She has multiple sclerosis and runs. Watch what happens around the 49 second mark of the video to see what happens to her legs at the end of a race. It is worth watching until the end to see how it pans out.
For more: Running with Multiple Sclerosis (PodiaPaedia) and Running and multiple sclerosis (Podiatry Arena)
Famous Words of Inspiration...
"The direction in which education starts a man will determine his future life."