Improve Cardio load (TRIMP) accuracy

[maxperron]

I train consistently and understand load metrics like TSS, TRIMP, etc. Tried Fitbit's new cardio load feature but it’s off. Example: I tracked a TrainerRoad session with HR only (spinning activity). Fitbit gave a cardio load of 19, while intervals.icu showed a TRIMP of 136. This feature feels unreliable in its current state.

[maxperron]

The issue seems to be with the spinning activity, it looks like the calculation is off for this activity. It should not since cardio load is based on HR.  Runs give me the cardio load and TRIMP score. 

[maxperron]

Another day, same bug. Today’s training should have a TRIMP load of 134, but Fitbit gave it a cardio load of 79—hilariously off. Pretty sure the PO should make this a priority for the next sprint, or maybe they're secretly on a rest month themselves! 😉

[punkabilly]

I thought I was the only one.. 

I can do an hour high intensity race simulation with plenty of zone 4,5,6 and get a load of 8 while I'm laying on the floor in a puddle at the end.

I do an easy 5k run with low HR for 30m and it gives me 80. 

Now it tells me I'm over training, recommending load 1-30, and the coaching tab is suggesting running intervals.

[LizzyFitbit]

Hi @maxperron, and thanks for taking the time to share this product feedback about improving the Cardio load (TRIMP) accuracy with us. We rely on feedback like yours to help us develop products and features that we know our community wants to see. If this product feedback receives votes from other customers and gains popularity, it will be shared internally with various teams at Fitbit. To learn more about how Fitbit decides what product feedback is developed, visit our FAQs.

Watch this space for status updates. In the meantime, try visiting Health & Wellness to talk with other members about all things health and fitness.

[ThoFi]

Same here. Strangely, Spinning is called Indoorcycling in the German translation. The term Spinning is well known in German. No need to replace it with another English term. Anyway, manually starting and stopping a session Spinning / Indoorcycling on Pixel Watch 3 of 45 min, 133 bpm mean HR, 140 watts (ergometer), 80%+ in Vigorous gives me a Cardio Load of approx 5-7! Have seen this behaviour many times. There are also many people reporting the same behavior on Reddit. So yes, there is something seriously of with Cardio Load while spinning. Zone Minutes are fine.

[phatbitzr]

I use fitbit, along with myWorkouts app with a separate dedicated HRM.  The TRIMP/Cardio load numbers correlated pretty closely.

Activity / Fitbit / myWorkouts
Spin / 104 / 117
Spin / 182 / 172
Ride / 76 / 71
Spin / 220 / 210
Spin / 261 / 229

[ThoFi]

@phatbitzr 

The spin session you did, was that a spinning workout with lots of arm and body movement or more sitting still on the bike an not moving your arms? There is a theory on Reddit that Fitbit needs to register movement (arm and/or GPS) to consider a workout is going on. According to this theory riding a bike is fine, since movement via GPS is recorded. Spinning with full body workout is fine, since a lot of arm movement is going on. Sitting on a stationary bike and just cycling is not fine Cardio Load wise, since no GPS and arm movement is recorded. Fitbit might interpret this just as a period of doing nothing with an elevated heartrate condition and therefore not counting it towards Cardio Load. @LizzyFitbit Please Fitbit team can a Dev comment on this. A manually on Pixel Watch 3 (or another Fitbit device) started and stopped Spinning / Indoor Cycling session (with no arm movement) should give a correct Cardio Load / TRIMP value, since a lot of people use this method for training in the cold winter weather, when riding a bike outdoors is just not feasible. Again many more people on Reddit have the same issue.

[phatbitzr]

@ThoFi 

I never do any of the arm movement stuff on stationary bikes, in fact, I have the app set to auto-stop and frequently, and annoyingly, it will ask me if I want to end the exercise.

For the spinning sessions, I do have the fitbit recording an exercise.
Looking into details for one spinning session, I did not start recording the activity, and it took the fitbit 8 minutes to recognize I was spinning for it to start recording.  But in that 8 minutes, my cardio load went up by 12.

For the bike ride sessions, I am not recording it, but the fitbit will recognize a bike ride starting and record it via its SmartTrack feature.

[ThoFi]

@phatbitzr 

Thanks for the quick reply. So, the problem is probably more complex. Unfortunately, Cardio Load is not recorded correctly for me while spinning.

@maxperron 

Thanks for pointing out that intervals.icu works for you and gives you correct TRIMP scores ( comparable to Cardio Load). Since for the time being I can not use Fitbit to measure fitness level and progression, I also looked into intervals and will sync and analyse my workouts there.

@LizzyFitbit 

Can you please consult with a dev on this, since there are more people (e. g. various posts on Reddit) having this issue.

[jtuchscherer]

I am running into the same issue. I did a 120 min Peloton ride yesterday and 80 minute ride today. Strava and Peloton both show the load of these workouts as very high (Strava: relative effort; Peloton: strive score), much higher than my recent outdoor rides. But Fitbit assigned a cardio load to the Spinning exercises that is about a quarter or a fifth of what I would see in a comparable (heart-rate wise) outdoor ride. Now, the watch tells me that I am under training, even though Strava tells me the exact opposite. 

[rgirling64]

Same issue for me. I sync workouts from a third party app and the Fitbit app shows stupidly low cardio low numbers, despite having my heart rate data. Would love to use this feature but it's pointless at the moment.

[Fastfred1959]

I would encourage all people on this subject to add your vote to remove this inappropriate, shaming Cardio Load  tile from Fitbit.  Do you actually need to be reminded to hit your Cardio load numerous times a day?? For people that have eating disorders this is beyond terrible and Fitbit/Google doesn't care.

[Moja95]

Agreed - cardioload is hilariously overestimated while running. Additionally it seems the target load is useless if it is only based on he last week as an indicator of one's fitness as one might be sick, not feeling well, on vacation etc. In my case I was getting over training warnings for a week because I did one single 5k run after Christmas holidays. 

[crobot]

I'm experiencing similar issues when logging Peloton rides, except for me the app is actually showing the cardio load associated with the exercise as "Cardio Load: 0".

The total daily cardio load goes up, but the app is considering them "general activity". The Peloton workout, which is added via Peloton's Fitbit integration includes duration, HR data, calories, miles, avg speed, etc but lists the load as 0. The total load chart for the day shoes the load increasing during the time of the workout. This results in the metrics displaying logged workouts vs general activity as being incorrect as the "load" from the workouts isn't actually tagged to the workouts themselves

I can't speak the the accuracy of the numbers, more generally, which seem to be some of the complaints in this thread.

I found a reddit thread reporting the same "zero load" issue for general "indoor cycling" activities, so this appears like it's not just Peloton workouts and associated with how Fitbit is treating spinning workouts - which tracks with what's being reported here as well.

https://www.reddit.com/r/fitbit/comments/1gebfz7/indoor_cycling_is_giving_me_zero_cardio_load_is/

[crobot]

Here are some additional Reddit threads detailing the same issues. Anecdotally it seems that several people are reporting that the zero-low cardio load readings may be due to wrist movements:

https://www.reddit.com/r/fitbit/comments/1huwviv/trying_to_understand_cardio_load_why_does_my/

https://www.reddit.com/r/fitbit/comments/1hz6xlu/cardio_load/

https://www.reddit.com/r/PixelWatch/comments/1fw7rt4/spinning_does_not_contribute_to_cardio_load/

[phatbitzr]

@crobotThe Cardio Load for the exercise showing zero might due to the exercise being imported instead of being recorded by fitbit.  When I manually add an exercise after I had already done the exercise, the Cardio Load for the exercise would show zero, but my total Cardio Load would go up.  Maybe it doesn't do cardio load calculations retroactively.

@Moja95Cardio Load is a relative number.  If you are sick last week, then it will see you are not exercising enough to maintain your fitness level, which if you keep up the lack of exercise, will certainly be true.

[Saigdee]

I have the same issue. Did a 40min spin class with 137 average bpm, a high of 171 bpm and 41 zone minutes. It’s showing a cardio load of only 5 even though the time series chart for the day went up by 50 during my workout. In comparison, my gentle walk there (30min, 109 avg bpm) was double at 10 cardio load, and my walk home (45min, 113 bpm avg) is showing 19 cardio load!!

[davidmcastro]

Cardio load is frustrating. 63 year old with an excellent overall cardio fitness score. Cardio load set to improve. If I hit the goals suggested, Fitbit tells me I'm maintaining. The goals sometimes are aggressive. Eg minimum today was 160, which requires close to 2 hours of moderate zone activity or less with quite a lot of high intensity training. It is hard to plan work outs as the load recommendations swing wildly day to day. Last week the goals were reasonable... Eg 80 to 100. I exceeded the goals only to be told I was at risk of undertraining this week. There has to be better way.

[Rathmir]

I spent 62 minutes spinning.  I use zwift and am able to track several metrics.  I import my zwift workouts into Strava. My cardio load for this workout was 23. My average heart rate was 167 which is in my "peak" zone according to Fitbit. My relative effort in Strava was 177.  There is definitely a discrepancy between Fitbit cardio load and other apps data points.

[Rathmir]

I got an update to the watch app today, so I just did a regular workout, with no changes from what I would normally do. 100 minutes, average heart rate 163, Strava training impulse of 275.  Fitbit? 15 cardio load. 

My next workout I will try moving my watch arm while I cycle. For science. 

Pixel watch 3, btw.

[Rathmir]

Today was a recovery ride day. 45 minutes, 144 average heart rate, only 45 relative effort in Strava. 

I moved my arm every few minutes doing "weightless curls" and the Fitbit app shows a cardio load of 85.

The "lack of device movement" theory seems to hold some weight in this sample size of 1.

Hope the devs can take a look at this bug so indoor cyclists can have more accurate data in the Fitbit app.

[Llitalien2]

Hahaha, this cardio load measurement is laughably in accurate when using stationary bicycle (Peloton). App now claims I’m under training when I’ve ridden five days straight days with sweat dripping/heart pumping 90 to 120 minute Peloton rides. Incredibly inaccurate…needs to be fixed.

[soeziesplace]

I also noticed that the cardio load seems off by a lot. It does not seem to be able to accurately register the impact of a training. Coupled with the fact that I now get daily reminders to hit targets of 40 to 80 cardio load because of  'undertraining' (haaaaahaaa, I have 4 intense trainings per week -heartrate 135 average- and then 3 days of active recovery and mobility), the feature is annoying. Please improve it or make sure that we can disable it.

Also: since the introduction of the cardio load, my condition score dropped by 11 points, just overnight. Nothing has changed. Training consistency and intensity is similar to before.

[LouisR]

I currently use a Charge 6. My Fitbit data goes back for 10 years. My data and physique have not changed much over the 10 years, I am a little lighter now. I am watching the new 'Cardio Load' function on my iPhone App. It seems to correctly register when I do more or less intense activity, that's my subjective opinion, but my first month of data is headed 'Overtraining' and almost every day I am getting a message to 'Take it easy'... 'slow down and recover...Target 13 to 40 (sometimes it makes other suggestions) cardio load today..'. I am 67, I walk my dog at a swift pace of 6KPH for an hour each day, I usually do daily jobs in the garden or on the house, every second day I also go to the gym for an hour of weights. Cardio Load is giving me scores of 75 to 180 most days, on rare occasions it'll be 50. I certainly do not feel that I am wearing myself out! What is Cardio Load function really telling me? How do I use this new function effectively?  The 'take it easy' messages are making me feel like I am hurting myself and should slow down but I have been doing the same amount of activity for years. 

[punkabilly]

60 minutes of peloton zone 2 and zone 3... Cardio load. 0.

ZERO.

55 Zone minutes. 30 in vigorous, 25 in moderate.