I have been training Brazilian Jiu-Jitsu for over 3 years and actively compete as a blue belt. I train to incrementally rid fear from life by facing it in its physical and primal form. Although there will always be fear in life, it should not undermine purpose.
The mental clarity and feelings of happiness that follow a hard training session are nature's gift for letting the human body free to move in the way it was intended. In an artistic sense, we can view ourselves as the canvas in this art form, and the stress of physical combat as the paintbrush.
The famous Michelangelo believed the sculptor was a tool of God, not creating but simply revealing the powerful figures already contained in the marble. Michelangelo's task was only to chip away the excess, to reveal. The same can be said to the potential of our own bodies as athletes.