One Foot In Front Of The Other

According to many, the thing that really sets human beings apart from the rest of the natural world is our mastery of locomotion; the ability to move faster, further and with heavier loads than any other creature typically does (never mind that our historical method of doing this was strapping several other animals to a large heap of wood and nails) across every medium our planet has to throw at us; land, sky, sea, snow, whatever. Nowadays, this concept has become associated with our endeavours in powered transport (cars, aeroplanes and such), but the story of human locomotion begins with a far more humble method of getting about that I shall dedicate today’s post to; walking.

It is thought that the first walkers were creatures that roughly approximate to our modern-day crustaceans; the early arthropods. In the early days of multicellular life on earth, these creatures ruled the seas (where all life had thus far been based) and fossils of the time show a wide variety of weird and wonderful creatures. The trilobites that one can nowadays buy as tourist souvenirs in Morocco are but one example; the top predators of the time were massive things, measuring several metres in length with giant teeth and layers of armour plate. All had bony exoskeletons, like the modern insects that are their descendants, bar a few small fish-like creatures a few millimetres in length who had developed the first backbones; in time, the descendants of these creatures would come to dominate life on earth. Since it was faster and allowed a greater range of motion, most early arthropods swam to get about; but others, like the metre-long Brontoscorpio (basically a giant underwater scorpion) preferred the slightly slower, but more efficient, idea of walking about on the seabed. Here, food was relatively plentiful in the form of small ‘grazers’ and attempting to push oneself through the water was wasteful of energy compared to trundling along the bottom. However, a new advantage also presented itself before too long; these creatures were able to cross land over short distances to reach prey- by coincidence, their primitive ‘lungs’ (that collected dissolved oxygen from water in much the same fashion as modern fish gills, but with a less fragile structure) worked just as well at harvesting oxygen from air as water, enabling them to survive on land. As plant life began to venture out onto land to better gain access to the air and light needed to survive, so the vertebrates (in the form of early amphibians) and arthropods began to follow the food, until the land was well and truly colonised by walking life forms.

Underwater, walking was significantly easier than on land; water is a far more dense fluid than air (hence why we can swim in the former but not the latter), and the increased buoyancy this offered meant that early walkers’ legs did not have to support so much of their body’s weight as they would do on land. This made it easier for them to develop the basic walking mechanic; one foot (or whatever you call the end of a scorpion’s leg) is pressed against the ground, before being held stiff and solid as the rest of the body is rotated around it’s joint, moving the creature as a whole forward slightly as it pivots. In almost all invertebrates, and early vertebrates, the creature’s legs are positioned at the side of the body, meaning that as the creature walks they tend to swing from side to side. Invertebrates typically partially counter this problem by having a lot of legs and stepping them in such an order to help them travel in a constant direction, and by having multi-jointed legs that can flex and translate the lateral components of motion into more forward-directed movement, preventing them from swinging from side to side. However, this doesn’t work so well at high speed when the sole priority is speed of movement of one’s feet, which is why most reconstructions of the movement of vertebrates circa 300 million years ago (with just four single-jointed legs stuck out to the side of the body) tends to show their body swinging dramatically from side to side, spine twisting this way and that.  This all changed with the coming of the dinosaurs, whose revolutionary evolutionary advantage was a change in construction of the hip that allowed their legs to point underneath the body, rather than sticking out at the side. Now, the pivoting action of the leg produces motion in the vertical, rather than horizontal direction, so no more spine-twisting mayhem. This makes travelling quickly easier and allows the upper body to be kept in a more stable position, good for striking at fleeing prey, as well as being more energy efficient. Such an evolutionary advantage would soon prove so significant that, during the late Triassic period, it allowed dinosaurs to completely take over from the mammal-like reptiles who had previously dominated the world. It would take more than 150 million years, a hell of a lot of evolution and a frickin’ asteroid to finally let these creatures’ descendants, in the form of mammals, finally prevail over the dinosaurs (by which time they had discovered the whole ‘legs pointing down’ trick).

When humankind were first trying to develop walking robots in the mid-twentieth century, the mechanics of the process were poorly understood, and there are a great many funny videos of prototype sets of legs completely failing. These designers had been operating under the idea that the role of the legs when walking was not just to keep a body standing up, but also to propel them forward, each leg pulling on the rest of the body when placed in front. However, after a careful study of new slow-motion footage of bipedal motion, it was realised that this was not the case at all, and we instead have gravity to thank for pushing us forward. When we walk, we actually lean over our frontmost foot, in effect falling over it before sticking our other leg out to catch ourselves, hence why we tend to go face to floor if the other leg gets caught or stuck. Our legs only really serve to keep us off the ground, pushing us upwards so we don’t actually fall over, and our leg muscles’ function here is to simply put each foot in front of the other (OK, so your calves might give you a bit of an extra flick but it’s not the key thing). When we run or climb, our motion changes; our legs bend, before our quadriceps extend them quickly, throwing us forward. Here we lean forward still further, but this is so that the motion of our quads is directed in the forward, rather than upward direction. This form of motion is less energy efficient, but covers more ground. This is the method by which we run, but does not define running itself; running is simply defined as the speed at which every step incorporates a bit of time where both feet are off the ground. Things get a little more complicated when we introduce more legs to the equation; so for four legged animals, such as horses, there are four footspeeds. When walking there are always three feet on the ground at any one time, when trotting there are always two, when cantering at least one, and when galloping a horse spends the majority of its time with both feet off the ground.

There is one downside to walking as a method of locomotion, however. When blogging about it, there isn’t much of a natural way to end a post.

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Who is most impressive?

As one or two of you may have noticed, the Olympics are almost over, prompting the requisite large party and giving some Brazilians a chance to wear odd clothes, dance about and generally play to stereotypes (probably- I’m feeling a little cynical today). However, in not too long a time that other, perhaps more understated, tetrannual sporting party will get underway: the Olympics’ disabled cousin, the Paralympics.

In some ways this will be a spiritual homecoming for the Paralympic Games- founded in 1948 for ex-servicemen with spinal injuries after the Second World War, it was the brainchild of Dr. Ludvig Guttmann of Stoke Mandeville Hospital, Great Britain (the sports centre at Stoke Mandeville is still called the Guttmann centre in his honour, and one of the two mascots for London 2012 is called Mandeville). Guttmann was a Jew, and had emigrated from his native Germany in 1939 to escape persecution from the Nazi government of the time. He founded the National Spinal Injuries Centre at Stoke in 1944, and founded the ‘Stoke Mandeville Games’ (to coincide with the 1948 London Olympics) in response to his feeling that sport could be use as a form of therapy for the seriously disabled, giving them purpose and self-respect. His vision was a great success, ballooning in size and popularity until, in 1960, it became officially tied to the Olympics proper (it wasn’t called the Paralympics until 1984). Guttmann himself was showered in praise for his work, being awarded (among other things) a CBE, OBE, and a knighthood in 1966.

Since then, the Paralympic movement has continued to inspire and amaze. Since 1960 non-war veterans have been eligible to compete, and multiple categories of disability have been entering since 1976. For many, the very existence of the Games has been a beacon of hope for lives torn apart by accident or injury, something to focus their otherwise unspent athletic energies upon, and thus fulfilling Guttmann’s vision of sport as a therapy. For a special few, they have been a springboard to their being able to compete amongst able-bodied counterparts, in sports ranging from sprinting to shooting to swimming.

Paralympians, obviously, do not have the physical capacity to match able-bodied competitors in the majority of situations, and as such, on a purely numerical basis, they are ‘less impressive’. Human nature dictates that we thus find them less interesting and compelling to watch for an extended period of time, a problem compounded by the sheer number of different classifications, leading to a huge number of medals and competitions and thus a confusing and some might say unfocused set of events that becomes impossible to keep track of (there are, for instance, six different classes of cerebral palsy 100m sprinting, giving the athletes concerned 6 times less attention, 6 times less focus and interest and making their medals seem only a sixth as valuable).  All this means that the amount of funding and (especially) media coverage offered to the Paralympics is significantly less than the Olympic equivalents, despite a great advance in recent years, and that they are simply not taken quite as seriously as Usain Bolt & Co.

All of which begs the obvious question: are Olympians really better than their disabled counterparts, or do the mental battles, financial struggles, and management of trying to hold down a paying job before we even consider the crippling physical impairment enough to render Paralympic Athletes even more impressive?

This question ultimately boils down to a question of which is more impressive- being the best in the world, or being merely far, far better than the rest of us mere mortals despite having to overcome. To consider an example, the world record for 100m sprinting in the most severe class of blindness is 11.03 seconds, less than a second and a half slower than Usain Bolt’s fastest ever time and far faster than anyone I happen to know- and this is done whilst entirely unable to see where you are going.

OK, you might say, but blindness doesn’t actually affect physical capability, so what about something that does. Consider the shot put, which involves throwing a large metal ball weighing 16lb (7.26kg) as far as possible with a rigidly monitored technique. 7kg is a surprisingly ungainly mass at the best of times, but when compacted into a small, dense ball thrown in one hand it becomes even harder to handle. I have thrown a shot in school, much lighter than an Olympic one, and got it about 2 metres. Karmel Kardjena is quadriplegic, as in all limbs severely damaged to the point of muscles not working properly, and can throw it 11.

These are just examples I can find on Wikipedia that make for a good comparison- I’m sure a dedicated student of the Paralympics could quote dozens more. Perhaps the most famous Paralympian of all, South African sprinter Oscar Pistorius (aka Bladerunner) won a silver medal in the 2011 World Championships INSERT BIT ABOUT 2012 WHEN HE’S DONE IT (competitions he entered despite a 2008 ruling, which he later successfully appealed, that the carbon fibre replacements for his amputated forelegs were giving him an unfair advantage). He is competing amongst the very best in the world, regardless of the fact that he has no calves or feet, and he is representative of the sheer quality that is surely present among Paralympians.

However, in order to judge our argument effectively, we must still consider how impressive our able bodied athletes are. I have already dedicated an entire post to just how superhuman these people are, but it’s worth taking another look around at the plethora of talent on display over the last fortnight to truly comprehend that. To take a parallel with Kardjena, let us consider the equivalent men’s shot put record. We must, of course, bear in mind that able bodied athletes are capable of not only taking a hopping run-up but also twisting the full trunk of their body, but even so, their achievements are staggering- the world record is over 23 metres (interestingly enough still shorter than the shortest discus throw in Olympic history, at 25).

So then, which is better? Well, to be honest it really comes down to a matter of opinion. Some may believe that the sheer quality of Olympic athletes cannot be made up for by the disabilities of Paralympians, whilst others will say that they more than cover for it and that the Paralympics is the home of real sporting greats. But, in many ways, this argument is entirely irrelevant, if only because we could argue until the end of time and not reach an answer. The real fact to acknowledge is simply that these Paralympians are clearly not here ‘just to take part’- they are serious athletes going in serious competition and capable of seriously amazing things. Whether Oscar Pistorius is better or worse than Usain Bolt matters not so long as we are all agreed that both of them are so great, so beyond what any of the rest of us can do, that they deserve every ounce of admiration we can muster. As the father of the modern Olympics, Pierre de Coubertin, famously said: “The important thing in life is not the victory but the contest; the essential thing is not to have won but to have fought well”

And sorry for the rather lame cop-out