If our bodies know best, why are they easily injured when we do something so seemingly natural as running? On the one hand, running seems very easy, but that is only because our bodies are so very good at it. The most powerful supercomputer on the planet cannot administer the enormous number of computations it takes to run, untethered, on two legs. Wherever our running intelligence is, running is not all conscious to us and is so complicated that only the T-1000 Terminators of our imagination are able to do it. Because our running knowledge is buried so deeply within muscle fibres, cells and our DNA, we have to accept that we cannot fully explain its complexities. That doesn't mean our bodies don't know how to do it. We may feel our way towards understanding the alchemy of running by learning how to use our senses, getting them firing, and seeing what they are capable of, and accepting that our bodies know more about running than we ever will.