 140-160.

My legs felt strong enough to generate some power, but my chest was tight from allergies (pollen count is red-zone all this week) and my heart rate was warning me to ease up.

There will be other days.

RChung

I've been using a power meter for a reasonably long time, and I used a HRM for several years before that. Maybe 15 years ago my HR belt broke but by then I was so used to using power and RPE that I didn't bother replacing it. About 5 years ago I got a deal on another power meter "package" that included both a head unit and HR belt, so I bought it but left the belt in the box. Then last year I had to go on a 3 month trip to Europe and couldn't take my power meter so, after some reflection, I took the HR belt. If I don't have power then I guess it was kind of okay, but only kind of. When I got back I was happy to put it back in the box and resume riding just with RPE and power.

Robius

I use hrm to see how well I'm recovering between efforts. It's an important indicator about my form.

sirjag

Hello Mr. Isotope! Perhaps you can help me out here....I'm new to cycling...on my third year in actually....
Anyways I noticed that during the winter..on day it was around 61F and windy so felt like low 50s....I couldn't keep my heart rate up at all! It felt like i was broken and kinda ruined my ride....

Now that I'm back in spring riding my HR data is pretty consistent 155 beats or higher the whole ride....so what is goin on here?> Why is my HR so difficult to maintain in colder weather?

here are some of my typical rides:
https://www.strava.com/activities/3211333737/analysis
https://www.strava.com/activities/3217207058/analysis



JAG

colnago62

This is similar to my revelation on the subject. First thing I noticed after riding with power was heart rate during my rides had less peaks and valleys. It became more stable. For ride intensities from sweet spot and lower I don’t care about heart rate because it not really what is important to the workout. Now things like AC and VO2 work, like heart so I can look later and see how hard I actually was working. If I am really where I need to be intensity wise. I use morning pulse and fatigue score plus the form numbers from TrainingPeaks to determine my fatigue. It is pretty spot on for me.

Carbonfiberboy 

I ride in the PNW where your 61 is a nice warm day. Try 36° and raining hard for 75 miles. In any case, I've been riding with HR since uh, '96. I don't notice any change at all with lower temperatures. I do notice large changes with recent training quantity and intensity, especially in the first hour of a ride. Not knowing anything about in what condition and training state you were in this winter, no way to know much about your HR. But if you notice this all the time, I'd say you might have a mild case of asthma which is causing bronchial restriction in cooler weather. That could cause you to not get enough oxygen to work hard enough to raise your HR. You could see a pulmonologist uh . .. maybe in July. So when that happens again, if it ever happens again, take a deep breath and exhale as hard as you can. If you hear a wheeze, that's asthma all right. There are well known medications which you could use during a ride. Your PCP could fix you up right now. Rescue inhaler, albuterol. Small, goes in the bottom of a jersey pocket. Opens the lungs right up.

sirjag

thank you Sir.

tomato coupe

Heart rate monitors can be finicky in cool, dry conditions.

sirjag

now that is something i have noticed as well...i use a fit bit on wrist and when real cold i get poor readings...could be a contributing factor...good call sir.

RChung

I think the comparison isn't PM alone vs. PM + HRM. I think the comparison is RPE + PM vs RPE + PM + HRM since you always have RPE. I'm sorta surprised that many riders seem to think they no longer have to think about RPE.

It's as if they asked themselves the question, "Now that you have HR, are you still checking RPE?" and they answered "No."

Bah Humbug

I wouldn’t give up my HRM data due to having a PM any more than I would give up cadence or speed data due to having a PM.

Carbonfiberboy 

Good point. Having a PM for the last 9 months has really helped me to develop a finer sense of RPE. Our tandem doesn't have power, just HR, but now I can do a decent job of estimating my power output from pedal feel. That enables me to do a better job of guessing at time to exhaustion than just watching HR, which is sometimes depressed if I've been training hard on my single. More data is better.

RChung

Good point. I don't follow cadence, either. Cadence is a red herring.

colnago62

I will focus on cadence when doing drills designed to improve cadence, other than that, I ignore my cadence numbers. If my legs feel good, cadence is good. If my legs feel booged down or sun out, I shift till they do

Bah Humbug

I do better at some than others, and keeping tabs on it also helps track freshness. Maybe you have less value in it.

MoAlpha

Ha! I'd love to stop "thinking about" RPE, especially at the top end.

Seattle Forrest

RPE makes itself known, no checking necessary. At the high end, it's impossible to ignore.

HR data isn't something I look at while I'm riding, but it can be useful after the fact in several ways. It's cheap and easy to collect, I don't see any reason not to as a matter of course. Since I've been using a PM, I don't think twice about riding without an HRM if I forget it, power is clearly more useful, but it's better to have both.

RChung

Does "several" mean "3 or more"?

If I did a sport where there is no PM (like swimming or XC-skiing) maybe, but I don't do those.

Seattle Forrest

I find PWR:HR to be a useful gauge of my fitness, which tends to go down a little during the shoulder season. And I think HR is (probably) better for planning workouts and keeping track of cumulative fatigue because TSS doesn't distinguish aerobic vs anaerobic.

Bah Humbug

https://www.triathlete.com/gear/swim...ext-big-thing/
https://the5krunner.com/2017/12/11/s...r-trainesense/

I mean in general you're right.