Question regarding deadlift grip/proprioception

[Luke Evans]

Coach, I've got a question about deadlift grip.

I was lifting with a friend and they asked why alternating your grip makes it easier to pull heavier weight. At the time, this was the only answer I could give them because I couldn't recall the details from SS. Given that neither I nor my friend are five years old, I wanted to find a more satisfactory answer.

I went back and found the following in SS 3rd Ed, pg. 101: "The back will not pull off the floor what the hands cannot hold, due to proprioceptive feedback that tells the back that the weight is too heavy. When the grip is flipped and the hands don't slip as the load increases off the floor, the back doesn't receive the signal that makes it stop the pull."

I suppose my question is twofold.

Firstly, what is it about an alternated grip that makes the hands not slip?

Secondly, could you explain a little more about the signal that stops the pull? I don't understand the mechanics in play here and my googling thus far has been unsuccessful.

I think my misunderstanding stems from this: the back won't pull what the hands cannot hold, but the hands can hold the weight. Your grip strength doesn't somehow increase when you alternate your grip, right?

I'm sorry if this is a foolish question, but I can't get my head around it. Thanks for your time.

[lionheartck]

The answer to the first one is probably that the bar will roll out of your grip as it fails. The bar, being too heavy for your grip, straightens out your fingers and rolls toward the tips. With your hands alternated, the bar would have to roll in both directions to open your grip.

[Rich Rowe]

Hey Luke,

Lionheart is right about switching the grip in relation to the bar rolling out of your hands - to roll out of one hand it is rolling *into* the other hand, if they are facing alternate directions - the net torque on the bar is thus zero.

For the second part, you are right: your grip doesn't actually increase in strength when you alternate hands (as far as I know) but the bar will not roll now (as previously understood). The hands - especially the fingertips - have a great number of what are known as bulbous corpuscles (or Ruffini Corpuscles) and these are long thin bundles of nerve endings like little cigars lying parallel with the surface of the skin. They are very sensitive to the feeling of shear/stretch and can detect whether an object is slipping out of the grip of the hand. If your nerves detect this kind of slippage, you won't be able to apply maximum force. (They're also found near joints and give accurate feedback to the angle of the joint).

I don't know the whole story all the way back to the brain and down to the muscles, but the Ruffini corpuscles are where the 'slipping alert' is issued from.

Hope that helps!