creating or closing distance

In self defence

we are either trying to create distance from an attacker or close the distance on attacker

create distance
 moving away or back to give you space away from attacker, allowing you to run, escape, talk even grab improvised weapons

close distance
 step in or crash into attacker getting you inside the striking power zone and allow you to control or do much damage with elbows and knees

either way you have to move quickly either further away or closer to your attacker