Notes

I like the freedom that running offers me. While running, I am not accountable to anyone. It’s my time and I value the solitude and the invisible barriers that I have.
I don’t consider myself a runner because I think that term classifies die hard athletes whose lives revolve around the sport.
The energetic ones were zipping down the road, slicing through the air like they had robbers at their heels.
I can remove myself as far away from current matters as possible by ruling frustrations and anxieties out of my system, at least for the time being. Other times, I do not think, I immerse myself in the nature, wind, running gives me a sense of control.
Running is about speed and endurance. Some animals are natural sprinters, other are more long-distance runners.
Given that running fast or for long periods of time can make the difference between getting a meal or going hungry (or indeed being a meal or staying alive) it is not surprising that there have evolved several useful adaptations in the animal kingdom to hone the art of running.
As anyone who has tried to get close to one in the wild can attest, lizards are quick sprinters, yet they cannot run fast for long for the very good reason that they are physically unable to breathe while running (the body flexes so frequently that there is not enough time for either lung to fully inflate). Without the oxygen needed to refuel their cells, a lizard’s muscles will become exhausted after about a minute or two.

Certain reptiles, crocodiles, have evolved way around the problem of running and breathing at the same time. The true masters of running, though, are the mammals, some of which have evolved in such a way that their entire bodies are adapted for speed and endurance. Mammals have their limbs below their body and a flexible spine, both of which allow for movements that efficiently transfer power from the muscles into forward momentum.

Walk in a sprawling, swaying motion like a lizards, each step resulting in the body twisting left and right.

Cheetah is the best known sprinter. The power to get to the high speeds comes from the muscles, which are packed with fast-twitch fibres that contract quickly and powerfully and can continue to work even in anaerobic conditions (when the muscles are starved of oxygen). Fast-twitch fibres are balanced with slow-twitch fibres, which are used for endurance running and walking. Cheetahs have a 20% higher concentration of fast-twitch fibres than other fast-running mammals such as the horse or greyhound. For the muscles to be used efficiently, the cheetah has a highly adapted skeleton for running. It is designed to allow a huge stride length, some 7 metres at full speed, and it can complete four strides each second. This is stride is possible only from having such a flexible spine, which not only gives the cheetah a long stride length but also gives extra energy to the running animal. When it bends, it stores energy, which is released when the spine springs out straight again. Further range in movement is permitted because of the way the hips are allowed to pivot and because the shoulders are not attached to the collarbone. In addition, the cheetah has enlarged nostrils, sinuses, lungs, and heart to get oxygen into the blood and to the muscles. It also has a huge respirator capacity and is able to take 150 breaths per minute – double what humans are capable of. The animal is also extremely light (35 kg) that this could potentially cause problems with stability when at it is running at top speed and needing to change direction. The best long-distance runner is human. The skin covered in sweat glands prevents overheating, but humans also have a wealth of other adaptations that make them excellent endurance athletes. Long tendons in our legs store energy with each step and release it when our feet spring forward. We are well-balanced too. Swinging arms, a twisting torso, and strong muscles that keep our head still all allow for efficient distance running. All this combined with a highly efficient cooling system means that we can keep running for mile after mile.