How well are we equipped to run? - 3. Other equipment April 20 2016, 0 Comments
So far, we have looked at the legs and feet, so it is probably time to look at the other anatomical aids we have for long-distance running.
Let's start with breathing. If you watch fast-running four legged animals you can see that at the two extremes of their stride they either stretch or crunch, and this can have a dramatic effect on their breathing.
If you are at full stretch, it is much easier to breathe in than out, and if you are crunched up, exhaling is the most comfortable option. So breathing is linked to pace, and that is an intrinsic limitation. Cheetahs are astonishingly fast, but they run out of puff pretty quickly. Being bipedal enables us to disconnect our breathing from our pace. We may choose to breathe in time with our stride, but if push comes to shove we can double or triple our respiration rate without affecting our running, a handy trick if you want to maintain a pace for a long distance.
Another thing that you will notice with most animals is that they pant to cool themselves down, and this also has limitations. Running generates heat, and if you are pursued by an animal until you cannot cool down as fast or faster than you heat up, eventually you simply have to stop. If the animal pursuing you happens to be homo sapiens, he has the major advantage of being able to sweat across the full breadth of his skin, and the evaporation of the sweat cools him and gives him many more miles of distance before he overheats. The evidence suggests that we were on a high-protein diet (meat) long before we invented tools and weapons, and that running after animals until they simply lay down from exhaustion was how we caught our food.
Finally, in our necks we have a nuchal ligament, something that his found almost exclusively in running animals. It serves to support the weight of the head without muscular effort, and to hold the head still while running.
So the anatomical evidence is looking pretty strong that we were built to run. In the next instalment we shall look at what we can do that supports the man-as-long-distance-runner theory. In the meantime, you might like to have a look at some of ZEMgear shoes that protect your feet but still allow you to run as nature intended.
Why are the soles of our feet so sensitive? July 11 2014, 0 Comments
It seems counter-intuitive that the surfaces on which we rest the most weight are some of the most sensitive in the body - think of the last time someone tickled your feet, or you tried to walk across gravel in your bare feet...
To some extent, this is the result of wearing shoes. People who habitually go barefoot all the time develop some fatty padding under the skin, and the skin of the soles becomes thicker, forming a protective cushion. Even factoring this in, the concentration of nerve endings in the soles of the feet is extremely high, and the nerve fibres leading from the to the brain are very fast - so why?
As pointed out by Dr Mick Wilkinson of Northumbria University, if you normally run in shoes, and then take them off and run on a hard surface, you will find that your gait changes naturally. The feeling of a heel-plant, which is perfectly OK with a couple of centimetres of padding on your sole, no longer feels right, so you change your gait to soften the impact. You will probably move more to a forefoot landing, or at least a much flatter one - much the same as the way that children run. It has been hypothesised that this is why the feet are so sensitive - that this acute feedback causes us to adjust our gait to fit whatever the conditions may be, and to lessen the impact on our soles and through our joints. It is further argued that this results in a more economical style of running.
And in order for this to work well, we need sensitive soles and fast message transfer through the nerves to adjust our running as quickly as possible.