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We Are Flying Solo

December 18, 2010

Oxygen Optional

We were talking about nutrition. And you've been up for days waiting for the secret to growing that unicorn horn (don't lie, own it).

Too bad.

Here's another, possibly equally as important tidbit, though. Different athletic disciplines make different demands on a horse's body. I know, thank you Captain Obvious, right?

But here's the breakdown: there are two basic types of metabolism. (1) aerobic (the muscles use oxygen while generating energy; a slow process) and (2) anaerobic (yes, you guessed it, genius; the muscles generate energy without oxygen; much speedier).

A horse who is working in a long, steady fashion (think endurance racing or your dressage school) gets to create energy aerobically. He has an advantage because this is a much easier and longer-lasting method of working. You see, fat is a horse's go-to fuel and in order to burn it, his body must use oxygen (just like your fireplace must have a flow of oxygen to burn up your firewood and create heat).

However, if Dobbin has to work hard and fast (think sprinting or jumping), he cannot get oxygen into his body and burn fat fast enough to create the energy he needs. So his muscles turn to his glycogen stores, which can be burned anaerobically. In short, glycogen is a carbohydrate stored in the liver and in muscles that the body can convert to glucose (muscle fuel).

Glycogen is a finite resource, though, and stores are smaller than his fat supply. Burning it also produces lactic acid, which fatigues muscles. So, you, as pilot, want to save that glycogen until you really really need it. You want to save that hard sprint or gallop, which burns up those precious reserves, for your horse trial or other vital moment. And once he burns it up, you have to make sure to give him time to replenish the storehouse before you ask for it again. The more glycogen he has stored up, the longer he can go in a demanding situation before he fatigues.

If he gets really desperate, Dobbin can also turn to blood glucose for energy. His nervous system needs this to function, though, and there isn't much of it (about 1% of the body's fuel supply), so we don't really want to push him this far.

Is your brain fried by science-geekness yet? I could go into ATP and muscle cell pH, so be grateful...

Why the heck should we care about all this anyway? In my opinion, knowledge is ALWAYS power when it comes to horse management. If I understand what my horse's body needs to do his job and how it uses what I give him, I am better able to meet his needs and maximize his performance safely.

Because you need to understand all of that to understand this, the point we act on: the more fit your horse is, the better he is able to utilize his fat stores first. The unfit horse may have to get up to 40% of his energy from his glycogen reserves during even light exercise. When you fit him up, he can drop that percentage dramatically even during moderate exercise, meaning his body won't quit on him for much longer.

So should we stuff our horses full of lard? How do we refill his glycogen tanks? All this and more, tonight at 11. Ok, not actually at 11, but you clever ones out there got it...


  1. Sounds like my college-level Bio class!! I love reading stuff like this, and it's all so true! There are REASONS you do a lot of slow and steady work and very few sprinting, so pony can get fitter and build up body reserves, so you can do that occasional sprint when you need to and pony won't shut down then or later. Can't wait to read the rest!

  2. Oooo, ooo, are we gonna get into the sliding filament theory and sarcoplasmic reticulum and how calcium is essential for muscle movement? Yes, I am a closet science geek! (And I might have also once been a certified personal trainer looong, looooooong ago, not that you can tell that by my heifer-ness!)

    So, do we carry those goopy energy gel thing-ies that marathan runners use, and feed them to Ponykins? Cuz that would be fun!

  3. Snap I never really thought of all that before!

  4. Hahah, dressager, yes, I was having school flashbacks too!

    No, Frizz, I am not releasing the hounds. If anyone wants to know google is their friend (and I'm not typing all that crap, LOL!). If you can get Dobbin to eat his gel pack, well, it's just salt and glucose! I'll let you in on a little secret -- lifeshighway's horse thinks that CliffBars are crack.

    Checkmark, I'm here to do the thinking for you! ;-)

  5. yup yup, sounds just about right. Also, acetate, which is produced by microbes in the hindgut, is the volatile fatty acid that horses use the most, and slowly fermentable carbs (like cellulose and hemicellulose) are the best ways to get more acetate. I just took an equine nutrition class :D Could you tell that I got an A?

  6. It sounds like you passed the exam with flying colours, tangerine!! ;-)

  7. ATP! ATP!

    Biology! Yay!

    You should do more posts like this. It soothes the inner science freak. (Well, I guess outer too, since I'm a Bio major, but still.)

  8. Awwwww, I love it when my fellow geeks come out to play!!

  9. ooooooooo! Go into ATP and muscle ph please oh please!!!!

  10. Ahahah, sorry, Alana, that would feel too much like work!

  11. Life is full of disappointments, my friend. I am only one of them.