+1. Both versions are great. I guess if I were to pick one I'd chose the second version with one runner (maybe). Tough call.
For me, it's not even close.
The body position of the runner in back is weak, tired; it detracts from the image in many ways.
First, by creating too much busy-ness in the serene, cold environment. Second, by looking tired in its stance.
In contrast, the first runner is colorful and has an active, vibrant posture.
By removing the second runner, the tired posture of the trailing runner is discarded, which is a good thing by itself.
In doing so, the lone figure of the one runner augments the feeling of environmental vastness, stillness in contrast to his efforts.
IMO, the removal of the rear runner was a great idea and strengthened and already interesting composition tenfold.
Jack
