When you have a certain grip on the pick, do you switch the grip when feeling tired of feeling pain? For example, instead of holding the pick with your index finger and thumb, you hold it with your middle finger and thumb.

The reason being that you shouldn´t feel tired, and absolutely not feel any pain when playing. That is why you got the examine your technique and the way you practice so you are able to play things effortless. Things like how much to i tense up, how hard do i hold the pick etc, matters a whole lot.

Bottom-line: You shouldn´t have to, since feeling pain or feeling tired in the picking hand should not occur.
Fusion and jazz musician, a fan of most music.

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