Please watch the video before downloading otherwise the exercises won't make sense 😁
The biggest problem people have when it comes to alternate picking quickly is they get mixed up on the string crossings... (Down up down, Up down up...)
These exercises single out those motions and work to clean them up and speed them up without muscle strain.
Inside the tab / video:
Crossing between two strings (up and down stroke)
Crossing between all six strings
Duplicate picking (down down up, up up down)
All of these are common picking "problems" you can run into in your playing!