Crescendo - Heart Rate Zones

Hi, I did Crescendo for the first time this morning and for most of it my heart rate was well above the zone 2 expected according to the display, touching 1 beat below my LTHR at the end of the highest power step. I am typically finding the morning workouts harder than the same one in the afternoon, but hoping that passes.

In short I am wondering if I am getting the right training effect from the workout?

In long I have been reading about the importance of of the first lactic acid inflection point, where the base levels of lactate just start to build up, and wonder how best in increase it. Endurance workouts seem like a good place to start, but since I felt like I passed this first threshold before/around the 75% of FTP step would I be better off doing something different? I am currently following the MTB preseason plan, wk 1.

Those HR zones are wrong in the two hardest sections. It’s not you.

The hardest one is 90% of threshold power so you’d expect HR in Z4 as you progress through that.

It’s just an error in the HR tags.

If it’s not been bug reported already I’ll go do that.


For what it’s worth I did Crescendo a couple of days ago and my HR was well over the suggested zone, whereas in most workouts the zones are pretty spot-on - I think there’s an error in the suggested zone(s) in Crescendo.

I’ve reported this.

RPE numbers are wrong in the same way HR zones are

The main thing is the power is right as the workout is about going up to sub threshold but no higher. So if it’s plan, do it as prescribed and switch HR display off if you want in the settings as power is the main thing.

Hope that helps.



Thanks all, much appreciated.

1 Like

Was about to post about this and saw this thread first.

I can confirm it’s still incorrect (HR zones) and the description of the workout should really be altered.

My FTP is 304w and I was holding 275w (up from 260w the block before)… for me I call this comfortably hard, it’s no way easy, but I’m not holding on either.

1 Like

I know this is a lot later but it seems it is still incorrect. I was well into Zone 4 pretty much for the central 25 minutes or so. My HR was about 10-15 beats higher than the suggested max for those sections. I at first, thought it was me but couldn’t figure out what was wrong but apparently it isn’t me as this issue hasn’t been rectified yet. This is a hard workout in my opinion especially with the suggested cadences as well

@Cody.Moore @David.McQuillen.KoS any thoughts to the above?

1 Like

i noticed something similar,
but i never touches hr zone 3

is there a way for wahoo, that they can evaluate the cthr,
especially when doing 12 week plan, or is by purpose that u only doing a hm in the middle?
my zones are way of and way under

Huh. When I did Crescendo my HR peaked at mid-zone3, probably spent 5~6mins in that zone, the rest below that. It felt like I was working at that point, but there isn’t much chance for it to get too high and stay there before coming back down again. I’m surprised at the reports of people being well in to HR z4.

It probably just goes to show how variable this stuff is from one athlete to another, even on a relatively smooth profile (i.e. not HI intervals). the above experience was a while ago now, but on a fresh 4dp profile from a few days before.

Edit: I’m really curious now. I could do with an endurance ride - I might fire this up soon and look closely. Watch me blow through z4 and feel stupid!

it was a constant hr zone2 ride

1 Like

I have found something that may be relevant (or will be if this is the reason for the discrepancies) The zones in my athlete profile are calculated as a % of my cTHR and NOT a % of my FTP. These zones and target heart rates are the suggested ones we see in all of our workouts. cTHR is your expected heart rate when riding at FTP and is calculated @98% of your 20 minute 4DP FTP test. For me my CTHR is 136 bpm so my Zone 2 by this method is 70-87% of that which is 96-118 bpm and based on this my Zone 3 is 88-95% which = 119-129 bpm (I have a low max heart rate) Now, Crescendo states that the max is 90% of FTP and not 90% of cTHR! My Heart rate @90% of FTP would be 135bpm almost exactly what it was during the harder efforts on this workout whilst the suggested HR shown on the workout was a lot lower because it is calculated differently. This throws up other questions because how many other workouts are based on % of FTP when the athlete profile and the suggestion HR ranges on each workout are calculated as a %of our cTHR? hope this makes sense? Just another point as well I have been doing my Zone two workouts based on what I see on the workout page but in reality a zone two ride should be 60-70% of FTP (127-149 watts) which is higher than the 70-87% by the cTHR method (118-138 watts)??

Hi everyone – sorry it took me so long to get to this. Just went in and fixed it up - hopefully that sorts it. Let me know if you still think things are out of whack.


Hi can you clarify what you have done please? When I did this today the hardest part was 90% of my FTP which was 192 watts and that was spot on with what was showing on the workout which took me into top of Zone3/lower Zone4 around 135-138bpm. Has this been changed now to reflect 90% of CTHR which will drop me down to a HR of around 123bpm and about 160-165 watts which will keep me in the CTHR zone 3 space… A big difference. I am also getting a bit confused regarding this as when you go into the settings before doing a workout you can adjust everything as a % + or - of your FTP but none of the workout targets are using a % of FTP but a % of cTHR . If you want to do a workout at 90% of your FTP the workout will show you a HR of 90%of your cTHR which is lower or am I missing something here??

Power targets have not changed. Just adjusted a few RPE and HR zones to better line up with them.

Thanks, so a straight forward final question that has not yet been answered in my previous comments. I thought Zones were determined by a % of max HR but SYSTM calculates Zones by a % of cTHR which gives a lower value. Which of those two should we be using to ensure we are training with the correct intensity for each Zone? Thanks

Zones can be calculated by either method, in SYSTM they are calculated as a percentage of cTHR, I’ve found zones calculated this way more accurate in terms of RPE and talk test, because cTHR as % of max HR varies between individuals.

Everything You Should Know About Heart Rate Training | Wahoo Fitness

1 Like

when i am doin a plan, my cthr shifts as well, so
could there be a solution that systm evaluates these shifts and adjust the hr zones automatically ?

1 Like