Realities Created, Maintained and Destroyed, WHILE-U-WAIT!

Thursday, October 01, 2009

The great running discussion

If you have been following the comments on my running posts you know that there is a lively conversation going on between myself and my friend Steve Perry .

Since the conversation is on a topic that I have great interest in, and since Steve is an excellent debater, who will force you to be on your best game to keep up with him I have decided to move the whole discussion to the main blog and to invite Steve in as a guest blogger on this topic. He has kindly agreed, So I will be posting Steve's thoughts as full articles here.

So I will start with Steve's last comment and take the discussion from here. His comments are in green.

Indeed, the philosophical and mechanical hair is being split here.

To continue doing it:

In the warm days, we work out in the sand pile in my teacher's front yard and most of us, certainly i, do so sans shoes. Our feet do pretty well on such a surface.

On the chilly and rainy days, we work out in Cotten's garage, and since our feet were originally built in the tropics, don't do well on concrete when it is cold, I wear shoes. And sometimes a hat and gloves.

Can't says that I blame you for that, it's a matter of personal comfort rather than genetic adaptation though. While our feet as they are today were evolved in the Savannas of East Africa, and that part of the world has a pretty nice climate for humans, (I have never lived so comfortably climate-wise anywhere else in the world as in northern Tanzania) it does get cold there. Not as cold as in northern Oregon, but cold enough.

There is hard pan out on the veldt, but we weren't evolved to run on it, (or anything else. Running down deer is a long an slow haul, and inefficient at best. Running from the big cats is a way to die tired.)

Our physical make-up is a hodge-podge. No claws, dull teeth, no fur, we are slow, we take to long to mature, and if it weren't for the big brain and opposable thumbs, we'd be everybody's prey.

While what you say was the common wisdom some years ago, it is a position that is no longer quite so defensible.

I would suggest to you that running was exactly what we evolved to do on the savannas of East Africa.

The evidence for this is right there in our physiology. We have certain characteristics found only in running animals, and a couple that make us good runners that are unique to us.

Let me ask you to speculate on a couple of things. About two million years ago with the emergence of Homo Erectus, we began to develop much larger brains. This was undoubtedly because we managed to find a good, reliable source of protein in quantities not available to our relatives. We know this because of both skull capacity and dentation.

There are a couple other interesting changes from Australopithecus (or perhaps Ardipithecus ramidus, the information on this new species has not been out long enough for me to draw any conclusions other than it was a walker rather than a runner judging from the feet)

One thing that shows us that that we took up running is that we, as well as Homo Erectus have a nuchal ligament. This is a ligament that runs from the base of the skull to C7 and is only found in running animals, its job is to stabilize the head at high speed. Chimps (our closest living relatives) do not have one, Australopithecus didn't have one, Homo Erectus did, we do.

We also have a well developed Achilles tendon. This is a development that has no real use in walking, and as a matter of fact tends to get in the way. Again Chimps do not have an Achilles tendon to speak of, but Chimps are walkers not runners and are well adapted to this. For a discussion of this at length see the paper "Endurance running and the evolution of Homo" (Bramble and Lieberman, 2004, link is to a pdf of the paper)

Then there is the fact that we have an arch in our foot with a well developed plantar fascia with short toes facing forward, these are traits useful for running rather than walking while the Chimp has flat, splayed toed feet adapted well for walking.

As a mater of fact, as you can see from the chart below, the very muscles most involved in running are well developed in us but not in our walking relative, the Chimp.


As to not having fur, that fact along with our copious sweat glands give us the most effective cooling system in the animal kingdom. The primary cooling mechanism for most mammals is panting, where they exchange heat through the breath. We on the other hand shed heat through our skins by evaporation, also a useful trait for running. That is of course if we are talking about endurance running rather than sprinting.

Then we have to take a look at our breathing mechanism in contrast to other mammals. All quadrupeds are limited to one breath per stride cycle at a gallop. They can't pant and gallop at the same time, so they can't shed waste heat that builds up at top speed. We on the other hand, can regulate the frequency of breath at any speed and we are pretty unique in this. It is likely that this particular adaptation came with our upright stance.

You suggest that "persistence hunting" (chasing down prey) is inefficient, but I have to ask on what data you base this assumption?

Lets take a look at some hard data. A deer trots at about 3 to 4 meters a second and a man jogs at about the same speed, when a deer accelerates past 4 meters a second he has to break into a gallop which limits him to one breath per stride cycle. So at 4.1 meters a second the deer is building oxygen debt and waste heat while while a man has not yet gotten out of a comfortable aerobic range. The deer can hold a gallop for about 10 minutes then it has to slow to a trot again. A good human runner can jog at 6 meters a second all day long. So the math roughly works out to this, on a warm day a human (you actually need a group of humans, but more on that in a sec) can run a deer to exhaustion and heat stroke in about 15 to 20 km.

I had the privilege to witness a persistence hunt on the Navajo Rez back in '69. In order to make their sacred masks for healing ceremonies, they must have "unbroken deer skin", that is from a deer that has not been killed by shooting or stabbing. Their method of obtaining this kind of hide is to run the deer down, then finish it by smothering it with corn pollen. It took about two hours for 6 men to do this. You need to work in a group in order to keep the deer running and not allow it to get to a place of safety to rest.

Here is a pretty nifty video of some San people persistence hunting.
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Our ancestors started getting a consistent high quality protein diet about two million years ago (about the same time we began showing the traits of a running animal) but we did not start making stone spear points until about two hundred thousand years ago. We might have used bone points a bit earlier, but it is hard to tell as bone tools tend to degrade. So how did we catch our dinner when the best tool we had was a club or sharpened stick? Sharpened sticks make lousy missile weapons, especially when propelled by wimpy human arms. Persistence hunting is quite viable under these circumstances.

Then we have the problem of the Neanderthal. He was at least as smart as us, perhaps smarter, he made tools as well as us, was a lot stronger and could work cooperatively with his fellows in very complex ways. It would seem that he and not us should have won the day and now be populating the planet. But we showed up just as the climate was warming and the larger animals that were the favored prey of the Neanderthal were vanishing. He, from what we can tell from the fossil record, was not a very good runner and his massiveness would mean that he would overheat much more quickly than skinny us (Neanderthal was about 5'5" and 180 lb from what we can tell where as humans were a bit taller, but also lighter. Weight difference is fairly significant in running).

The fact of the matter is that humans are the best endurance runners the planet has ever seen, and we are quite unique in this respect.

We did not develop this trait for no reason. Species do not evolve to become weaker and less capable. If we gave up speed and strength we had to get something that was better in return, or we would not have survived.

There has been, until recently, a prejudice towards sprinting animals as being best adapted as runners.

We are not as you suggest a "hodge-podge", we are superbly adapted endurance animals and running all day is what we do better than anything else on the planet. It has only been since the crippling effect of modern over padded, over engineered running shoes that we have found ways to hurt ourselves doing so.
Running barefoot in the snow is a gimmick, and iffy. If your feet are numb from the cold -- and they will be -- then you can't feel the imperfections in the road any better than you can in thick-soled running shoes.
Of course it was a gimmick, he was raising money for charity, and the news cast did mention that he had given himself at least one case of frostbite while out raising that money. But I run around barefoot in the snow every winter without my feet going numb. Like you, I learned a bit of Tumo in my youth and it allows me to keep my feet warm in those circumstances. I have not tested the limits of my skill, I don't practice as much as I should but I can do 20/30 minutes without my feet getting cold or numb. (there are a couple of people who post here that have seen me do this if you need corroboration) But it still is just a gimmick. It does point out though that what we choose to tolerate is not the same as what we can tolerate without injury.
The degree of training necessary to get your soles in shape to run on concrete involves building sufficient callus to deal with repeated landings and take-offs on a surface that eats soft tissue. You can do it, but it's rather like pounding a steel plate to toughen your knuckles ...
This has not been my experience. Each spring it takes me about three weeks to re-adapt to running around outside barefoot. It takes me less time to adapt to smooth surfaces such as concrete than it does to rougher natural surfaces. Interestingly, my feet are not particularly callused even though I am barefoot for most of every day and wear very thin shoes as a rule through most of the year. I think I get more calluses wearing boots in the winter. The thing is, callus does not protect from repeated take off and landing, that is the job of your ligaments and tendons. Abrasion happens more with poor running/walking form than from impact.

For me the bottom line it this. We are running animals, but we are not sprinters like the cheetah or the deer, we are endurance runners. That's what we evolved to do. We run best when our footwear allows us to use our feet as they were designed to be used, and that there are significant health benefits to running this way. There are also significant benefits to running and walking barefoot. Those being; it will help perfect your running and walking form, it will strengthen your feet and ankles, it will improve your balance, and it seems to have a positive overall effect on your nervous system.

I should mention, in the spirit of full disclosure, that I have been of the school that supports the idea of humans as endurance based animals since I was an Anthropology student back in the early '70s. Back then we were not taken very seriously, but time has born us out and shown the "crippled but smart ape" school to have been quite wrong.

1 comment:

Barefoot Ted said...

Howdy Mushtaq

This is amazing stuff you share on your blog. I love it!!!

Keep up the great work.

Barefoot Ted