I have always been a fan of using isolation in an image to create a strong photograph. Typically it can be done rather easily as the dynamic range of a camera is much lower than the dynamic range of our eyes.
What does this mean? While essentially that our eyes can see a wider variation between highlights and low-lights then our camera can. We can use this “limitation” of our camera to help isolate our subject either into the darkness or into a purposely over exposed brightness.
It is rare to see a mountain bike photo that has been isolated. Typically when mountain biking you are under a canopy of tree tops (as was this situation) and the dynamic range of light is compressed all into one that your camera can see. This is where I bring in the flashes. I purposely under exposed the entire shot. This makes it seem almost as if it was night. It was not although it was later in the evening. There was still plenty of natural light then.
After under exposing the shot I used flashes on each side of the trail to properly expose the cyclist. This creating the isolation of the cycling in the darkness.
Meta Data//Exposure 1/250 @ f/5.0 ISO 200//42mm