Heart rate zones higher than power zones?

Hi everyone,

I got an issue that my heart rate zones from my Polar device do not match my Zwift power zones at all. Usually, my heart rate is pretty much one zone above what my power would suggest. E.g. if I am riding in Power Zone 2, my Heart rate is in Zone 3. Riding on Zwift was so much fun that I bought and “inhaled” the books “Training with a power meter” and “The cyclist’s training bible” already.

Regarding the heart rate: Maximum heart rate is set up correctly and realistic for my age. (192 bpm)
Zones are default as well.

I’m riding on an Elite Diretto XR-T, which can be mechanically calibrated via adjustment screws (the calibration was perfect straight from scratch) and I’m doing a spindown in Zwift once a week just to be sure the wattage does not drift.

Am I missing something here? Is it my lack of fitness? (New to cycling, just started 3 months ago and the ramp test suggests my FTP is 202)
Or is the test inaccurate and I should do the 20-minute test? If so, I’d be sad, because an FTP of 200 was my first goal. :slight_smile: But it doesn’t make sense if I keep spinning in the wrong zones all the time.

I also noticed that sweet spot training on the upper end of zone 3 makes my legs burn and I feel really sore after just 5 minutes at this wattage, with my heart rate being almost in Zone 5. So I guess something is wrong here…

Thanks for any advice!

Tobi

HI try the short ramp test and spend longer warming up. I personally never use a HRM as there is always so many variables that cause it to be inaccurate compared to power where either you produce it or you do not. with Heart rate you can be tired or stressed that can affect it greatly. Also when doing the ramp test ensure ERG mode is enabled. it will ensure a smooth ramp up to each level. hope that helps

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I think people generally suggest calibration from MyETraining over Zwift’s inbuilt calibration - might be worth comparing the values out the other end to see if they resemble. But defer to Elite’s over Zwift’s.

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Your issue is likely from using max heart rate to set your zones. Using the maximum heart rate model, you are relying on statistical averages as to where heart rates will distribute themselves by zone. Given that you are new to training, your fitness level is unlikely to fall within those statistical means. The best practice for setting your heart rate zones is by using Lactate Threshold Heart Rate (LTHR). Pretty much every fitness software is capable of giving you zones around that zone. The premise is that it is personalized to you. It is using your heart rate at your current fitness to establish zones that will more accurately approximate the strain you will incur during different power outputs.
The gold standard method of testing your LTHR is to do a warmup then ride as hard as you are able to pace yourself for 30 minutes (treat it like a race but don’t start too hard and completely fall apart). You then take the average heart rate over the last 20 minutes of that test - using the last 20 minutes helps to evaluate your true steady-state plus cardiac drift/aerobic decoupling which should not be averaged with your first few minutes of fresher legs and settling in. If you are struggling to pace that type of effort and do workouts with steady efforts at your FTP (at least 5 minutes) you might be able to get a rough estimate from those as well by looking at where your heart rate peaks and plateaus in those efforts, but testing is definitely preferred.
As you would expect, when your fitness improves, not only will your FTP increase, but you will find that the heart rate you can tolerate will increase as well. Your LTHR will go up and your heart rate at different zones will come down at the same time which will keep your heart rate zones more closely paired with your power zones. There may still be some decoupling, especially later in the workouts as you continue to build your fatigue resistance, but you won’t see immediate mismatches as your zones will be more appropriately set.
Much like a ramp test, your LTHR should be reevaluated every 4-6 weeks in your first year to 18 months of cycling. Eventually, you will hit something close to your genetic potential and that number will remain pretty stable for a long time with slight attrition for age and may drop with protracted periods away from training.

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Hi everyone and thanks for the tipps!

I was checking the calibration on the Elite app and it gives me a number that should fit to what’s written on a label on the bottom of the trainer. As far as I understood these trainers are factory calibrated and the calibration result is placed on this label. There is an adjustment screw you should turn in case of the number from the app does not match the factory calibration numbers, but mine are perfectly on par.

Regarding FTHR: Silly me was writing the test procedure down after reading it in the book, but I didn’t bother. I’ll rest today and try my best on a 20 minute FTP test tomorrow, so I can see possible differences in FTP and get an idea of what my FTHR actually is. I’ll adjust the heart rate zones on my Polar device accordingly and let you know what happened.

Thanks for the help so far!

well, it’s same for me, and I’ve never really considered it a problem other than showing how unfit I am XD

#fasttwitchproblems

Nice to hear I’m not the only one. :stuck_out_tongue:

Well, gained almost 25 kilos during the past two years of lockdowns and stuff. Far away from being fit…

So I just did the 20 minute FTP test as good as I possibly can. Messed up the pacing because I was holding up to my ramp test FTP value of 200 watts. I fatigued halfway and ended up getting an FTP of 172! That is 15% lower…

Summary:
Ramp test: 202 watts
20 minute test: 172 watts
FTHR based on 20 min test: roughly 168 BPM

This feels a lot more realistic. With an FTP of 202, sweet spot intervalls have killed me. There is no way I could have completed the SST with 2x20 mins of sweet spot intervals.

Now the big question: Why is my ramp overestimating by 15%? And can I keep doing ramp tests but correct the FTP value down by additional 15% to be more accurate?

ramp test also comes up slightly higher than 20min FTP test for me.
better to ride FTP test based on heart rate in my exp.
go slightly under threshold for first half then above threshold for 2nd half.

ramp test will overestimate if a) you are getting out of the saddle or b) you are naturally strong at anaerobic efforts.

anyway it’s not ideal to compare FTP from different test methods - pick one and stick with it and try and ride it the exact same way each time (apart from going that bit harder each time, hopefully :D)

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There’s also the issue of the number of zones… HR zones tend to go pretty universally from 1 to 5, whereas probably the most popular power zone model (Coggan etc) has 7 zones, meaning e.g. that HR zone 4 and power zone 4 aren’t the same thing.

Zwift only shows 6 power zones, but I think that amounts to the same thing minus a specific boundary point between zones 6 and 7.

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This might make sense in my case. I did the cycling phenotype test mentioned in one of the books and ended up leaning towards the power profile of a sprinter. I have never seriously cycled before and I haven’t touched a bike in the past four years, yet I was able to produce 970 watts peak power as a bloody beginner with only 4 weeks into Zwift and zone 2 riding at an initial FTP of 140. Also, my body type is definitely endomorph, so I gain muscle and fat very easily, which made me have strength advantages back in the days where I was lifting weights. I’m certainly not strong, but might there be an imbalance in between my muscle strength and aerobic engine causing overshooting the short ramp test intervals?

The funny bit is that the short FTP ramp tests I did in the past seemed very accurate. Initial test: 140 watts, 6 weeks later 167 watts. Only when I started to use the regular ramp test I have this issue.
The only difference is the short test increases 10 watts per minute, while the regular one does increase by 20 watts per minute. I guess this faster watt incline makes it inaccurate.
I’ll program myself a workout that does increase in 10-watt steps per minute and then look at the average watts in the best 1 minute myself. I think this steep incline in power per minute might be the issue for the ramp test’s inaccuracy…

@Anna_Ronkainen

I noticed this as well reading the books from Coggan and Allen. As far as I remember, Zone 7 is an all-out effort/sprint to complete depletion, so I guess we don’t necessarily need a zone for this since all you need to reach that zone is to go as hard as you can. At least that was the way I understood this.

Edit: I also noticed that the FTHR based heart rate zones differ a lot in between Coggan and Allen, so I am also not sure which of those two to rely on. :stuck_out_tongue:

Hi Tobias,
maybe another perspective might help.
I started zwifting in February 2021.

As long as you still get DOMS (delayed onset muscle soreness) and FTP gains after endurance rides you can safely ignore any statistics and just ride away (the more time you can put in the better).

This took me from 230W FTP up to 270W FTP in 6 months while giving me enough time to fix my bad indoor setup.

Training sessions i use:
ENDURANCE: 2.5 hours @ 200W-220W
VO2-MAX: 5x(4 mins on, 4 mins off) @ 110% FTP
SWEETSPOT: 3-6x(10 mins on, 5 mins off) @88% FTP - depending on preexisting exhaustion
Zwift races

Each session has a different long-term goal:
Endurance sessions will slowly build you up without burning you out. Do not sprint.
VO2 Max sessions are used to pull up my FTP.
Sweetspot sessions are used to push up my FTP.
Zwift races are there to have some fun and socialize - without them i don’t have the spirit to push through the long training hours :slight_smile:

I focus on VO2Max sessions and sweetspot sessions every other month in order to pull and push my FTP.

I am currently at 293 W FTP.

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Hi Tim,

thanks! Gonna give it a try since I’m just reeeeally new to cycling. I did some mountain biking for two years but I wasn’t following a specific plan and this was 4 years ago so I guess you can call me a bloody beginner. I’ll try to focus on some gentle Z2 stuff. BTW, I just did ride in Zone 2 today with my lower FTW of 171 watts and it felt much better. Like I could go on for hours, but feeling the work done by the legs.

Hard to judge all the training and sensations because as a bloody beginner it’s almost impossible for me to guess the fatigue as of whether it’s not enough to improve, spot-on, or whether I’m asking too much of my untrained body.

Cheers!

Tobi

Remember, fitness improvement takes place during rest, not exercise. Obviously you need to exercise and that starts the process but if you don’t get appropriate rest, you won’t get as much fitness improvement as possible. And the potential for injury increases exponentially during overtraining.

Absolutely, though I am not sure whether I do it right. I was ramping up my volume the past months and at the moment I average at about 50 tss for endurance rides and sometimes 70 tss for some interval training.

The day before an interval session I take a rest day or spin in Zone 1 for ~45 minutes to be recovered for the particular session and when I feel OK after the intervals, I do some Z2 work the day after, followed by a rest day or again Z1 spinning. I like doing these active recovery sessions because I’m still motivated to jump on my bike and to prevent me picking up pace again, I use ERG mode in Z1 to make sure I stay at the low power levels.

I thought I can use Training Peaks recommended recovery periods for given TSS values, which they say are:

TSS less than 150 – low (recovery generally complete by following day)
150-300 – medium (some residual fatigue may be present the next day, but gone by 2nd day)
300-450 – high (some residual fatigue may be present even after 2 days)
Greater than 450 – very high (residual fatigue lasting several days likely)

Based on this information I “should” theretically be able to work out daily given my TSS has never been past 100 in any workout since I started zwifting. But I guess these figures do not apply to beginners at all?

Then again there is the CTL, ATL and TSB values, where Training Peaks recommends the TSB (Training Stress Balance) is between -10 and -30 for optimal gains without high risk of overtraining. Based on this I’m in the optimal range even though my TSS are kind of low.

And then there is my body feeling and heart rate I try to monitor each morning, as well as my sports watch giving me my heart rate variability during the night I use to determine how much stress I have overall. Generally the past week I felt very fatigues whereas I lowered my training volume and intensity.

So what can I rely on? :stuck_out_tongue: Is my sense of fatigue on a normal level, or are the metrics off since I’m a beginner? I’m definitely lacking the experience you guys have.

As for recovery: I’m trying to get 8 hours of sleep, going to bed at roughly the same time even on weekends so I don’t mess up my sleeping habit. I also got an old massage gun I use every now and then on my legs and after a ride, based on the calories needed, I mix myself some kind of a recovery drink with some carbs and proteine, then get on the sofa. Is there anything wrong with it? I feel like I don’t necessarily need this at my current beginner levels, but I thought it won’t harm.

So if you spot anything suspicious or got any tips: shoot! Happy about every advice I can get.

Cheers

Tobi