As a photographer, I am REALLY fascinated by this. I love juxtaposition in art, fashion, and pretty much anything.
As for the lighting, it is exactly the same in both the "before" and "after" images-- all with powerful studio lights (you could set this up in daylight and the sun won't interfere with your shot if you have the right gear and know what you're doing).
The "before" images seem harsher probably due to the sweat creating more noticeable specular highlights, and the joggers are also coming from a very focused activity and have just met a stranger with a camera-- all these things will naturally make the "before" shots seem closed off, guarded, and intense. Once the joggers are back in the studio, cleaned up, they feel more confident, and the photographer is no longer a complete stranger. They're going to be more relaxed and look more open in the second image.
