#1
I started practicing shred on my LP instead of Strat because the sound suits it more, but after a few hours on the Les Paul I get cramps in my left hand between my middle and fourth finger.

I know some people shred on Les Pauls fine, but maybe I should stay away? I've been playing strats for four years without any cramps.
#2
you need to accustom your hand to the thickness of the LP. play it more. do more shreds so your hands would get stronger.
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