As I plodding along on my treadmill in a state of anoxia-induced receptiveness last night, the fitness trainer was saying that people are often “sided” in part because we’re not anatomically symmetrical. The heart is on one side which makes the lungs different sizes, the kidney is on the other side, etc. This trainer was saying that most people carry their left shoulder higher and slightly forward, just because of heart location and its impact on the lungs. I don’t buy into everything this trainer says, but it made me wonder if horses are anatomically symmetrical. Where is their heart? What other organs might be asymmetrical such that this could in theory affect their “sidedness” under saddle?
This seems far more likely to be caused by the human tendency to carry heavy things in their dominant hand or over their dominant shoulder (think kids with their heavy knapsack carted about with only one shoulder strap in use).
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I would tend to take anything a trainer who thinks the “heart is on the left” with a grain of salt.
Yes, because of its shape and orientation, a bit more squishes left of center. Your heart is centered directly under your sternum, though.
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The heart isn’t “on one side”. It’s slightly left of center. But yes, that slight left of center does mean the left lung is a bit smaller than the right. That said, the right lung is shorter because the liver is in the way
Horses aren’t anatomically symmetrical, I’m not sure any mammal is, since there are multiple single organs, our intestinal tracts aren’t perfectly balanced left to right, etc.
Horses’ hearts are also more towards the left side. I don’t know that organs inherently make us asymmetrical though. We’re much more likely to be asymmetrical due to not having both legs exactly the same length, or hips exactly level, and more.
Every being has a preferred side of usage - dominance, whatever you want to call it. More humans are right-handed than left, which impacts strength, but also how you tend to position your upper body relative to your lower body (that torso twist, one shoulder a bit more forward and/or higher/lower), so that impacts shoulder position MUCH more than the heart being slightly to the left of center.
I’m not sure I’d buy into a lot of what that trainer says, if they think the heart is on the left and that, combined with a smaller left lung, is what makes “most people” carry their left shoulder high and forward.
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Am I the weird one who carries heavy things in my non-dominant (right) hand so that my dominant hand is free for things that require some dexterity? I always carried my backpack on my right shoulder, always put my purse over my right shoulder, always carry bags in my right hand (unless I need both hands), so that my left is free to open doors, insert keys, etc
I mean, if it’s a straight carry, and it’s heavy, I alternate - gas cans for example.
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I read a while ago a book called “A Left-Hand Turn Around the World”. Loved it -
Few things from the book - people are “sided”, not “handed”. How sided you are is dependent. There is a list in the book where you can think about what you do with each hand/side. Do you more often kick a ball with left or right foot? Brush your teeth with left or right hand or both? Use a fork? Carry thing? Etc.
The author did a lot of research on sidedness throughout history and compared to animals as well. Throughout history the human population has favored right-handedness (and hence people who are more right sided) than left. This is through war - he noted that because the heart is slightly to the left, it is more likely that an arrow will find it’s mark around a shield. Through politics - left handed people are evil and more likely killed. Through mechanics - as mechanization increased, equipment was generally made for right handed people and left handed people were more likely to get injured/killed (like scissors but more).
This is the reason I do not want to use a chain saw. I know I can learn to do things with the left side but when an emergency happens, your brain wants to use it’s dominate hand more than its recessive hand and I am VERY left sided so I don’t doubt my brain will want to fix the problem a certain way and there goes my arm. My dad used to say my mom was clumsy because she was “coerced” into switching from left-handed to right-handed and was ambidextrous as a result. So her brain didn’t know which hand to use in “emergency” (like a glass falling off the table you want to catch).
(SIDE NOTE on war - there was a very historically famous slingshot battalion of all left handers - I think it was during the Roman Empire. There is also a castle in, I believe Scotland, that was owned by a left-handed royalty and the spiral staircases went the other way, which put right-hand attackers at a sever disadvantage. So war isn’t all bad for lefties)
These same issues did not occur in animals and the author found that animals tend to be more 50/50 on sidedness.
I remember telling someone this and that person mentioning that this is incorrect because some big name (I think Reiner Klimke - someone big and old school) said all the horses he rides are right sided. But here’s the thing - if you as a person are very one sided, wouldn’t your aids be better at getting a horse to move well going one way than the other? Personally, I have found horses about 50/50.
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That was the other thing I was going to mention - people usually carry items in their non-dominate hand in order to manipulate items with their dominate hand, which is better at fine motor skills.
So, the “left shoulder up and forward” is probably due to people carrying their backpack just over one shoulder and when done that way, the arm is not as useful as you need to either hold the strap or hold your arm a certain way in order to keep it there (personal physiology depending). Not to say it is totally useless, just compare opening a door with the bag over the same shoulder as the hand you are using, compared to the opposite.
That’s why saluting with the right/carrying with the left in the military isn’t hard for most people but people like me have to have little tricks (like I would carry my car keys in my right pocket so when walking out of the building, I switch everything from right hand to left hand to get keys out instead of being blindsided and shuffling when potentially seeing an officer.
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do you know if horses were studied in that conclusion of more or less 50/50 on sidedness? I seem to recall something on horses about positioning in the womb, as at some point they’re just too big to do anything but be curled one way, which results in a preference at birth for some sidedness, however subtle. Combine that with the fact that a lot of horses don’t have symmetrical front feet, which makes a preference for 1 foot forward/1 back, and you get more of a sidedness preference.
I DO know that my trainer used to tell me that the best fix for a “right handed” horse, was to get a leftie to ride them LOL Absolutely how people handle a horse impacts them. Leading only from the left, always mounting from the left, their own asymmetries, and strength/suppleness imbalances while riding, all create the same asymmetric, unbalanced horse.
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I’m looking it up now…but the author notes that parrots are also a 9:1 ratio (like humans) but favor the left side. A particular chimp group he visited was 70% seemingly right-sided but other researchers disagree with this particular researcher’s claim that this is true across the entire chimp population and is only true in this particular group.
I thought there was something about dogs and horses and other domestic animals but I’m not seeing it right now. I may have just been making mental connections while reading.
Obviously this means I need to read the entire book again…but so many other books I’m in the middle of right now…sigh
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Actually I think this is normal. I am right handed so I carry my purse on my left shoulder, carried the toddlers on my left hip, ( so I could stir, pay the cashier, whatever) with my right hand.
