I really believe it has a lot to do with the sunshine(vitamin D) the fresh air (stimulates all the surface nerve endings) and to not be surrounded by things to buy, chores to do. The simplicity of slapping a PB&J together, throwing it in a backpack and taking a short or long hike makes everything better. We are getting ready for our summer camping trip(hubby and I go in the fall as a lovers retreat). We will be up in the Delaware water gap. Lots of waterfalls, trails and some rafting. We have a good site picked out thats more off the loop of the main drag which is more private. A 1/4 to the bathrooms is a bit long but we decided that peace and privacy were more worth it. Also, if you are active camping or being outdoors, like hiking you are exercising which is good for you as well.