Caver Anatomy

[Les W]

Works for me : :

Works for me too  but what about the image link...  :chair:

 

[Roger W]

Ah, yes.        Can you still get that pattern of caving boot?

 

[Roger W]

Going back to Amy's point, though - while these young ladies are undoubtedly attractive, do they actually give a fair representation of normal caving physique?  And how should we measure that physique?

BMI has its drawbacks - a high BMI does not distinguish between "fat" and "muscular" for example - but I take it that it does distinguish between "thin" (i.e. able to squeeze between the back of the bench and the seat) and "chunky" (i.e. gets stuck trying to squeeze...)*  Chunkiness would appear to be a problem in tight passages - but how big a problem is it on SRT?  Obviously, "fat" - that is, simple excess poundage - is going to be that much dead weight to lift whatever height or shape you are.  But how about muscle? 

In my competitive cycling days, the skinny lightweight riders seemed to be better than the chunky muscular guys when it came to hill climbing...

*  OK - I know a very small, but overweight person might be able to squeeze through a gap where a much larger, but technically underweight person could get stuck...  Maybe we need a "maximum circumference measurement" or something for this?  And my question also fails to mention fitness and things like that.  But, in general,  can a skinny, lightly-built caver out-prussik a more muscular but heavier one?  Or is sheer muscle-power what is important?

Modified by me as a result of an afterthought...

 

[droid]

Surely it's about power to weight ratios?

It's a different deal with cycling and the skinny climber versus thickset sprinter.

 

[potholer]

Surely it's about power to weight ratios?

It's a different deal with cycling and the skinny climber versus thickset sprinter.

Presumably, for more than brief sprints, it could come down more to heart/lung-output-to-weight ratio than power to weight?

Skinny and/or leg-heavy climbers might have advantages in terms of naturally being closer to the rope without needing to pull with arms.

Fit-but-muscular cavers with decent upper body development might be carrying a fair bit of heavy muscle of which much is of little or no use in getting up ropes.
Someone skinny who caves regularly may put on muscle where actually needed while staying skinny elsewhere, and end up closer to an ideal climbing build.

 

[TheBitterEnd]

There's a theory about fast twitch and slow-twitch muscle fibres- compare Usain Bolt and Mo Farah. For short fast bursts of energy you need lots of fast twitch fibre, for endurance lots of slow twitch.

So the muscular cavers are likely to be able to do a fast short burst but will be overtaken by the skinny guys over distance.

 

[jonnyrocketboots]

Guys, years back I did a few courses in personal training and stuff like that and I should think I've forgotten more than I know now but... Caving/Climbing is an aerobic sport requiring a lean body type depending on red and some pink muscle fibres. Aerobic exercise relies on blood carrying oxygen and fuel to the muscles.  So the less fat we have the less weight the muscles have to push! Big powerful types tend to tyre quickly at these sorts of exercise as they are better at Anaerobic exercise as they have more white muscle fibres which use a different fuel within the body.  White muscle fibres are powerful but burn out quickly.

I'm sure someone can explain it better than me and I would be glad for a reminder, like most things Ive probably got it round my neck!!

Scott

 

[Roger W]

Big powerful types like bodybuilders and weightlifters might be developed for anaerobic exercise, but surely cycling is an aerobic business?  Ditto prussiking, I would think - at least up long pitches.  And in the days when I was thin and skinny with muscular legs I could still beat Mike C up hills, but he - shorter than me but stocky and heavily built - could leave me standing on the flat - and not just over short distances.  Cycling, I know, and not caving - but what I was wondering was, does the same apply to prussiking?

 

[bograt]

From my perspective the ratio of limb length to torso length is a factor, a short limbed dwarf like me will have to work twice as hard as the moderately proportioned Moose to cover the same distance on a rope.

 

[droid]

That's a god excuse.

I'm going to steal that

 

[bograt]

I don't do excuses, just reasons. 

 

[And]

Limb length is overlooked. There was a good article in Descent a few issues ago about body shape to SRT efficiency. The key thing, at least from my perspective, it missed out, was arm length. I think I must have quite short arms (or body!), so I can't get the jammer on the footloops that far from my croll, so even though I could take biggersteps, my stroke length is limited by how high I can push the jammer up.
  Indeed this is the argument against having a high point of attachment for a croll on a harness, as it reduces the stroke length as it moves the croll closer to the jammer.

 

[droid]

Not a lot of point getting a good jammer height if your leg length isn't long enough to take advantage of it.

Bograt has a good point. If you're short limbed you have to do twice the movements.

And it's both a reason and an excuse. It excuses slower prussiking

 

[And]

Indeed, it's not much good getting the jammer higher for some, but as I said it's my limiting factor. I must have long legs and good movement in my joints.  Unlike Amy, raising my croll would hinder me.

I fall back away from the rope too, and I'm not fat (are there fat cavers?). I use a torse, like Simon who posted earlier, and Amy uses that weird bungee thing, and these could be the source of the problem. I think because the bra-style chest harnesses  pull in the croll laterally to the chest as well,  it is held much tighter to the chest than with a torse-type strap. The torse just seems to hunch me over, pulls my shoulders down and curves my back, moving the jammer away from my chest.

Part of my problem too is probably due to my crap Singing Rock harness that is impossible to adjust!

 

[wookey]

Raising the height of the Croll potentially decreases the length of the step and thus manoeuvrability would also  be affected.

No it doesn't, as Amy explained in the vid, (unless your step-length is already limited by the length of your arms even with a low chest jammer). It means you need a longer footloop for the same step length, and you have to lift your hand-jammer higher. So there is a tradeoff of either a higher hand-jammer lift height _or_ a shorter step size ('bite'), for a higher chest jammer. I can see that this may well be an improvement for the top-heavy (OK, lardy) caver. I don't know how many top-heavy types also have their bite limited by arm-length. For them you are right, but mostly step-length doesn't really matter - only when the rigging is awkward and a bigger step can save you some aggravation.

 

[cap n chris]

There was a good article in Descent a few issues ago about body shape to SRT efficiency.

It was a good idea but ended up being a rubbish article, with no conclusions and incomplete research.