The transmission of forces
Ah, connections and learning, it's so satisfying!
The internet is a wonderful thing. Well, it can be, at times, anyway. How many times have I wanted to ditch Facebook out of boredom and yet there are some people sharing really valuable hard-won information. One of my current favourite pages is 4DimensionDressage, ran by vet Dr. Liedbrandt. They had a really interesting post the other week about the different fitness requirements of endurance horses versus dressage horses, which was great because when you begin learning about equine anatomy and how it relates to riding there is so much concern about "roundness" through the back as being the only way to ride a horse without damaging it that you wonder how racers, eventers, and endurance animals do it. I still don't really know the answer, but I think it's to do with "strong neutral" through the spine.
Anyway, today's post was about problems in the neck. He was writing specifically about arthritis but the reason I found the post so interesting was that it confirmed and pulled together bits and pieces that I've picked up elsewhere. How easy it is for the neck to shorten/concertina, in large part due to the fact that the lamellar portion of the nuchal ligament doesn't extend to C6 and C7 (as discovered by Sharon May-Davis over her many educational dissections over the years) and so the base of the neck drops. How that takes the withers with it, dropping the horse more onto the forehand, and contributing to atrophy behind the scapula/wither. How this often goes hand-in-hand with a bulge at the loins (though I still don't quite understand the connection here yet). And, from his point of view as a vet, how so many horses have neck problems, mostly as a result of contact that is too tight/short.
He even spoke about how today's sport horses may be genetically predisposed to problems like arthritis as their slim hypermobility has a price: "they cannot stabilise their body properly." And I'd been thinking/writing about that a few months ago, as a friend's hypermobility got me thinking about the relationship between flexibility and stability. We generally all think we need more of the former, and this belief seems to apply to the way people train horses too, but surely, for any average creature, what you need is an equal balance of the two.
Very much looking forward to SMD's dissection in April. I've been watching whatever educational dissections I can find on youtube recently, sometimes whilst on the treadmill actually, makes the time pass better! Stumbled across the racehorse edition of Inside Nature's Giants, which I remember watching on channel 4 years ago. Horses are so economical with their movement. I suppose it's what allows us to harness their athleticism. The breathing at canter and gallop is fascinating. Up to 4 breaths per second. Once their lungs are fully expanded they don't so much actively breathe in and out, instead the ribcage stays expanded and the diaphragm is violently thrust back and forth by the movement of the viscera inside the abdomen, which pushes/pulls air in and out automatically. Hence when you canter along and hear that lovely rhythmic breathing. Horse has no choice but to breathe rhythmically when in canter or gallop. I wonder if they find calmness in rhythmic breathing, like we do. We certainly believe they find calmness in rhythmic movement, hence lots of trot, but perhaps a steady canter is another route into relaxation. Watching the section where they put a forelimb under huge vertical pressure also showed perhaps why their cannon bones have that small amount of cranial bend (they're not perfectly straight)... it seems to be because the tautening of the tendons down the back of the leg would bend the bone backwards otherwise. So whilst the bow-and-string theory of a horse's back is something still apparently under question, the cannon and tendons do seem to follow that sort of model. They both bow outwards slightly under pressure, then once the pressure is released the stored elastic energy pings them back to "straight", sending the limb up off the floor. The comparatively tiny biceps don't need to do much to pull the leg forward as a result. As I think they said in the show, it's like a pogo stick. One of them said that we don't have any materials in the man-made world of engineering to even come close to matching the capabilities of these tendons. Isn't that amazing.
I have had a couple of tiny runs the past few days, whilst out walking. Which would be nothing to anyone else, but to me that represents quite a big step forwards. I would always struggle to jog as my posture would brace to protect my lower back, which has been weak ever since I took my first sit-down job ten years ago. Top tip: never take a sit-down job kids. The advice was always to stretch it out, but no, apparently that isn't recommended now! The proprioceptive relief you get from stretching an already too-stretched area is actually harmful longterm. So about a month ago I stopped myself from giving in to the wish to stretch my lumbar spine and it seems to have started stabilising. I hadn't realised how much my movement, especially beyond a walk, was subtly braced to protect my back. Without that defensive posture there, one can actually run a little bit!
I'd been thinking about how when we talk of horse's flexing the hind limbs what we're getting at is that they become better at absorbing shock. Not that their hocks or fetlocks ping everywhere whilst the rest of the leg resists, but that all the joints compress to absorb the shock and let the forces generated travel up through the spine, be harnessed by the rider, and dissipate safely. Without bracing around my lumbar spine, my joints were able to share the work of shock absorption more evenly. In the past, when I've tried to jog for fitness, it's felt impossible. And I realised these past few days it's because a defensive lumbar spine = a static pelvis, which increases the work expected of the ankles and knees. Running "from the knees" is a miserable thing. Running from the hips is far easier! Footfall is quieter, posture lasts longer, lungs/heart find it easier, the knees don't suffer so much, and it feels forward and springy. Who knew?