Cardio load is nonsense in my opinion

[Dom123456]

I believe this has replaced the daily readiness, i'm not finding this new feature very intuitive, the goal keeps changing I have no idea how to gauge how much or little exercise is needed, weather a rest day or not basically, the only gist I get is that I need to do some sort of cardio exercise everyday, well I know that, it's good that it can be removed from the home screen.

Moderator edit: updated subject for clarity

[kayakmac08]

Curious to hear. My bet is that it'll say you're under-training.

[hovdeo]

😫😲😢

[RiekoC]

Hello @hovdeo 

What was your Daily Readiness score when you got the lower Cardio Target Load & where was your dot on the Past 7 days training line graph?

I've noticed that when my Daily Readiness score is on the lower side (under 40), my Cardio Target Load range will be on the lower side.

[hovdeo]

@RiekoC -new day, new opportunities!

i can see why a low readiness score would trigger a low target cardio load - that does make sense - you need a bit of recovery.

in the past two days, my readiness was 53 and 48 ("moderate") respectively, which could explain a small drop in the target cardio load from wednesday to thursday but (as i see it) not from 110 - 150 to 33 - 78, but perhaps 2 moderate days in row along with a hard vo2 session could trigger such. and, is such a drop a lot or not a lot?

yesterday, i ended up with a cardio load of 157 vs target of 33 - 78 - a smidgen above target one could say. this morning, with normal sleep, a very hard cycling session yesterday, and a high cardio load - my readiness is 90. target cardio load for today (friday) is now 16 - 40 and "you've been improving fitness lately and your readiness is high. aiming for 16 - 40 cardio load today will keep you on track to improve our cardio fitness".

a bit surprised to see a readiness of 90 - after 2 days with hard vo2 workouts - i feel a bit beaten up to be frank. Today's session is weights which together with a 30 min brisk walk during the day should get my cardio load above 40.

time to hit the gym!!

[RiekoC]

Hello @hovdeo 

Well at least you didn't get the message that you're at risk of under training.

It makes sense to me that your target range would drop some after 2 days of moderate workouts. However, it is surprising to see a readiness score of 90 after those 2 days. You must have had a good sleep score & Health Metrics to get a high readiness score.

It's always best to listen to your body. If you feel that you need to ease up on your workouts despite the high readiness score, then that's the best plan.

From what you've shared, it looks to me that you're doing what's best for you, which is the right move.

[hovdeo]

sleep was below average, below target. RHR was down 2 bpm. HRV was a up a wee bit. a readiness score of 90 would still be "too high". but, as you say - never let the numbers decide how you are supposed to feel. do not live by Fitbit scores, Garmin scores etc. As someone said somehwere here - you may have a super stressful day at the office but your HR is never above 70 - 75bpm - this is not captured by any "smart" watch.

readiness dropped to 70. cardio load target 16 - 40 "you've been improving......", slept like dog cr@p as i always do after a day at the gym. easy 1h45m 1000kj on the bike today. season opener in Omloop, Belgian spring classics, today. iykyk as they say.

[Shufflincrew]

3 days ago it told me that I'm at risk of overtraining so I stayed within the recommended load. Today I'm at risk of under training and it is recommended that I get in the 195 to 220 range. Yesterday my graph was right in the middle. Today it is way over to the left. I don't get it. This feature needs to go back to the drawing board.

[hovdeo]

@Shufflincrew- do not try to make sense out of this algorithm. it is all over the place. one day easy recovery training, as it suggested due to over training, and you are under training, as if an easy day or 2 would make much difference to your progress. stay in the range 2-3 days and you are under training.

but, you wake up in the morning and it says 96 - 144 as your cardio load - how on earth can one prepare a session to meet that target when you have no idea how the algorithm is working? i could potentially plan against zone minutes but converting zone minutes to cardio load is like PhD in black box, voodoo, oujia board etc.

[kayakmac08]

Yeah, it's not just you. The feature is whack for what seems to be at least a few reasons. I only reference it very cautiously. Definitely listen to your body and don't let it try to fool you with its toddler algebra.

[hovdeo]

more like an entertainment gadget, kind of like a tamagochi but it is fitbit that are feeding and nurturing.

[Shufflincrew]

Fitbit help does not help either. We keep getting the same canned algorithm responses. I feel like I'm spinning my wheels. Fitbit help also keeps referring back to Fitbit Community, but the community is just a place to complain or vent with no help.

[NameDuJour]

You're absolutely right! It's incredibly inaccurate and even downright dangerous. My favorite part is how the Fitbit app constantly contradicts itself when relating this metric to others.

[YachatsMike]

The difference as I understand it:

Readiness - a measure of your condition today.  Are you physically ready to do a vigorously intense exercise if you wanted to?

Cardio Load -- The amount of vigorously intense activity you've actually done today.  It's a measure of time and intensity.

Cardio Load Target --  a suggestion on how much cardio load you should rack up today to meet your weekly goal (maintain or gain) for cardio minutes without overtraining or undertraining.  If you have a rest day it will boost your target the next day to catch you up, if you have a hard day it will recommend you slow down.

[YachatsMike]

It is based on training impulse (TRIMP).  In it's simplest form, TRIMP is time x intensity.  The voodoo is in the intensity factor.  There are many methods used to come up with that and great academic papers to support why theirs is best.  It sounds like Fitbit rolled their own.  I sure would like to see it so I could evaluate it for myself.

[Chudders]

Plus, whenever I have tried to use my Charge 5 to record a swim, it kills it!  Yes, I do set 'Waterlock', it's happened on all the FitBits I have had that say they can monitor a swim.

[hovdeo]

ok, another week has gone and cardio load is just as confusing as ever.

other musings........... this morning, 90 mins with 5x5' vo2 max, one all out 5' followed by 4x5' 3x(40"/60") cardio load 37, 109 zone mins. fitbit avg HR 121, garmin avg HR 128 for the 90 mins - not crazy different. peak HR 172bpm. 

yesterday, i did 1 hr yard work (spring is nigh) - cardio load 29 , 24 zone mins, 100bpm avg HR.

same readiness score 68 and 69 respectively. same sleep score. how is it that the algorithm somehow converts 109 zone mins, intense cardio, to 37 CL and 24 zone mins, easy breezy, to 29 CL??? i don't know TRIMP but something seems to be way off, i would have expected a significantly higher CL today given the level of effort. 

it would be nice to get some understanding ref. the "logic" going into the Cardio load targets and cardio load calculation.

[PamJK]

I have been curling and as lead I sweep up to 6 rocks. I am 69 and supposedly above the fitness level for my age with a cardio fitness score of 32 to 36. I get about 40% or higher of peak heart rate and another 50% vigorous in a 2 hour game. Done that twice this week. Cardio load of 256 and 236 those days. Today I am told I have been undertraining!! I have read several posts where the response is that the target load will adjust over time. Would two months be long enough?? As well spinning for 20 minutes using a HIIT scenario only gets me a 30 cardio load. Seriously what a load of garbage. Now that the curling season is over I can see that my Fitbit app will forever be telling me I am undertraining as I won’t be spinning for 2 hours for sure. 
How is it possible that my fitness level is high for my age but I am undertrained. Sounds like this program needs to go back to the development stage! 

[kayakmac08]

Oh it's mostly trash. If I took it with more than a grain of salt I would have died from a heart attack months ago. Based on my experience, it seems that tiny variations in your sleeping HRV and average resting heart rate (aRHR) will move the needle on your Cardio Load far more than what your heart rate did during exercise sessions throughout the preceding week. And the problem with that, besides being a an idiotic weighting of variables to begin with, is that the HRV and aRHR measurements aren't especially precise anyway AND are easily influenced by variables entirely unrelated to cardio fitness/VO2 max (e.g., alcohol consumption, stress CPAP usage). So your Cardio Load score is moving based on crappy data, resulting in a butterfly effect of nonsense. This seems to be at least part of why it often tells you to go hard in the paint for days on end, regardless of whether your heart is spending a concerning amount of time in the Peak training zone and regardless of how much faster you're getting (which last I checked were rather important variables to consider in training LOL). It's not uncommon for me to have racked up 400 zone minutes, including 2 VO2 max workouts (utterly taxing), and Cardio Load is still telling me I'm at risk of undertraining and recommending to go get 150 more Zone minutes. No thanks, CardioLoad. Something's broken and I'm not adding my body to the list.

[callcat]

I’m turning 72 in a couple of months. Besides walking an average of five miles a day, I also recently started working out with the VR Supernatural app. This morning, my Fitbit app told me that, in order to “help me get back on track to improve my cardio fitness”, I should aim for “266 - 411” cardio load! Sorry - but I have other stuff to do besides working out. What is going on?

[RiekoC]

Hello @callcat 

What do you have as your Cardio Load fitness goal? If you have it set to Improve, consider setting your goal to Maintain.

I've read posts from users who have Improve as their fitness goal and get unrealistic Cardio Load Target ranges, like the one you reported. After they switch to Maintain, the range became more reasonable & attainable. Several users reported that their dot on the Cardio Load graph eventually moved from Maintain to Improve, where they wanted to be in the first place.