[DAVETHOMAS90]

Isn't the load on the fingers the same throughout the range of motion?

No not at all. It's much easier to hang in on the hold when you start with a kick. (I suspect that's because it takes about 0.6 seconds before the fingers reach 90% of maximal peak force (and about 2s to reach maximum peak force).)

Couldn't you achieve the same effect (e.g. 90% maximal peak force applied) by slowly lowering down onto the edge? The difference in difficulty between going from completely straight arm and bent then being about the shoulders, not fingers?

The force on the fingers will depend on the acceleration/deceleration of your body - i.e. upwards or lowering down.

If you pull with greater force, you will accelerate from rest - go up - more quickly. Conversely, yes, if you're trying to hold a small edge, you can reduce the load on your fingers by letting your body drop - say from a half-lock. Your body falls because you're trying to keep your body "up" with a force which is less than that of gravity acting on it.

In my earlier post, I wasn't highlighting the difference between starting bent/straight, though in practice there are certain mechanical difficulties which are harder to overcome from straight - hence the common "flick" when people start a one-arm from a straight hang. This flick requires additional acceleration to get the body past the weak spot, and hence a higher force. This is why "breaking the lock" is often a difficult sticking point on a hard problem.

[rodma]

The higher acceleration that I have witnessed is generally because people's arms/shoulder etc. Are not strong enough to do a one armer, so are writhing around to gain momentum, but this obviously requires greater maximal finger strength than just doing a smooth slow one armer.

I filmed an attempt on each arm this evening, as square on as I could on the small campus rung. I managed to move marginally upwards from a bent arm and that was it. Will post up the exciting footage tomorrow

[standard]

screw one armers.
let's see some static one arm hangs.

[slackline]

Some physicists or engineers will be able to give the correct answer but it seems like there'd be some complicated lever-arm differences between straight arm and slightly bent arm; so differences in force felt on fingers, elbow and shoulder?

Upon further reflection I realised that myself.

In biomechanics it seems the arm is a third-class lever (slides 25-26 on pg5) when the shoulder moves towards the hand (all the diagrams show a bicep curl but thats the same range of motion the arm is going through in a one-armer).

This presentation has some information on Biomechanics for Strength Training.

This one mentions that the mechanical advantage is greatest at 90 degrees (figure 13 pg 14).

[rodma]

Me flailing trying to just stay remotely face on

[jwi]

Isn't the load on the fingers the same throughout the range of motion?

No not at all. It's much easier to hang in on the hold when you start with a kick. (I suspect that's because it takes about 0.6 seconds before the fingers reach 90% of maximal peak force (and about 2s to reach maximum peak force).)

Couldn't you achieve the same effect (e.g. 90% maximal peak force applied) by slowly lowering down onto the edge? The difference in difficulty between going from completely straight arm and bent then being about the shoulders, not fingers?

Maybe. I just know from experience that  the only way I can achieve a "one arm hang" on a campus rung is by doing a one arm with kick start. There's no way I can do it hanging straight under the rung as for a normal two arm. And as we all know it is way easier to hang a rung (with two hands) on bent arms and leaning back a bit (I usually count that as the point of failure when finger boarding for time)

[Three Nine]

Me flailing trying to just stay remotely face on

Joble's done 8B+ and there's no fuckin way he can do that

[jwi]

To go back to the original question. One arming huge* edges is not a very reliable measure of finger strength.

* Huge in the context of an average Fb 8B

[haydn jones]

Thought I'd  add to the conversation. So about 2 1/2 years ago when i lived down south (lots of training and indoor climbing) i managed to one arm a small rung full crimp from slightly bent. I then managed my first 7C bens roof.

However earlier this spring i came close to climbing fat lip (8B) falling off the last moves i can assure you that there is exactly 0% chance of me hanging even the large rungs one arm these days.

[AMorris]

Me flailing trying to just stay remotely face on

effort
Can you do it with a half twist i.e. in your strongest position?

[rodma]

effort
Can you do it with a half twist i.e. in your strongest position?

sort of (say 2/3 to 3/4 of the full range of motion), but i clash with the bottom of the campus board, so the finish is physically impossible. in saying that, i didn't try last night, so I'll probably be proven wrong when i come to film it 

i thought I'd better just try and do the 1-armer i would like to be able to do (i.e. a proper one) and film that

same on the slot at the bottom of the beastmaker, which is much easier to hang.

[AMorris]

effort
Can you do it with a half twist i.e. in your strongest position?

sort of (say 2/3 to 3/4 of the full range of motion), but i clash with the bottom of the campus board, so the finish is physically impossible. in saying that, i didn't try last night, so I'll probably be proven wrong when i come to film it 

i thought I'd better just try and do the 1-armer i would like to be able to do (i.e. a proper one) and film that

same on the slot at the bottom of the beastmaker, which is much easier to hang.

fair enough! Yeah the low slot is easier than a campus rung especially if you nestle into the corner. I tend to do it with the half turn in the small edge since I find it easier to get under it and actually hang that way, it certainly adds a bit of spice if you stay front on and probably translates to actual climbing better.

[AMorris]

Here we are, for those who care. First time I have ever seen myself do this on video so I can pick holes in my form, its far from perfect but it gives me something to work on. Constructive criticism welcome, belligerent criticism is not.

[rodma]

Good effort.
That's as hard if not harder to hang than the small rung on the campus board. I was referring to the jug central crimp in the previous video posted when I said the small rung was harder. I hope you see what I mean about most climbers idea of a one armer being about half of a one armer and not in a very useful position.

[AMorris]

Good effort.
That's as hard if not harder to hang than the small rung on the campus board. I was referring to the jug central crimp in the previous video posted when I said the small rung was harder. I hope you see what I mean about most climbers idea of a one armer being about half of a one armer and not in a very useful position.

Yeah I think I am on about 3/4 here, I dont intend on starting from deadhang because of the potential damage but I can see a bit more lock at the top of the pull up available to me. I still think that this is pretty much useless except for the finger strength cos like you said, its a position you don't often get into whilst climbing, front on would be more useful. I will have to see how I fair on the low slot front on!

[rodma]

Have rewatched a few times and you need to look again at your footage to see what I'm getting at.

Starting from bent arm is fine. The first problem is that if I was to claim that I could do a two am pull-up, you would expect to see my feet off the ground prior to any upward movement starting. The second is that you are starting with your body at a half twist but don't seem to be able to maintain this (you rotate even further under ) and the third is that your shoulder finishes way below your hand.

This is why I filmed myself the way that I did, because I can look pretty convincing doing a "1 armer"  if you were to ignore thes details, as in I can walk up the the campus board grab the 1st rung in one hand and pull to the 4th, but that's not a one armer.

Work in progress for both of us

[dave]

This is like watching two prospective Rolls Royce owners whittling about whether their current top-of-the-line BMW and Lexus steeds aren't quite prestige enough.

[tomtom]

A one armer is of debatable benefit to climbing (some positives, some party trick elements) but translating the exercise to climbing - how often would you be expected to replicate that movement from a straight arm when climbing? Not often I suspect.. Doing 2 or 3 from a bent arm might be of more use than 1 perfect straight armed one...

Sorry if that's obvious and I'm missing the point.

[rodma]

A one armer is of debatable benefit to climbing (some positives, some party trick elements) but translating the exercise to climbing - how often would you be expected to replicate that movement from a straight arm when climbing? Not often I suspect.. Doing 2 or 3 from a bent arm might be of more use than 1 perfect straight armed one...

Sorry if that's obvious and I'm missing the point.

No that is perfectly the point. Overcoming any downwards movement to move upwards is way harder than kicking off the ground, no matter how gently.

As to how beneficial it is to be able to pull upwards one handed, the answer is it depends on the type of problems you are attempting

[Nibile]

A one armer is of debatable benefit to climbing (some positives, some party trick elements) but translating the exercise to climbing - how often would you be expected to replicate that movement from a straight arm when climbing? Not often I suspect..

It's not about the usefulness of an actual one armer that's relevant to climbing, it's the usefulness of having the potential. More power means more chances for success, ceteris paribus. But we all know this.
I remember the time when I was pure. I was young and my one arm training was face on.
Then at some point during this jouney into the unknown that we like to call "life", I got lost. Seduced and flattered by the sirens of the multiple one armers, I twisted my body and I twisted my dignity and honour. My mind was no more pure, it had bended and I had become the kind of human that Kant foresaw "for from such crooked wood as man is made of, nothing perfectly straight can be built."
I think that we could translate this into "for from such crooked pull as men do now, no chance on Hubble can be built."
Let's all be pure now.
Frangar non flectar.

[standard]

i still think "one arming" these holds is a poor way to measure "strong fingers".
Try just hanging them one handed. How long can you manage?

I can one arm them but not hang them for very long at all.

[rodma]

i still think "one arming" these holds is a poor way to measure "strong fingers".
Try just hanging them one handed. How long can you manage?

I can one arm them but not hang them for very long at all.

Video evidence

[petejh]

This is like watching two prospective Rolls Royce owners whittling about whether their current top-of-the-line BMW and Lexus steeds aren't quite prestige enough.

Quite an apt analogy, as the best way to get from A to B might be a Passat (efficiency), or a caterham super-7 (power-to-weight).

A rolls royce (one-armer) is an inefficient vanity project, but I wouldn't mind one.   

[tomtom]

This is like watching two prospective Rolls Royce owners whittling about whether their current top-of-the-line BMW and Lexus steeds aren't quite prestige enough.

Quite an apt analogy, as the best way to get from A to B might be a Passat (efficiency), or a caterham super-7 (power-to-weight).

A rolls royce (one-armer) is an inefficient vanity project, but I wouldn't mind one.   

:D

[abarro81]

Quite an apt analogy, as the best way to get from A to B might be a Passat (efficiency), or a caterham super-7 (power-to-weight).

Does that mean that my 1991 Nissan Micra suits my kneebaring predilection - no one will like you, you'll feel cheap dirty, but it'll get you where you need to go.

Overcoming any downwards movement to move upwards is way harder than kicking off the ground, no matter how gently.

This is true. I've often been able to do a '1-armer' comparable to that video posted above by AMorris (but using a bar/jug), but never in my life have I been able to go down at all and then re-engage and start moving upwards again. 

AMorris - my only critiquing is that you should not touch any fingerboards or campus boards for 1 year and climb on rock as much as humanly possible, climbing on set problems when that's not possible.