There is no secret.
The secret is in the head not in the legs; you won’t see anything.
It’s the determination; the passion; the interest; the commitment; the focus; the dream.
These aren’t secrets. These are true of any successful person in life, of any person who can rise above the ordinary.
FAST – Focus, Alignment, Stability, Timing (Tempo off ground)
Easy running: no physical stress; “strain on the face.”