This is an improvement over Socke68's sprint example, whats different? in Socke69's version if you press shift you will still move if you are not holding "W", and you can´t sprint backwards or sprint left or right. My version you only can sprint when you are holding "W" and shift, if you hold "S" and shift you will sprint backwards, but for some reason you can't go left and right when I tried it before it didn't work before but it's probably a bug anyway enjoy the example.
Example -->
www.gamemaker3d.com/player?pid=053828033246
Socke69's original one -->
www.gamemaker3d.com/player?pid=052900531784
ViraX and Tyler Broome's -->
www.gamemaker3d.com/player?pid=052710322013
(Edit)
OOPS I didn't know! the game didn't have source on! well now it's enabled