Sense is not tracking running / treadmill correctly (tracks less distance)

[Madecita]

Hello. I noticed that Sense is not tracking correctly treadmill and running, it tracks less distance than the real one. The best example is that I stepped into a treadmill where the speed is constant and it should have tracked 10km in the time I run but it tracked only 7km.

It also happens when running with GPS.

Please help.

[ManuFitbit]

It's good to see you around @Madecita.

Thank you for sharing the inquiry regarding your Sense. 

On a treadmill, normally, most of the people hold the bars/sides of the machine so if you're walking. Please, make sure to move your arms as if you were walking on the ground.

Also, keep in mind that when you're on the treadmill, you're not really moving forward but on the same place. In fact, there is no motion forward. You can also log this manually by following the steps here: How do I add, edit, or delete Fitbit data and activities?

Please, check your stride setting.  I'd recommend visiting the following link: How does my Fitbit device calculate my daily activity?. In this link, you will also get information about how to adjust your stride length on your Fitbit account. 

In addition, I'd suggest you check this article.

[Madecita]

Hello. I don't hold the bars of the treadmill, I'm used to running there so I don't do that.

So based on what you say maybe the treadmill activity should track different than running if it doesn't consider we're moving forward. I don't think it makes sense or is the idea to track manually, as I want it to track my heart rate, changes of speed if I change it, etc. It should really track correctly. 3 km less of difference is a lot.

I'll check the stride setting again, but I also get a lot of differences when running outside, based on the phone GPS vs my fitbit, Fitbit tracks less than other apps that use the phone GPS, and those apps track very similar between them. 

I hope you can review these issues soon. Thanks.