Grip for the Pull | Mark Rippetoe

[stef]

"It has come to my attention that some of you people are reluctant to move to the hook or alternate grip as your deadlifts get heavier. You apparently think you'll be giving up grip strength if you do... "

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[Stefan Rott]

This.
I switched to the hookgrip at 137.5 Kg last week, 135 were doable doh, but I noticed -as you said- a form issue with my back extension due to too much concentrating on my slippery grip. I use chalk and I really wanted to manage doh 'till 150 Kg, but hey... That spiky pain in my thumbs feels like a wake up call to stay alert to use correct form, so it works for me.