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/ distribution of load between feet and hands

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David Coley - on 02 Jan 2018
Hi,
we all know we should place as much of our weight as possible on our feet, not hands, but does anyone know of any published research on the split of load between the hands and feet, particularly as a function of how well the climber climbs and the angle of the rock?

If the answer to the above is a no, do any budding sport science students fancy studying this as a dissertation? Or just something to add a paper to your CV? If part of a dissertation, this would need to fit into the arrangements of your institution, but I'm guessing this would be possible (I'm an academic).

I have an idea of how to complete a reasonable measurement and have bought the equipment to do so (a 100kg spring balance, some plywood, a bolt and a climbing hold).

This is my publication record - nothing about sports science, but you can see that I publish at a reasonable rate:
https://researchportal.bath.ac.uk/en/persons/david-coley/publications/

All the best,

D.
5
Gordon Stainforth - on 02 Jan 2018
In reply to David Coley:

You ask an interesting climbing question on this climbing website, free of all moral and political implications, and some complete wally (probably one of the many bitter virtual non-climbers who lurk here) gives you a 'dislike'. What on earth is this website for if you can't ask an interesting climbing question like this without being sneered at?

PS. You also have the guts to post under (what I suspect is) your real name.

Cheers, and Happy New Year!
Post edited at 17:20
13
jezb1 - on 02 Jan 2018
In reply to David Coley:

Haven’t Lattice looked in to this? Remember reading something about it, but could well be wrong.
Tyler - on 02 Jan 2018
In reply to Gordon Stainforth:

I didn't dislike but it is a daft question, there are too many variables to get any meaningful results, e.g. Foot holds relative to hands (are they up close to hands or low down, off to the side) , footholds relative to each other (staggered, is there one or two) before we get into size and positivity of hold. The split will differ with every move even moves if the same grade on the same angle knot to mention on the efficiencies and relative skills of the climber being tested).
4
Gordon Stainforth - on 02 Jan 2018
In reply to Tyler:

I'm not at all convinced it's a daft question. I saw, years ago, some article which looked quite scientific (or was it in one of Long's books?) that gave the proportion of loading of hands and feet for different angles of rock. What I remember as being rather startling was that, even on very overhanging rock, the feet are still taking most of the weight and doing most of the work. That is, with climbers who climb very well.
2
John Kettle - on 02 Jan 2018
In reply to David Coley:
Check the Beta Angel website for links to the majority of climbing research.
It's a great question and one I'd love to see explored on a set route to quantify movement economy with load cell holds etc. If only I didn't have a mortgage, family to feed etc..
alx on 02 Jan 2018
In reply to David Coley:
Hi David

It is an interesting question however I feel loading of the limbs based on wall angle lacks the nuance to make this research question meaningful. Would it not be more about the system as a whole, from the shape and angle of the handholds, through limb length and morphology, overall weight distribution across the individuals body through to the type of shoes and the shape/angle of the footholds.

You could used a canned system using set holds on a tipping board with a set number of people to get a result, but I fear you may come under fire for your setup not being representative of actual climbing.

I think this area does need to be explored more so people are not stuck in the rut of thinking skinny people should just sport climb, muscly people should just boulder and the tall and/or heavy should give up aspiring to climb hard grades because they are the wrong build.
Post edited at 18:27
alx on 02 Jan 2018
In reply to David Coley:

I should add in the space between the holds and position is also key factor
stp - on 02 Jan 2018
In reply to David Coley:

It might be interesting to find out but totally impractical to measure. If you could get a climbing wall where every hold could measure the amount of weight it bears and for how long and then push all the data into a computer for analysis you might get somewhere.

But as you said it's better to place as much weight through the feet - well most of the time. Sometimes it's not though. For some climbers it might be better to just campus a move if they've got the strength. For a weaker climber though they may have to keep their feet on. Does that make them a better climber? I don't think so. They're just a different climber with a different physiology so they have to do the move differently.

There are so many variables to consider with climbing. Unlike other sports every single move is different. Added to that every person is different. Some may have strong legs and core, others may have really strong fingers and lock off strength. Add to that differences in height, arm span and flexibility and it's starts to get extremely complicated. The best or most efficient way to do something won't be the same for everyone.
David Coley - on 02 Jan 2018
Thanks everyone for your comments, all great stuff.

I get the point that climbing is complex and the exact form and distribution of the holds would be important for the best ratio for any problem. (I also climb, badly: https://www.amazon.co.uk/High-Advanced-Multi-Pitch-Climbing-ebook/dp/B00UJG9DH6 )

However, that is not the question I'm trying to answer. The question is, whether for any set of holds and angle of wall the ratio is DIFFERENT for someone who climbs 8a than someone who climbs 7a, or 6a. Then, if it is different, is it linear w.r.t. max grade climbed, or not. To me this seems answerable with one foothold bolted to a spring balance and a bouldering wall. Then asking a large number of climber to hang/semi-rest on a variety of the surrounding holds. And measuring the weight of each climber to give the other half of the ratio.

All thoughts welcome - and don't worry, I have a reasonably thick skin, and I hope a good sense of humour.




1
john arran - on 02 Jan 2018
In reply to David Coley:

To me it seems pretty obvious that there are more and less efficient ways to distribute your weight across the same set of holds, and the more efficient ways will probably, but not necessarily, be used by more proficient climbers. I'm guessing there would be a correlation between weight distribution pattern and grade climbed, but the data is likely to be quite noisy due to over-strong climbers finding it easier to move more quickly but less efficiently through a sequence.

I'd personally be interested in knowing quite how optimal my movement was in terms of minimising finger weighting on any hold or holds, as to me the techniques involved in minimising this are at the core of what I see as good technique.
MischaHY - on 02 Jan 2018
In reply to jezb1:
Yeah they did some testing with load sensors or similar attached to holds - one input they managed to glean was that people who climb in the frogged position (hips in legs splayed wider) i.e. many strong women are actually gaining something like 10-20% weight decrease on the hands from the stance which led to moves being easier. Properly interesting and definitely something to make the naysayers look a bit silly.
Post edited at 22:48
Tyler - on 02 Jan 2018
In reply to MischaHY:
> Yeah they did some testing with load sensors or similar attached to holds - one input they managed to glean was that people who climb in the frogged position (hips in legs splayed wider) i.e. many strong women are actually gaining something like 10-20% weight decrease on the hands from the stance which led to moves being easier. Properly interesting and definitely something to make the naysayers look a bit silly.

What? So getting your hips closer to the rock means you an get more weight over your feet and reduce the amount weight on your arms? As one of the naysayers I certainly feel a bit silly now as that's not obvious at all.
Post edited at 23:06
1
Lord_ash2000 - on 02 Jan 2018
In reply to David Coley:

It would be an interesting test to carry out, and if anyone does it I'd be interested in the resulted yielded. However, I think hanging from set holds in a rest position with one foot on a hold won't yield much variation between the different climber skill sets.

The reason being that for most stances there isn't much skill required to hold onto two jugs and stand on a typical foothold below you, so a 6b climber would likey put just as much weight on their leg as an 8b climber.

You might get some difference if the foothold was a tiny screw on though because that would require some skill to put a lot of weight through the toe, but you'd want to ensure they all wore the comparable rock boots though. Another option would be to have the holds located so they had to do a really high foot and rock over onto the foothold, as again that would require more skill to rock over and transfer a lot of weight onto the foot.

The best option would be set a route or long boulder problem of say 6b with set weight measuring footholds to use. Include a few technical or unusual moves and then see what the results are like from a 6b climber climbing close to their max and an 8a climber cruising.
David Coley - on 03 Jan 2018
In reply to John Kettle:

Hi
I had a quick look at the papers on that site and didn't find anything, nor in the refs of the papers (but I haven't looked at everything).

I think if one was to look at just the quested I proposed, this should be relatively easy.
mik82 - on 03 Jan 2018
In reply to Tyler:
> What? So getting your hips closer to the rock means you an get more weight over your feet and reduce the amount weight on your arms? As one of the naysayers I certainly feel a bit silly now as that's not obvious at all.

Getting your hips close in definitely makes it easier on your hands. It doesn't seem intuitive, but twisting hips into the rock on steep sections makes a noticeable difference.

If you think about it, when your hips are hanging out below your arms on an overhang, your centre of mass will be closer in a horizontal direction towards them. There'll hence be a higher vertical force component acting on your hands to pull them off.
Post edited at 10:56
jkarran - on 03 Jan 2018
In reply to David Coley:

> However, that is not the question I'm trying to answer. The question is, whether for any set of holds and angle of wall the ratio is DIFFERENT for someone who climbs 8a than someone who climbs 7a, or 6a. Then, if it is different, is it linear w.r.t. max grade climbed, or not. To me this seems answerable with one foothold bolted to a spring balance and a bouldering wall. Then asking a large number of climber to hang/semi-rest on a variety of the surrounding holds. And measuring the weight of each climber to give the other half of the ratio.

I think you'd want to instrument both footholds and you'd need a mechanism designed to isolate the vertical (weight) component of the force without binding up under horizontal loads (or torque) if that's really what you're interested in and you'll need to damp/average the reading, it'll be quite unstable and hard to read from a spring gauge introducing potential for measurement error into what will already be a (likely quite small) noisy data set. Also, as ever, what qualifies as 'max grade': OS, RP, UK or Euro, 1off or 30% success rate in 3 tries, this year or a decade ago...? I think you'd want to test actual climbing performance in the same session you test the hand/foot load ratio to clean the data up a bit more, perhaps with a progressively more difficult circuit board at an angle representative of the angles you test the loading ratio at.
jk
Post edited at 11:07
MischaHY - on 03 Jan 2018
In reply to Tyler:

It's always worth proving things so that we know what works. Facts and evidence are the foundation of a scientific approach to training and sport, which is what this thread is about. This was in comparison to another technique (drop knees maybe? Slips the mind.

With respect surely you could contribute to this thread without resorting to sarcasm.
paul_the_northerner - on 03 Jan 2018
In reply to David Coley:

it would be very interesting if a moon board was rigged up with pressure sensitive holds, this way a number of problems could be analysed across a broad grade range.

who knows, perhaps it could be the future of training! a 'smart' moonboard would certainly be an interesting product to compare against other climbers.
Robert Durran - on 03 Jan 2018
In reply to Tyler:

> What? So getting your hips closer to the rock means you an get more weight over your feet and reduce the amount weight on your arms? As one of the naysayers I certainly feel a bit silly now as that's not obvious at all.

Simple moments.
JLS on 03 Jan 2018
In reply to David Coley:
>"The question is, whether for any set of holds and angle of wall the ratio is DIFFERENT for someone who climbs 8a than someone who climbs 7a, or 6a."

I'd hypothesize that there is too much variation in proportions and relative position of center of gravity in climbers to correlate grade climbed to a weight distribution ratio.

With fixed spacing between foot holds and hand holds: A tall 6a climber with low upper body muscle bulk and perhaps a fat @rse would have a lower CG and have the ability to move that CG closer to the foot holds giving himself a good ratio, while a short lean 8a climber with high upper body muscle and high CG is stuck spanned between your holds unable to ship any of the weight towards the feet.

If we looked at 6a and 8a climbers both of equal height then we might start to better use of core strength in the 8a climber to move weight towards the feet but if the 8a climber has a high CG to start with due to body composition then again his efforts might still not yield a better ratio than the 6a climber.

So, in short, test away but I'd be surprised if it yielded any meaningful results...

Edit: Maybe if setting of the spacing between foot holds and hand holds was adjusted as a function of climber height then some of these difficulties would go away but there would still be ape index variation to consider...
Post edited at 13:41
David Coley - on 03 Jan 2018
In reply to JLS:

> I'd hypothesize that there is too much variation in proportions and relative position of center of gravity in climbers to correlate grade climbed to a weight distribution ratio.

I was planing to control for this by binning the data w.r.t. weight and height of climber.
David Coley - on 03 Jan 2018
In reply to jkarran:

> I think you'd want to instrument both footholds and you'd need a mechanism designed to isolate the vertical (weight) component of the force without binding up under horizontal loads (or torque) if that's really what you're interested in and you'll need to damp/average the reading, it'll be quite unstable and hard to read from a spring gauge introducing potential for measurement error into what will already be a (likely quite small) noisy data set. Also, as ever, what qualifies as 'max grade': OS, RP, UK or Euro, 1off or 30% success rate in 3 tries, this year or a decade ago...? I think you'd want to test actual climbing performance in the same session you test the hand/foot load ratio to clean the data up a bit more, perhaps with a progressively more difficult circuit board at an angle representative of the angles you test the loading ratio at.

Hi
I'm hoping this can all be worked around, the damping will be interesting, although a spring balance is quite damped. I might record the scale with a go-pro over say 15seconds per position, then average - does that sound reasonable.

I was hoping the grade would be self reported. I guess I would use something like their max indoor bouldering, onsite sport and sport redpoint - all indoors and over the last 12 months. But open to suggestions.


JLS on 03 Jan 2018
In reply to David Coley:
Sounds like you'd need a big sample size (i.e. in the hundreds) to do that meaningfully.

I suppose you could incentivise by offering cake to those that take part but that would further diminish the chances of the sample containing very many 8a climbers.
Post edited at 14:31
David Coley - on 03 Jan 2018
In reply to JLS:


> So, in short, test away but I'd be surprised if it yielded any meaningful results...

By that do you mean (i.e. you predict) the ratio will be the same regardless of grade, when averaged over a lot of climbers and positions held; or that the noise will be too great to gather good data?

I can only see two sources of noise
1. damping - i.e. people keep bouncing up and down on the foot hold.
2. the person-to-person answers are so variable that they dominate over the question of which grade people climb.

I don't think (2) is a killer, as it would in itself be an interesting result, in essence it is the null hypothesis.

As a I have a bouldering wall at my house I'm hoping to find out the answer to (1) quite quickly.
David Coley - on 03 Jan 2018
In reply to JLS:

> Sounds like you'd need a big sample size (i.e. in the hundreds) to do that meaningfully.

> I suppose you could incentivise by offering cake to those that take part but that would further diminish the chances of the sample containing very many 8a climbers.


I think cake is a great idea! Thanks.

I will use a power calculation based on the standard deviation obtained during a quick pilot study to set the sample size.
WB on 03 Jan 2018
In reply to David Coley:

Hi
In my opinion you would not get a good answer, or one from which you could identify a relationship. Like someone has said, there are too many variables.
E.g. If you had a board at 45 degrees (probably the best angle for the test, as any less would bias the feet and any more would bias the arms) with a couple of hand holds and a couple of footholds. The 6a climber might not have much weight on the footholds as they do not have the strength and the 8a climber might not have much weight on the footholds, as they don’t need them to be able use the handholds. You could inaccurately conclude weight distribution was the same irrespective of the grade.

You could get all climbers to push as hard as possible on the footholds to measure their potential to distribute weight, but this is not what you are asking.

The next question you are asking is what size (“variety of surrounding”) holds can different climbers use, and is this related to grade. (I do not know, but) I am sure studies have been done on what grade people climb and what size holds can they hang – there is probably enough data in fit club to draw some conclusions – mainly there will be some relationship, but nothing you can relate to all climbers.

Finally I am not sure what you would conclude from the results. Most climbers understand using their feet well is critical to efficient climbing. But maximising weight distribution between your hands and feet well does not necessarily mean efficient movement. The critical point being climbing is about movement, not staying still, so better weight distribution does not equal better climber.

What might be interesting is to work out how much weight would you have to take off a Fr6a climber to allow them a Fr8a climber. I.e. I think there is a basic measure of campus moves equating roughly to a Fr8a. If you then took a Fr 6a climber and used the weighted balance foot holds to assist, you could measure the amount of weight over time required to meet the same target. It might then be possible to say if a Fr6a climber was able to remove x amount of weight from their arms through more efficient weight distribution then they could possibly climb 8a.
JLS on 03 Jan 2018
In reply to David Coley:

>"By that do you mean (i.e. you predict) the ratio will be the same regardless of grade, when averaged over a lot of climbers and positions held"

^^^^this

Yes, my gut feeling is that there will be no correlation between grade climbed and load distribution ratio.
I suppose if you make the "position held" complex i.e. your left foot needs to go somewhere near your right ear then yes, your better climber might come out in top. However, if we are talking about two good level foot holds and juggy hand holds at shoulder height then I'd guess the physics will trump skill.
jkarran - on 03 Jan 2018
In reply to David Coley:

It'd be interesting to log applied forces during movement but I think realistically a static 'resting' set-up is more practical.

If it were me doing the experiment (as a non academic engineer) I'd make a small overhanging (so very poor holds are available) foot board with a few differing holds on it supported by a load cell arranged to only log the vertical force component. Above that but not loading it add a tilting board with a few hand holds of varied types and heights. Set a few 'rest position' problems of varied difficulty then log the results for several problems for each climber.

I still think ideally you'd measure capability rather than having it self reported, grades, opinions of what 'counts' and day-to-day performance vary so much especially indoors and with fatigue/injury/conditions.
Tyler - on 03 Jan 2018
In reply to MischaHY:

> It's always worth proving things so that we know what works. Facts and evidence are the foundation of a scientific approach to training and sport, which is what this thread is about.
You could prove it with GCSE physics and a simple diagram if you think evidence is required.

> This was in comparison to another technique (drop knees maybe? Slips the mind.
The OP is trying to compare the efficacy of climbers of different ability on the same move not comparing the efficacy of different stances/moves.

> With respect surely you could contribute to this thread without resorting to sarcasm.
With rather less respect, I'm capable of both.
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trouserburp - on 03 Jan 2018
In reply to David Coley:

The question is, whether for any set of holds and angle of wall the ratio is DIFFERENT for someone who climbs 8a than someone who climbs 7a, or 6a. Then, if it is different, is it linear w.r.t. max grade climbed, or not. To me this seems answerable with one foothold bolted to a spring balance and a bouldering wall. Then asking a large number of climber to hang/semi-rest on a variety of the surrounding holds. And measuring the weight of each climber to give the other half of the ratio.

If they're hanging off exactly the same holds then this is just a test of core strength and toe-hooking proficiency/shoe shape

Is your question, do better climbers channel more weight through the footholds? Almost certainly, due to better technique and core strength. Not sure you'll learn anything useful by measuring how much
LeeWood - on 03 Jan 2018
In reply to David Coley:

what the devil would anyone do with such results ? speculation !?

what might be of further interest (nevertheless speculative ) is to know what happens for different coefficients of friction on the footholds - eg. different rocktypes and degrees of polish require +/`- handgrip in opposition - this could be measured with greater objectivity I reckon
David Coley - on 03 Jan 2018
In reply to LeeWood:

> what the devil would anyone do with such results ? speculation !?

Hi,
1. if the result is that there is no difference between good and bad climbers, that I think would be very surprising to many above; although not to others above. Hence, the result would be of interest of itself, as it shows which of these thoughts is correct.

2. if the result is that there is a difference (with good climbers placing more weight on their feet), I would be interested to see if by giving real time visual feedback via a display to those placing less weight on their feet, might help them place more weight on their feet. This would then suggest one reason that less good climbers place less weight on their feet (assuming they do) is not core strength, but not being able to sense it.
Paz - on 03 Jan 2018
In reply to David Coley:
On a good undercut, on a slightly overhanging wall, the total vertical load on both your feet might be more than bodyweight. What sort of holds and position do you have in mind?

How are you going to measure the frictional force and normal reactive force separately, or are you not bothered about that?

Wouldn't a modern load cell or strain gauge set up do the job a lot better than a naive spring balance?

https://en.wikipedia.org/wiki/Load_cell
https://uk.rs-online.com/web/c/automation-control-gear/sensors-transducers/load-cells/
Post edited at 17:19
David Coley - on 03 Jan 2018
Thanks Paz,

> On a good undercut, on a slightly overhanging wall, the total vertical load on both your feet might be more than bodyweight. What sort of holds and position do you have in mind?

I wasn't thinking undercuts, just mix of short and long reaches, inside and outside edges.


> How are you going to measure the frictional force and normal reactive force separately, or are you not bothered about that?

I wasn't going to try to. As this is in essence just a comparison between two groups of climbers.


> Wouldn't a modern load cell or strain gauge set up do the job a lot better than a naive spring balance?

Quiet possibly. Might you be willing to draw up something I could implement, please?
Paz - on 03 Jan 2018
In reply to David Coley:

Cheers David. I thought it was worth asking about the different force components, because I think one of the attributes of a technically good climber is the ability to generate and use more frictional force than a less technically good climber. And the angle of the spring balance will move, so it will only ever measure the total magnitude of the force (and no shear force), and only then when it's in tension.

Measuring the force on an indoor hold too, will not tell you anything about how much crack climbing technique someone has - if you could measure the force state of the crack, you've got too separate planes to measure the state of play of the `whole '`hold' (e.g. a hand jam). Even outside of cracks, I think being able to exploiting and use opposing forces, e.g. palming off and pushing, stemming and weird groove stuff, is a clear sign the climber is technically better than someone who can't do so. The forces in this situation are about getting more weight on your feet, but the force on the hand hold isn't necessarily in tension, especially if you're pushing off it. Similarly you can't tell how good at mantelshelves someone is by simply measuring the forces on an indoor bolt on.

I would beware of making the boulder problem or set of holds you use too simple - some climbing training problems are called basic problems, and are chosen deliberately because they are so simple, it's not possible to make them any easier using technique, you just have to use strength or power (brute force!). Which is fine if you're deliberately training strength or power. But less useful I would have thought, for measuring technique on, unless someone is incredibly gifted.

On the other hand, technical problems can be very body shape and body size specific, especially knee bars, but also if Egyptians aren't possible for someone with too short or too long legs. Cutting your feet off might occasionally be the technically best way forward too - or even a problem might actually be easier for some people using a figure 4, in which case there'd be no load at all on the foot hold, or if previous moves have exhausted one body part, using a different technique - that is less efficient for that move in isolation - but which puts less load on the tired limb (most likely an arm) than other options, is quite an advanced redpoint tactic for long routes.

In a way you're trying to deliberately measure how good at `'cheating' on the problem a climber is, while remaining within the rules, so if you're making them try to flash it, the beta you give them (experimental instructions to the test subject) is just as important too, e.g. if they don't spot they can bicycle a foot hold (toe hook underneath a protruding foot hold they're standing on with the other foot, and pull in on it using friction from the opposing forces - excellent technique in my opinion where it's helpful), but you someone else receives a hint, e.g. from a previous climber, then you need to junk those data points as those climbers had more information.

So personally I'd not bother enforcing climbing competition onsight rules, and would intend just test plain redpoint/send ability, and give everyone the same info/beta, as much as is reasonable, and answer all their questions.

For the boulder problems you're describing, it sounds like a lot of this will simply come down to body tension, and there's a raw strength component to that (to have it) as well as a technique (to know how to use it).

Another aspect is whether the problem requires movement, or just involves holding a stationary position (is isometric). You're only measuring static forces, which is fine, - but forcing someone to climb statically makes the test a bit eliminate for a test of technique. Quite often the forces on a hold can be reduced by climbing dynamically, e.g. as a dyno, or even as chain of dynos (first generation -> second gen -> ... -> God-level Dawes stuff) and sometimes a hold can be avoided entirely. And then if it is static, how long do you require a climber to hold a position for - if there is a knee bar then certain people could stay there for ages, in what is a rest position -for them, that they created, or were able to find- in which case I would say it doesn't matter what the scientific measurements of force are saying, that climber clearly has excellent technique.

There should be designs for experimental rigs using load cells out there in the literature - this instrumented wireless connected climbing hold looks ideal: https://www.researchgate.net/publication/259400674_A_Climbing_Hold_With_an_Integrated_Three_Dimensio...
It doesn't look like that's just a product on the market, but as long as three load cells are mounted with each perpendicular (orthogonal) to the other two, they'll capture everything. I'd love to design something, cheers, but it's not really my area of expertise.

Wayne S - on 03 Jan 2018
In reply to David Coley:

Hi, Interesting thread, though I am not sure that a snap shot of weight on holds tells very much. What I mean is this: I think the interaction is pretty complicated as in that low force on hand holds might suggest that climber A is proficient at finding rests, but climber B might apply huge forces to the same hand holds briefly as part of a more dynamic climbing style. Climber A climbs slowly and statically, Climber B moves quickly between holds. Both expend the same forearm energy overall, they both generally redpoint the same grade. Climber A prefers long stamina type routes, climber B prefers steep short powerful routes......which is the best climber.?
David Coley - on 07 Jan 2018
Hi
For those interested I spent an couple of hours this morning building the rig. Photo here:

https://flic.kr/p/JjPKft

As always, comments welcome
Lurking Dave - on 08 Jan 2018
In reply to David Coley:

Fun topic but as other have pointed out - climbing is much more about the flow and transition of movement between holds rather than static positions.

Strain gauges on the holds at the Olympics would make for an interesting data set... force and power output + the comparisons between shouldering and speed climbing. I can almost hear the American commentator...

Cheers
LD
JLS on 08 Jan 2018
In reply to David Coley:

>"As always, comments welcome"

Build on literally a shoe-string budget.

Are you convinced all the frictional losses, particularly at steeper angles, will cancel out?
David Coley - on 09 Jan 2018
In reply to JLS:

> >"As always, comments welcome"

> Build on literally a shoe-string budget.

> Are you convinced all the frictional losses, particularly at steeper angles, will cancel out?

No. But I'm hoping they will be similar for 8a climbers and for 6a climbers, which is all that is required as this is comparative study only.
TonyB - on 09 Jan 2018
In reply to David Coley:
I know that you're looking at something different, but have you seen the instrument designed with Magnus Midtbø for measuring force applied to a training board? It might be interesting to look whether some of the tech is transferable.

https://www.youtube.com/watch?v=f1BSaEhIgdg
Post edited at 09:48
duchessofmalfi - on 09 Jan 2018
In reply to David Coley:

I think your problem is that you've massively understated the problem:

To make a meaningful study you'd need to vector force and torque sensorise each hold in a reasonable long sequence - say 10-20 holds (~ 3-6 moves) and you'd need a sampling rate in excess of human reactions, say 1kHz and connect the lot up in parallel, so 6*20 sensors ~300 channels at 1kHz, and then you'd need synchronised body sensors and motion capture to capture the body position and momentum -- all possible but significantly more expensive and complex than you're thinking of! on top of all this you'd need to model the friction and bio-mechanical aspects to make sense of it all.

A simple set of scales experiment is so crude that you'll discover that a big jug for the hand and tiny slippery nuggin for the feet favours the hands and vice-versa. Torque, side, shear forces, friction, momentum, body position and CoM play a huge role in climbing - not just the force against gravity.

Obviously you know all this but the instrumentation is the key barrier to measuring the subtly and complexity of climbing moves.

David Coley - on 10 Jan 2018
In reply to duchessofmalfi:

Hi, thanks for that. What I'm hoping is that, by keeping the question narrow and focused, this can all be avoided. I will need a variety of holds and positions and wall angles though.
David Coley - on 10 Jan 2018
In reply to TonyB:

Now that looks ideal. If I could rig that to the hand holds and not measure the feet that would be great.
cb294 - on 10 Jan 2018
In reply to David Coley:
Just was thinking about the same lines as the duchess.

I think you need multiple holds and foot rests, maybe 6 to 8 each, that must be able to measure donward and outward load.

While continuous measurements are ideal, something that records the maximum load on each grip in both directions for a single move may already be informative (the parameters like torque and friction will contribute in a defined way to these two force components which can thus, in first approximation, be used a proxies for the more complicated actual process).

The reason why I suggest to measure two values per hold is that I suspect that one difference in climbing skill may actually lie in optimizing the load distribution especially on the footholds.

Mount these measuring holds on a tiltable back board, and let five climbers per grade bracket climb the thing five times at, say, three angles. Normalize for body weight, and see if you can see anything with such a crude setup.

Classic pilot experiment approach: If nothing pops up first go the hoped for effect will be marginal at best, and you will at least know that finding anything significant is going to be tedious and expensive....

You could also save money by measuring hand and feet separately, by putting the force gauges onto some kind of adaptor plate between wall and hold, and then supplement the board with standard holds either on top or near the bottom.

CB

edit: If present, any effect should be actually visible in one experiment (hand or feet)!
Post edited at 18:50
David Coley - on 11 Jan 2018

Hi,

A graph of the first 8 (look closely as some are nearly on top of each other) data points is here:

https://www.flickr.com/photos/142164361@N06/39631900931/in/dateposted-public/

Although not enough data to draw a conclusion, I think the results indicate that this is worth continuing. 

 

1
JLS on 11 Jan 2018
In reply to David Coley:

Yes, looks encouraging for your hypothesis.

David Coley - on 11 Jan 2018
In reply to David Coley:

The wall was about 15deg overhanging

cb294 - on 11 Jan 2018
In reply to David Coley:

Looks good, and probably has enough data points for a medical thesis.....

CB

John Stainforth - on 11 Jan 2018
In reply to David Coley:

Nowhere near enough points to draw any conclusion. One practically always gets quite a good correlation (from a random spread) with only about half a dozen points.

 

David Coley - on 12 Jan 2018
In reply to John Stainforth:

Hi, 

1. there are 8 points

2. I have not done the stats, but I would guess that with 8 points one might expect a negative slope say 1/3 or the time, a positive slope 1/3 and a mess 1/3. So we are some way from random already.

3. If you look at the data closely, you will see the force increases with grade in ALL cases - this type of relationship is very far from random and quite hard to get with random data (10% of the time with 8 points?). So I think we should not go claiming anything, but I do think it reasonable to suggest it is worth continuing the measurements.

 

John Stainforth - on 12 Jan 2018
In reply to David Coley:

Don't get me wrong. I am encouraging you to get more points. There may well be a valid trend.

TonyB - on 12 Jan 2018
In reply to David Coley:

I know that it's really difficult, but if this were to become a bigger study, it would seem valuable to have some kind of measure of core strength. I suspect that having a strong core (whatever that actually means) helps force the weight onto the feet, and it would be valuable to test whether this correlates better with proportion of force applied to feet then grade. I hear a lot about core, but it's not clear (at least to me) which aspects translate best to climbing and how important it is to have a stronger core versus using better technique to apply the existing core strength maximally.

David Coley - on 12 Jan 2018
In reply to John Stainforth:

Thanks! I'll keep you posted.

 

David Coley - on 12 Jan 2018
In reply to TonyB:

I think you have hit the nail on the head. if the relationship holds true, we need to know if this is because of core strength, or skill.

If core, then train core

If skill, the training core will not solve the problem, but there might be an educational short cut. Possibly using feedback from the rig to help someone.

As we are unlikely to find 8a climbers with a weak core, there is a bit of an issue. However we might be able to work with those working in the 6a/b range. Any idea how to measure core strength is a climbing relevant way?

 

TonyB - on 12 Jan 2018
In reply to David Coley:

I think the problem is that we probably don't know what core strength is actually required for climbing.  I suspect you might need to develop a set up to measure this. One quick answer may be using something like a pull up bar and two footholds at a set distance away. Weight could be added to a harness until the person is unable to keep their feet on the footholds.

Also, I'm not sure why you want to work with people in such a narrow grade range. I would have thought that to test your theory, you would want as large a grade range as possible. 

 

 

 

JLS on 12 Jan 2018
In reply to David Coley:

 

>Any idea how to measure core strength is a climbing relevant way?

I was about to say time a "plank" to failure then it occurred, for what you are doing, a "reverse plank" might be more appropriate...

 

TonyB - on 12 Jan 2018


> I was about to say time a "plank" to failure then it occurred, for what you are doing, a "reverse plank" might be more appropriate...

I wonder if doing anything to failure is testing endurance rather than strength. 

 

David Coley - on 12 Jan 2018
In reply to TonyB:

 

> Also, I'm not sure why you want to work with people in such a narrow grade range. I would have thought that to test your theory, you would want as large a grade range as possible. 

Hi. 

For the main question I'm working with the full range of 6a to 8a.

For  the question of core strength the problem is that there might not be any 7b to 8a climbers with a weak core. So using 6a to 6b or so might show a realitively greater range 

 


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