that is shred exercise. so for tremolo picking, just pick a chord as fast as you and for as long as you can. that is. learn some chord changes and negura bunget songs, 3 metallica songs to develop right hand with downstrokes(blackened and master of puppets) only, or chugging (disposable heroes), some 1234, but definitely not for shred and extreme speeds, some iced earth for gallops and the damage inc bridge riff to develop rhytmic coordination and right hand stamina (masturbation works too for this).
do this and you will be krieg