Why does my zone 2 performance suck?

The power numbers I produce on the turbo and on the road are almost identical and my heart rate matches up with these power zones on the road for zones 3+. I currently have an FTP of ~295W (4.21w/kg) making my zone 2 power 162-220W and when I ride on the turbo these numbers correspond really well to my zone 2 heart rate of 115-141bpm. But when I ride on the road I have to keep my power way down at around 55-60% of FTP to maintain a zone 2 heart rate, otherwise it easily moves into zone 3. For example, if I ride at 175W on the turbo my heart rate is steady at 125bpm, but on the road I would struggle to keep it below 141bpm and it would drift up to 145bpm-ish, despite it feeling super easy.

I don’t really understand why this is and it means my zone 2 rides outside are about 50-60W down on my turbo rides and often means on long rides I average zone 1 power.

Anyone got any thoughts? or training tips? Should I just ride in zone 2 power and ignore HR and look for an improvement over time?

Watts should follow HR. Your FTP is not correct or was and has changed.

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Hard to say. Temperature and hydration are the first two culprits that could make heart rate creep higher.

Or if you’re mentally a little more stressed. :smiley: Are you riding in traffic? One time I hit a road crack in the dark and side swiped the passenger door of the car in the lane next to me. Even though I was riding at a Z2 power my HR went up to 90% max for the next 20 seconds or so.

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Same powermeters?

yeah i’d ignore the heart rate as an issue, but look into it for curiosities sake. Probably temperature if I had to guess right off the bat

Go by watts

same powermeter and heart rate monitor, calibrated before every ride

very little hot weather here in England, so most of my turbo rides done in warmer conditions. Hydration could play a part, but watts to heart rate ratio doesn’t really change over a long ride ride so i don’t think its a big affect.

Are you able to pedal continuously outdoors, or are your rides more start/stop and/or up and down hills?

Few reason i have had same situation:

  1. Long period only indoors (winter) = just pedaling/no need to focus on anything/steady power
  2. Hot weather (>25c and not adapted to it)
  3. intensive period without long easy rides
  4. not enough sleep/no deep sleep/bad recovery
  5. lack of base
  6. bonus) Because i love riding my bike so i get so excited :slight_smile:

I would try to keep avg power at least 60% (for easy rides) and see what happens in couple rides/week(s). Harder rides/intervals sessions don’t mind it.


Oh yeah! That’s perfect temp for riding, you lucky dude! If it’s not raining, anyhow.

But, look, I think I can prove beyond a shadow of a doubt that you can ride at >60% IF for hours outside and maintain a HR <140bpm. I’m quite confident it’s true. :smiley:

If temp & hydration are primary ‘potential issues’ then secondary issues might be stimulant use (I mean caffeine, of course) or maybe make sure you really do have an FTP number that’s determined by a valid test consistently applied. (eg was your last ramp test or whatever test you use a legit, solid test result?)

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Here is my theory. Riding outdoor makes you engage more muscles (e.g. core, glutei) which draw on oxygen pushing you out of zone 2. Another possibility is that you ride with a hunched back and have to harder engage breathing muscles which in turn again draws on oxygen.


pedalling continuously isnt a problem, recently did a 3.5 hour ride with only 3 mins of coasting and 2 stops, 1 for a traffic light the other for a nature break. but average power was only 0.56IF to maintain zone 2 heart rate

Just a curious idea about how to resolve this: if you have the ride in a file with GPS and elevation and power data etc. can you export it as a file and import it into a program that will interpret it as a course? The idea is that it would be a controlled trainer workout where you match your earlier effort exactly on the trainer, and then see if there are still differences in the heart rates. There are so mny reasons why this might not work, but it might maske an interesting experiment. Cheers


Average, or normalized? IF uses normalized, doesn’t it?

very interesting idea, i don’t have a smart trainer though

i look at average, but on these rides they are only 5 watts or so different over 3-5 hours

If you put it into BestBikeSplit you can import it into TR and ride on your normal trainer.

I get this too (though not to as large a degree) and I think pacing and the variable intensity of outdoor rides can often be the culprit. If I’m regularly hitting threshold or above on hills etc my average power ends up being lower than when I hold steady Z2 watts for the entire ride indoors. It might also pay to look at your indoor vs outdoor setup as a whole- nutrition, bike fit, gearing, warmup/cooldown etc.

This affects me a lot too. My town isn’t very bike-friendly and I’m a nervous rider at the best of times. I can see my HR level right off when I pass the intersection that heads out of town.

I definitely have times where my RPE feels much lower than what would be expected at a given HR, generally it’s when my HR is in Tempo zone (150-159 BPM) and my RPE feels like it’s in Endurance/Z2. I look at my BPM and think: “I should be closer to 140-145 given how this currently feels”. Is this what you’re experiencing?

In other-words, my heart rate is higher than it feels like it should be for the given “effort”. Usually it’s almost always when I’m trying to ride “endurance” outdoors. I think part of it can be due to the sensations of riding outdoors. Wind, micro changes in grade–things that you don’t have on a trainer. You might not realize it, but you’re putting out slightly more power many times to compensate for these little changes.


HR doesn’t matter for evaluating how hard an effort is.

Use HR to look for decoupling. That is ‘when maintaining a steady state effort does your HR trend up?’ If it does your HR is decoupled from your effort at that power meaning you’re riding at an effort level beyond equilibrium for that duration. That equilibrium could happen at 120, 130, or 160 depending on any number of factors.