According to wikipedia, normal walking speed for most people is about 5km/h. But in the game it's not possible to set such speed. In summer, when I used to play pokemon go legit, I used to walk at about 6km/h. Please add an intermediate speed between the current walking and jogging, to be more human like. And also add some randomness to the walking speed, no human will ever walk at exact constant speed.
This is a great suggestion and has now been added to the list of ideas to be reviewed by our dev team! Thank you again for your suggestion and keep an eye on updates for more information as new patches comes out for PokeFarmer