diff --git a/Allow-running-indoors.md b/Allow-running-indoors.md
index a606fc9..902784d 100644
--- a/Allow-running-indoors.md
+++ b/Allow-running-indoors.md
@@ -2,6 +2,8 @@ Credit to TheXaman for posting this in the Simple Modifications Pokecommunity th
 
 This tutorial will allow the player to run on any map.
 
+Normally, the game checks the map header to see if the player is allowed to run on the map. All we need to do is remove that check.
+
 Edit [src/bike.c](../blob/master/src/bike.c):
 ```diff
  bool32 IsRunningDisallowed(u8 metatile)