What is that sh*t you smoke?)))
7mph??? Maybe km/h? More less common walking speed for a regular person is around 7km/h(4,35mph), same for running speed, not people never break 20km/h(12,5mph) record specially if we are talking of 1-5km runs, not a 100m sprint. I would actually suggest make speed differentiate depending on your stamina, so you slow your pace when getting tired.