Incorrect calories calculation tracking cycling with Surge

[Igorus]

I have tried to use the Surge to track my small daily rides. Unfortunately the Surge is really bad at making a decent calculation of the calories burned during the ride (I won't mention the poor heart rate measurement readings, as those don't apply to cycling alone).

Let me give an example. I just finished a 15 km ride on a normal tourist bike in 1 hour (not a road racer), going slow and enjoying the sun and nature. My average BPM was 86. Probably a bit higher, as the Surger usually gives me couple of POOR-measurements (POOR = Point of obligatory rest, as I call them) during the ride, where my BPM drops to slightly above the resting heart rate.

Here is an image of the ride

So during 1 hour, 15km, with 86 bpm, I burned 102 calories and got NO active minutes. I was in the fat burning zone for 10 minutes. 102 calories????? That's almost the same as sitting.

When I enter my data on http://www.bicycling.com/training/weight-loss/cycling-calories-burned-calculator

I get a calorie burn of 288 kcal.

Let's compare this to a slow walk:

So 28 minutes of slow walking, with an average pulse of 77bpm and I burn 156 calories.

Let's compare both, 1 hour cycling, a higher average bpm but a 3 times lower calorie burn? How the beep is this possible Fitbit?

One can easily see the cause of the miscalculation by comparing the graphs. Somehow Fitbit assumes that during my ride all activity below 95 bpm and/or 20km/h is the same as sitting, as it calculates a burning rate of 1,6 kcal per minute. Only for a moment the burn rate goes up to 4 kcal per minute, as my pulse gets to 98 bpm.

During the walk, the Surge uses a burning rate between 4 and 6 kcal per minute.

Who wrote that algorithm for calculating the calorie count during cycling? Does it assume I am being pushed by a moped or going downhill for 15 km? I bet the GPS and distance/speed data is not used to calculate the calorie burn, it's probably something simple like <95 bpm 1,6 kcal/min, >95 bpm <118 bpm 4 kcal/min, >118 bpm <130 bpm 6 kcal/min etc.

Instead of releasing minor updates to the sleeping schedule, Fitbit should address this issue or the horrible step count accurancy. It's a joke really.

Moderator Edit: Subject for Clarity

[justaguyoutside]

And when i swim a mile and a half in an hour and 5 five minutes when i log the exercise it lowers the calorie count. i use more calories according to fitbit sitting on the couch.

[RobertoME]

Hi there @Igorus and welcome aboard @justaguyoutside. I 've noticed your post has not received any review or reply so let me give you my insight. Whit this we have to consider different factors that could impact the final result of the exercise; to give you an example: differences in your speed and exertion levels may vary your numbers.

However if the difference is too recurrent, I recommend experimenting with how high you place the tracker on your wrist. When you're not exercising, wearing the tracker just above the wrist bone--as you would a watch--typically works fine. However, moving the tracker up a couple inches above the wristbone can be helpful during high-intensity exercises. The heart rate as you know have a great impact in the calories burned. Usually I've seen this when I play soccer. If I wear my tracker normally my BPM is lower and remain around 80 to 90 BPM. However if I roll my wristband a above my wristbone the heart rate accuracy improves to the point it reads between 120 to 140 BPM.

@justaguyoutside, when you logged a manual activity, note this will overrides the data that your tacker is reading or compensating the calories missed by your tracker. In the case you are not using your tracker make sure all the information is correct at the moment to logged. When I swam, almost the same distance to give you a comparison, it reads 603 calories. So in case the issue persist on a daily basis I would like to ask you a screenshots to have a closer look and give you a better solution.

See you around and keep me posted.

[Igorus]

Hi Robert,

Thanks for your reply and sorry for my late response.

For once, the problem here is not really with the heart rate readings, I have a pulse around 80-90 during that exercise so that's correct.

The problem is the calorie count for cycling (and perhaps) swimming with such low heart rate. The Surge assumes that while cycling slow I am burning the same amounts of calories as sitting, which is not true.

The Surge makes a jump from 1,6 kcal per minute to 4 kcal per minute, between cycling slow and cycling normal. That's an insane difference, almost 300%.

You would agree that you or me don't suddenly start burning 300% more calories while going just a bit faster?