[shark]

I don't think this vital topic has been covered sufficiently 

Comparing notes with Probes earlier this week I can deadhang (2 arms natch) a small edge for 12 secs by dragging/open handing but can only half-crimp it for 4 secs whereas Probes reckoned it would be the other way round for him. When I think about it I reckon when climbing I would tend to open hand that sort of hold to move my feet around but would crimp it to make the move.

So what's going on here?
Is it actually more efficient to crank on a crimp or is it just that it feels better?
What flexors are being deployed for the different grip positions?
Are there mechanical advantages to the crimp vs frictional skin advantages to dragging/open handing ?
Is it beter to specifically train to correct anamolous grip strength differences or to focus on the strong/natural grip (if uninjured) ?
And most importantly which grip is the coolest? 

[nik at work]

Open handing is always coolest.

[Ru]

A guess, but it must be basically right:

Dragging: less muscle contraction, more reliance on friction and skin deformation, less tiring, need to maintain finger/ hand angle to hold otherwise friction lost, therefore best when hanging off hold with straighter arms.

Half crimp: more muscle contraction, more tiring, but can vary angle of hand to hold without changing angle of tips on the hold by bending fingers.

[shark]

Half crimp: more muscle contraction,

A good reason to train half-crimped?

[Ru]

Yes. I though that was the same conclusion Eva Lopez had come to? The only caveat is that I'm not sure how much half crimping trains the flexors of the first finger joint that are different to the flexors for the rest of the finger. I would have thought that if you want good first joint pocket strength you would be better training this open handed. I'm just making this up as I go along though. Still think I'm right.

[lagerstarfish]

Are there mechanical advantages to the crimp vs frictional skin advantages to dragging/open handing ?

there is the obvious advantage that crimping gets you a couple of inches higher up the rock - for horizontal edges it's just like having the hold a bit higher up the rock

for me it also puts my wrist in a better position when the hold is below shoulder hight

unfortunately I am scared of crimping

[tomtom]

For me its a grip issue... on grit I can often open hand even the teeniest of edges, but on lime (spit spit) I have to crimp a similar size edge otherwise my hand slips off...


PS, I'm scared of Lagers crimping too..

[Serpico]

Is it actually more efficient to crank on a crimp or is it just that it feels better?

Open handing works best when you're pulling down on a hold, when a hold starts getting near shoulder height  you're starting to pull out on it more, a crimp can pivot on the hold because the fingertips are fixed (by the thumb usually) closer to the wrist.

What flexors are being deployed for the different grip positions?

The FDP-FDS tendon- force ratio for the crimp grip is 1.75:1
The FDP-FDS tendon-force ratio for the open hand grip is 0.88:1
Laurent Vigourouxa,
,Franck Quainea,Annick Labarre-Vilab,Franc-ois Moutetc 2005
In addition there is significant contribution from the wrist extensors in the crimp grip to extend the wrist which pre loads the finger flexors and brings the fingers closer to the wrist reducing the moment arm.

Are there mechanical advantages to the crimp vs frictional skin advantages to dragging/open handing ?

See above for mechanical advantages of crimping. For open handing Lopez and Bourne found in separate studies that open handed finger strength on small holds was strongly related to the amount of flesh at the finger tip deforming to the edge.

Is it better to specifically train to correct anomalous grip strength differences or to focus on the strong/natural grip (if uninjured) ?

Train to correct grip strength differences, and then according to Lopez train half crimp because it's a pure muscle strength grip - not limited by finger tip flesh/skin thickness.

Another thing to consider is the study by Andreas Schweizer, MD 2001, that showed that after 50 repetitions of a crimp grip bowstringing in the A2 pulley increased by 30%, increasing the moment arm and so increasing finger strength by a small percentage. It's possible that with repeated exercise this stretch could increase over time.

[shark]

Cheers Serps although I only understood the first and third answer

What is the moment arm ?
Can you train wrist extensors seperately ?
Isn't bowstringing a bad thing ?
Can you explain what the tendon force ratio means...

[Serpico]

Cheers Serps although I only understood the first and third answer

What is the moment arm ?
Can you train wrist extensors seperately ?
Isn't bowstringing a bad thing ?
Can you explain what the tendon force ratio means...

Moment arm = moment of force, think levers and leverage.
You can train anything separately but it's better if you train it with the specificity of the thing you want to improve at.
Bowstringing is only a bad thing if you're bowstringing because of a pulley rupture.
The tendon force ratio is the ratio of forces transmitted by the two main finger flexors. As the ratio changes so does the contribution of the two tendons and the muscles which they're attached to.

[shark]

Thanks

[i.munro]

You can train anything separately but it's better if you train it with the specificity of the thing you want to improve at.

Interesting comment when discussing FBing 

Any thoughts on how if/how much to FB instead of bouldering where there's a choice.

[Sasquatch]

Fnatastic - Thanks Shark for asking and thanks Serpico for the solid answer.

So parlaying the information so far into simple functional terms.  Generally speaking, the harder the move from a hold, the better it is to crimp.  The harder to hang a specific hold, the better to open hand. Do I have that right? 

Now what about comparing this for different types of climbing - Steep overhangs vs. vertical/slab? Seems like this changes the moment arm pretty significantly and may change the above generality. 

What about the difference for crimping and openhand/dragging in dynamic vs. static movement? 

[Serpico]

Fnatastic - Thanks Shark for asking and thanks Serpico for the solid answer.

So parlaying the information so far into simple functional terms.  Generally speaking, the harder the move from a hold, the better it is to crimp.  The harder to hang a specific hold, the better to open hand. Do I have that right? 

For me it's easier to hang beneath a hold open handed than crimped. When it comes to moving off a hold I find it doesn't make too much difference if I'm moving dynamically, but if I have to lock deep then I have to crimp. When open handing your palm is parallel to the rock, when you're locking lower than shoulder height the wrist angle makes this difficult to maintain.
When the going gets tough a crimp for me always feels the most secure, probably because I've wrapped my thumb over.

[Serpico]

You can train anything separately but it's better if you train it with the specificity of the thing you want to improve at.

Interesting comment when discussing FBing 

Any thoughts on how if/how much to FB instead of bouldering where there's a choice.

There's degrees of specificity, isolating the wrist contraction bit of a deadhang really is isolation training.
I wouldn't consider FB instead of bouldering unless you were a full time climber. FB is something you can add in before or after your session or at home.

[Sasquatch]

Interesting comment when discussing FBing 

Any thoughts on how if/how much to FB instead of bouldering where there's a choice.

There's degrees of specificity, isolating the wrist contraction bit of a deadhang really is isolation training.
I wouldn't consider FB instead of bouldering unless you were a full time climber. FB is something you can add in before or after your session or at home.

If it's a question doing only one of the two, then that would be dependant on the individual and their background and weaknesses. 

[abarro81]

If it's actually a hard move/poor hold this conversation is probably irrelevant - you hold the hold however you can do the move easiest. 

[nik at work]

That as it may be, we all know that open-handing is coolest.

[Sasquatch]

That as it may be, we all know that open-handing is coolest.