How to reset my step length? I have had a new iPhone SE for a few weeks. It works fine, but in the "Health" app, my step length is approximately 0.6 m (1000 steps give a distance of 600 meters), which seems wrong (I used to have around 0.8 m with my previous phone). I also checked with the distance on my companion's iPhone : my iPhone correctly measures steps, but not distances.  

Is there any way to reset this ?

BTW : yes, I have allowed the "Motion Calibration &amp; Distance" option in the "Privacy" setting.
Unfortunately Apple does not provide this option in the health app. 

There is an app that does though called Fitbit which tracks your steps and you can input your step length. This feature does not require a tracker.

Link to app in AppStore:
Fitbit by Fitbit, Inc. https://itunes.apple.com/gb/app/fitbit/id462638897?mt=8