It's not a good idea, 'cause you're actually training them on chest and back days too
I have read that some guys hit a bodypart twice per week if it lagging. For instance my shoulders are a little more underdeveloped in comparison to the rest of my body. Would it be recommended to hit these twice per week?
It's not a good idea, 'cause you're actually training them on chest and back days too

add a exercise or two on chest and back days just make sure pick your exercises carefuly.
Probably mental.
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