But to understand how these functions are executed, everything gets more complex.
For each muscle, there is about 300 to 400 motor neurons that innovate it to move. Each of those motor neurons receive about 25 inputs from the brain. In a recent study, Dr Jessell found that there are as many as 200 classes of nerve cells that influence movement.
And understanding every single one of these cells and neurons counts is crucial to understanding why one body is different to another.
‘You can imagine the complexity of trying to understand the logic of why Simone Biles moves so well is daunting.
‘For a lot of people, you only really appreciate movement when you lose it. For example if you were to suffer an accident like Christopher Reeve, or for people who have ALS. Then you watch someone like Simone Biles and really wonder how and why the nervous system works.’
