When palm muting and playing fast power chords, is it best to strum them all down or alternate? I can't seem to strum up when I palm mute but with some songs I've attempted I really can't get the speed up when I'm strumming them all down.
practice and you can learn to do upstrokes while palm muting.
I have this same problem, actually.. I probably spend a good half hour or so everytime I'm playing just palm muting and alternate picking, but I never make any progress. A lot of songs require that too.
Sometimes you can tell by listening to the song you can tell. If it's not too "fast" you can play all downstokes. But at a certain point that's not possible. Learning both is never a bad idea.