Most of your skin type is due to genetics, but skin (and general body structure) is also effected by exposure and use. The skin on your face is mostly affected by weathering and sun, but your palms and feet are a good example of what can happen with lots of use and contact, they can develop fairly obvious callouses and thick areas. Even bone structure can be solidified by lots of use and pounding.
It all depends on what you do with yourself. Increased blood flow throughout the body (due to lots of exercise) can also effect skin tone (and a lot of other things). We are all, partly a reflection of our genetics and partly a reflection of our habits.